G0766 opinions, considering a new lathe.

[cody michael]

I have the nicer Harbor freight lathe and I have really enjoyed it, but I like making big bowls and it is to fast and very under powered, i saw a G1495 at a garage sale the other day that I considered, but I think it has the same flaws as my Harbor freight lathe, I would really like to get a g0766 it seems like a great value, and has a capacity for pretty huge bowls. I know a lot of people on here bought one and wanted to hear if you regretted it or if it was what you were looking for?

[Roger Chandler]

My G0766 is running great, and I am very glad I got it. A smooth, quiet and powerful lathe with basically the same features as the Powermatic 3520b, with the exception of the spindle lock button........the G0766 uses an index pin for the spindle lock feature [which I personally prefer]

3 hp- 3 phase motor, premium Delta Electronics M series inverter, 42" between centers, and stable. Best value on the market for a large lathe.

[Randy Red Bemont]

The 0766 lathe is great. Sounds like it will do everything on your want to do list and more. If you were closer I'd have you come over and try one. Good luck with what ever lathe you upgrade to.

Red

[cody michael]

Does anyone know where I can get a Grizzly 10% coupon this fall?

[Randy Red Bemont]

One of the woodworking magazines (either WOOD or WWJ I don't remember which) usually has a coupon in the fall and the other one in the spring.

Red

[mike pockoski]

321437
Here's my G0766 from last night... It's performing great and making plenty of shavings! Only complaints are the ones already discussed by everyone...shipping and banjo. I'm imagine by now the shipping is in better shape, and the banjo issue is getting rectified... For a turner like me on a Harbor Freight budget, it's been a dream machine! I've turned some fairly big wood on it...20 inch bowls 8-10 inches deep. No problem at all spinning it fast and throwing shavings all other the shop.

Squint your eyes and pull the trigger on it, you'll be happy you did!

[John Keeton]

Mike, you need to make sure your family knows when you are at the lathe. Otherwise, you could become MIA in shavings!:D

i have not seen the 0766 in person, but I did take a good look today at the new Laguna 1836 while at Woodcraft. Laguna has somewhat of a checkered past on lathes, but from looks alone (I did not turn on it), it sure seems like they listened to folks. It was clean and with only a couple of minor things, very impressive. Nice, wide stance in the legs and some excellent design features and options. It would be helpful, of course, to hear testimonies from experienced turners before considering that option.

[Russell Neyman]

Gotta finally get up the nerve to say this, but it sure seems to me somebody in the Grizzly Marketing Department has figured out how to get the audience to plug this particular lathe. I mean, the specific make and model number keeps popping up in the SMC subject lines, right down to the designation of an zero instead of an "O." The questions and comments sure sound like setup, too. Might just be my suspicious nature, but it has occurred to me that all these mentions might be a PR ploy spurred on by a sales rep. Don't get me wrong; I own several Grizzly machines (none of them lathes) but I've always thought of this brand as rather run-on-the-mill quality.

Having said that, I'll chime in on John's comment about the new Laguna 18-36 and give it a plug. Two of my fellow turners purchased them in the last two weeks, and it really looks like an extremely well-designed machine, and a great buy for the $2350 price tag.

Time will tell for both of these. Stay tuned.

[Brian Kent]

Russell, I would say, "Absolutely not" to your fears. These guys do not fake reviews and they do not hesitate to encourage each other to spend tons of cash and credit. Grizzly lathes were gaining acceptability over time with their last two bigger lathes. When the G0766 came out in the catalogue at the end of last year, they had significantly beefed up the size and power, with a significant price drop. A lot of people saw their opportunity to buy a larger, more affordable lathe. I have been watching the details of reviews closely and plan on buying mine in the Spring or Summer.

[Roger Chandler]

Yeah,...what Brian said. I have zero affiliation with Grizzly, and what you are seeing Russell , is the fact that a good number of people have now had time to vet their G0766, and have found it to be a fine performing, large lathe. While they are updating the banjo [commendations for stepping up!] and they had some loose conditions in a few of the crates, they are addressing those with the factory from what Shiraz Balolia told us.

Mike's pic above says it well.......this is a very capable lathe!

[Cary Falk]

Does anyone know where I can get a Grizzly 10% coupon this fall?

There used to be one in Wood in the fall. I have not seen it yet. I already had it by now last year. I also got one last year in an e-mail last year around this time. Woodworker's Journal usually shows up in the spring.

[Mike Goetzke]

321437
Here's my G0766 from last night... It's performing great and making plenty of shavings! Only complaints are the ones already discussed by everyone...shipping and banjo. I'm imagine by now the shipping is in better shape, and the banjo issue is getting rectified... For a turner like me on a Harbor Freight budget, it's been a dream machine! I've turned some fairly big wood on it...20 inch bowls 8-10 inches deep. No problem at all spinning it fast and throwing shavings all other the shop.

Squint your eyes and pull the trigger on it, you'll be happy you did!


WOW - what did you turn! (you better get a bigger fire extinguisher)

Mike

[cody michael]

Thanks guys, I'm really hoping I can scrape up enough pennies... I have also found a delta dl 40 that's up for auction, if the price is right i may jump on that, it's currently 200$ it ends Thursday so I'll see what happens there but if that falls through the g0766 is really the only new lathe I'm considering, it's definitely over my budget but seems like a good value. I haven't seen anything else that is anywhere close to my budget for comparable size, speed control etc.

[hu lowery]

About packing, my first 766, the packing was horrible! No crate damage at all but they could have just thrown everything in the crate loose and not made much difference. Sent that puppy back after finding a few flaws too many.

The next lathe had heavy crate damage, nothing to do with Grizzly. Obviously far better packed, a far better packing protocol just for starters. I have been a bit cursed with the 766, this one had a "bearing" rattle. When I took apart the headstock I found the bearing rattle was actually a loose spacer. Anyone interested can learn about that in the Grizzly group area.

I had already bought some hopefully upgrade Japanese bearings at the same time I had Grizzly send me a new set. I put the Japanese bearings in as hopefully an upgrade while I have things apart.

My lathe isn't bolted down so I built a tray to hold seventeen or eighteen half-pads at 35 pounds per. Haven't got it fully loaded yet but I spun up the lathe yesterday to see what I had with just the faceplate on it. The belt was on the low speed pulleys so I just spun it up to 1220 RPM but it was almost ridiculously quiet at that speed with the motor at full RPM of course. Impossible to see the machine is running looking at the bed. Laying a finger on the bed there may be the slightest vibration or it might be imagination, it is that little if any.

I roughed a fifty to seventy-five pound chunk of out of balance oak before adding the ballast. Was working OK although RPM was limited to three to four hundred due to rock and roll. I was turning between centers and wasn't particularly surprised when I spun a spindle drive center. Waiting on stuff to get here and I couldn't put my chuck and Texas spur on.

Had a lot of headache with the Grizzly. I know the folks at tech support pretty well and they are all pretty nice! Judging by my second lathe I would say the packing issue is largely taken care of. I confirmed before buying the second one that all 766 owners will receive the new banjo when it is available.

Considering how stout this machine is, the quality of build, and my needs I don't think I will ever need another lathe. Good thing, if I get the itch I don't see any reason I can't use this lathe to turn stuff to pay for either a homemade monster or an American Beauty. Have to admit that I would like to have an American made lathe, as much general principles as anything else. I could buy a half-dozen of the 766's for the price of one American Beauty fully dressed like I would like it. That makes the green machine look a lot nicer than if it was close to the same price!

Been busier than a three legged dog scratching fleas between end of summer on the farm and other commitments. Hard to believe how long I have had the new lathe sitting there and haven't really turned anything on it. Most of my toys are in place other than my vacuum chuck which is about 80% complete and my camera system for my hollowing tool which I haven't even started on, got a laser anyway. Hopefully I'll get something turned very soon. A little cooler weather finally came this way and will help encourage that. I am turning in an old galvanized dairy barn with no climate control. A week ago I could have fried eggs and a side of bacon on the lathe ways!

Hu

[david privett]

I would absolutely buy a g0766 again, the minor issues can not diminish the fact of a big lathe at a small price. As this would not be the first thing I have bought new that I did not have to fool with some. Did some outside turning the other day 15 x 8 red oak unbalanced no vibration issues.

[mike pockoski]

scored a restaurant order of 30 big maple salad bowls! I plan on using the money to buy a coring system so i don't have so many shavings!

[Izzy Camire]

I have been reading this thread with great interest as I have been going back and forth between getting the G0766 and the Laguna 18-36. The Laguna is on an introductory sale at the local Woodcraft for $2249. Have to make a decsion soon as the sale ends next week. Finding the 10% off coupon for Grizzly would surely help.

Thanks to everyone for the info provided in this thread.

[John Keeton]

Given the past discussion regarding the "actual" horsepower of the Grizzly, I noticed that the Laguna motor lists 5.3 amps, as I recall, and 2 HP. The Grizzly shows in the specs 4 amps and 3 HP, for whatever that may be worth if anything.

[cody michael]

thanks for your help, but it looks like there will not be a g0766 in my future, I just bought a delta DL 40. For about 700$ at an online auction I will pick it up next thursday, i can wait!

[Roger Chandler]

My former G0698 was 2 hp rated motor, and was D/C and rated 10 amps draw, .........I think the motor efficiency has a lot to do with amp draw at rated horsepower. The G0766 manual says it can draw more than the rated amps under heavy loads ,but at the 3hp stated hp rating, it draws 4 amps.

I can say from personal experience, that it has plenty of torque and power!

[Thom Sturgill]

I finally got the chance Tuesday to turn on our club's machine. TOO TALL!. The bed height is the same as my jet, putting the spindle height 3 1/2" higher. I stand on 1 1/2" of mat when turning at thee jet, so the spindle was 5" higher than I'm used to.

[John Keeton]

I finally got the chance Tuesday to turn on our club's machine. TOO TALL!. The bed height is the same as my jet, putting the spindle height 3 1/2" higher. I stand on 1 1/2" of mat when turning at thee jet, so the spindle was 5" higher than I'm used to.This is one more example of why I do not feel the Grizzly has been engineered and designed with input from turners. The center height on the 0766 is right at 48". The center height on the Laguna is 41.5"- much closer to what most folks would find comfortable. Again, I have not used either lathe, but the design and engineering of the Laguna is exceptional and obviously done with input from turners.

For comparison, the PM is 44" to center.

Only time will tell on either lathe.

[J.D.Redwine]

Thanks for the information. For me it is good to hear the 0766 is 'too tall'. My Nova 1624 is on 5" pads. Looking forward to ordering a
0766 at the end of the month.

[Robert Henrickson]

The center height on the 0766 is right at 48". The center height on the Laguna is 41.5"- much closer to what most folks would find comfortable.

For comparison, the PM is 44" to center.


I hadn't realized the Grizzly center was at that height. The Jet 1642 center is at a height comparable to the PM. I saw the Laguna when John did -- the center struck me as being a bit low. I've turned on a 1642 for perhaps 8 years, but recently I have done a two-day demo and taught a class at Woodcraft on a 1642 whose center was more than inch higher than mine -- it felt like it was a much greater difference. I got used to it after bit, but I hadn't realized what an effect differing heights can have, at least initially.

[John Keeton]

The user's height, of course, makes a difference as well as that person's style of turning. At 5' 7", the Grizzly would be much too high for me. My Jet, at around 44.5" is a bit high for me, at times. I would note the Laguna has a 3" riser blocks optional accessory.

[Roger Chandler]

This is one more example of why I do not feel the Grizzly has been engineered and designed with input from turners. The center height on the 0766 is right at 48". The center height on the Laguna is 41.5"- much closer to what most folks would find comfortable. Again, I have not used either lathe, but the design and engineering of the Laguna is exceptional and obviously done with input from turners.

For comparison, the PM is 44" to center.

Only time will tell on either lathe.

While it is obvious that Grizzly did use existing parts design to configure the G0766, by using the same bed and leg castings as was on the G0733, and it was not a new model built from the ground up, which when adding the additional swing to make it 22 inches, the overall bargain with upgraded features which include horsepower upgrade and premium Delta Electronics inverter, as well as the beefier tailstock assembly, make the G0766 a real contender on the market for a large lathe.

The spindle height is probably a little high for a short person. I am 5' 11" tall and I do fine with it. I did put down a 3/4" anti-fatigue mat between the lathe legs for my comfort level standing for long periods of time [basically a rubber horse stall mat from Central Tractor] The larger headstock made the height a little higher, so ideally, they should have compensated for that with 2" shorter leg castings.

Performance wise, the G0766 rivals any PM 3520b I have ever turned on, which has been 9 different units to this point, with some having been turned on multiple times. I like the 3520b.......great lathe. The G0766 performs quietly, smoothly and is powerful with plenty of torque. It has more power than any Jet 1642 I have turned on [several of those, including 2 hp versions]

For a lot of turners who are not bothered by the height, or those willing to put a platform to stand on, they will be getting a lot of lathe for a superb price, which is probably why Grizzly went the route they did using existing part designs, as that would likely allow them to make this unit available at a bargain price, not having to re-engineer the design. For most people who do not have height concerns, they will find this G0766 to be a great performing lathe.

I want to say this........I have absolutely no affiliation with Grizzly, and have no reason to want anyone to purchase any product from them whatsoever. I just think that misperceptions can develop in the minds of people, and that they should hear from actual owners of the unit.

I much appreciate the perspectives that John and Thom have given to this thread. John called it right when he mentioned it not being engineered as a "total package" with ergonomics as a top priority.

That being said, the G0766 will be just fine for someone not "vertically challenged." Someone of average height can do just fine and dandy with it, but there may be some turners who like their lathe bed to be lower, or the spindle height to be lower as that is what they have gotten used to turning on. I am certainly not the only owner of the G0766 to come on this forum to attest to the performance of the G0766. Others can feel free to chime in if they wish, but this lathe will fill a niche and be a recognized contender in the large lathe category, IMHO!

[daryl moses]

My G0733 was a bit too tall for me. Just about any full size lathe would be as well as I am only 5'5" tall.
Good thing about the Grizzly though is they furnish you with enough lumber to build a platform so you can adjust the height to your preference.;)
A pretty good trade off for a couple of thousand $$$$ savings.

[John Keeton]

Roger, I really don't mean for this to be a continuing saga, but my position all along has been that I believe a woodturner forms a very close connection to his or her lathe - spending hours on end in front of it. That is normally different from the other stationary tools in one's shop. It is important that one's posture be correct, and that the user remains comfortable for those turning sessions - particularly for those of us in the "senior" category.

Obviously, others may differ, but a lathe should be designed by folks that are familiar with turning - intimately. Putting together a lathe from a mix of parts to produce a machine that runs smooth, and has a lot of power (attributes noted by users of the 0766) doesn't mean that the lathe was ergonomically designed. There is a reason that the veteran turners use the lathes they use - PM, Robust, etc.

The Laguna may be a piece of junk - I don't know as I have not used one and I do believe it takes more than a few hours on a lathe to know if it is a quality machine in all respects. What I am saying, however, is that the design of the Laguna leaves one with the impression that there was significant input from folks that knew how a lathe was to be used. I said the same about the PM, and obviously the Robust lathes are exemplary examples of this. And, there are others. On the other hand, it seems obvious to me that the Grizzly lathes differ in that regard. Otherwise, they would not assemble a conglomeration of parts from other machines to achieve the end product just to meet an attractive pricepoint.

All that said, I am sure the 0766 owners are happy with their purchase and it suits their needs. In fact, each of the two previous lathes I have owned did that - met my needs at the time as I knew them to be. At some point, however, one decides this turning thing has become an integral part of their life, and when that time comes, if finances support it, it would seem prudent to buy a lathe that is truly designed for turners.

At a price of between $2300 - 2500, the Laguna would seem to be serious competition for the the Jet 1642, but time will tell. At this point, the Jet is fine for me, and I don't expect to upgrade anytime soon. But, if I do, it will not be the Grizzly. The cost difference for a well designed lathe seems to be money well spent - for me. Perhaps not for everyone.

I am glad you are happy with your lathe, and since you have owned a couple of Grizzly lathes, they seem to work well for you. But, in fairness to those other folks that might be considering moving up, or perhaps even buying their first lathe, I believe it is important to consider the design features of the lathe far more than the swing or the power. Personally, I have never had the need to turn anything beyond what the Jet will handle - either in swing or power.

[Roger Chandler]

Well said, John.......no disagreement here on my end! Ideally, as you say, the design should be well thought out. I believe most turners will find that the G0766 will fit them.......a few may not, or may have different preferences as their relationship with their lathe becomes as you say, more intimate and individualized.

I think the Laguna model you reference will likely be a fine unit. I hope that Laguna's service will match up to it, as in the past there have been many complaints with their CS.

The fairness of informing others who might be considering moving up or buying their first lathe is of importance to me as well. As you mention, neither you or myself intend for this to become a saga of going back and forth, tit for tat. I have too much respect for you for that sort of thing, and as I mentioned in the previous post, I have no interest whatsoever in wanting anyone to purchase any lathe from any company....Grizzly included!

In time, I may decide to step up to something like a Robust American Beauty........could have done it this time, but had other fish to fry with those funds. I feel like my purchase of the G0766 was an intelligent move, and got a value and performance that was surprisingly good, notwithstanding the banjo issue which is getting rectified. One poster on the Grizzly Green Monster Group told us that the new banjos ship from China on Sept 18th. which is today.......:)

[Jeramie Johnson]

I would prefer to raise myself if needed, than raise the machine. I don't wobble as much as the lathe will at 2K rpms.

I stand in at 5'8" and actually like the taller lathe....less bending over, work closer to the eyes. My Delta was way too low, raising it by blocks brought more wobble with unbalanced logs. I was surprised when I read a month ago or so someone claiming to be near 6 ft and the Grizz was too tall. (I grabbed a tape measure that night and took my measurement again....thought maybe I grew a foot or so. Alas...no, wife is still taller)

[Dale Miner]

The full load amperage draw on 220 volt for a 3hp 3 phase motor is about 9.5 amps per leg (3 legs). If the 3 phase motor is being supplied with power from an inverter that has single phase input (2 legs) the supplied 220 volt single phase amperage needs to be at least 1.5 times the 9.5 amp output.

Something doesn't seem to jive if there is a listing for a 3 hp motor at 220 volt that draws 4 amps.

I have not seen a 0766 to examine the nameplates, but doubt seriously if the motor only draws 4 amps. A 4 amp full load draw would be just a tad over 1 hp output, and would be woefully underpowered for a 22" swing machine.

[Joe Kaufman]

Since you mentioned that you like to make big bowls, consider the spindle bearings. According to the G0766 parts list the spindle bearings are 6206 series one front and one rear. The PM 3520b has a pair of 6207 series on the front and one 6206 on the rear. The 6207 series are larger than the 6206 and higher in load rating. The spindle supported distance between the front and rear bearings is about 50% greater on the PM also a plus factor.

Recently, I replace the spindle bearings on my PM 3520b after about 15 months of use, due to a bearing noise. PM sent 3 bearings for warranty replacement. I took one look at the bearings (China) and purchased and installed higher quality bearings. The original bearings were made in Taiwan and had no exterior quality issues. I would not hesitate to install the original Taiwan manufactured bearings if they were furnished.

This is not intended to try to list the merits of one manufacturer or the other, just something to consider.

[Roger Chandler]

The full load amperage draw on 220 volt for a 3hp 3 phase motor is about 9.5 amps per leg (3 legs). If the 3 phase motor is being supplied with power from an inverter that has single phase input (2 legs) the supplied 220 volt single phase amperage needs to be at least 1.5 times the 9.5 amp output.

Something doesn't seem to jive if there is a listing for a 3 hp motor at 220 volt that draws 4 amps.

I have not seen a 0766 to examine the nameplates, but doubt seriously if the motor only draws 4 amps. A 4 amp full load draw would be just a tad over 1 hp output, and would be woefully underpowered for a 22" swing machine.

The motor is 2200 watts which equates to 3 hp, input, but loses some with the cycling of the inverter on output, which is the same with other makes as well. Not sure how they come up with the amp draw stats, unless the motor efficiency accounts for the lesser amp draw, or the "M" series inverter requires less amp draw? The motor plate does state 3 hp, and 4 amps draw, and the motor is continuous duty rated.

I can say from personal experience, that this lathe does not lack in power......I have turned some big wood on it, and it will sure throw the big shavings all over the shop. Mike's pic of his in the earlier part of this thread sort of shows the same thing.

[carl mesaros]

John I have been turning on the Laguna 2436 for about 4 months now and have been more than satisfied. It does seem they designed it with input from turners.
Mike, you need to make sure your family knows when you are at the lathe. Otherwise, you could become MIA in shavings!:D

i have not seen the 0766 in person, but I did take a good look today at the new Laguna 1836 while at Woodcraft. Laguna has somewhat of a checkered past on lathes, but from looks alone (I did not turn on it), it sure seems like they listened to folks. It was clean and with only a couple of minor things, very impressive. Nice, wide stance in the legs and some excellent design features and options. It would be helpful, of course, to hear testimonies from experienced turners before considering that option.

[John Keeton]

Carl, that is a big chunk of lathe!

[Roger Chandler]

John I have been turning on the Laguna 2436 for about 4 months now and have been more than satisfied. It does seem they designed it with input from turners.
I was impressed with the Revo 2436 when I first saw it online.........I can certainly understand your enthusiasm!

[Dale Miner]

The motor is 2200 watts which equates to 3 hp, input, but loses some with the cycling of the inverter on output, which is the same with other makes as well. Not sure how they come up with the amp draw stats, unless the motor efficiency accounts for the lesser amp draw, or the "M" series inverter requires less amp draw? The motor plate does state 3 hp, and 4 amps draw, and the motor is continuous duty rated.

I can say from personal experience, that this lathe does not lack in power......I have turned some big wood on it, and it will sure throw the big shavings all over the shop. Mike's pic of his in the earlier part of this thread sort of shows the same thing.

Roger,

I have not turned on this model lathe, and take your word on the power available to the turner.

You can't get something for nothing in the power world. 2200 watts is about 2.9+ horsepower with a 100% efficiency.

4 amps x 220 volts = 880 watts = 1.18 hp @ 100% efficiency.

2200 watts ÷ 220 volts = 10 amps

Something doesn't equate.

The inverter can't increase the efficiency from input to output by a factor of 2.5. In fact, inverters decreases the thru put efficiency by some small amount.

I am curious as to what the rest of the motor nameplate info is. Things like volts, full load amps, rpm, service factor, temperature rise, etc.

There is an apparent discrepancy in some of the electrical info for the machine, but the motor nameplate should give the straight and skinny.

I have a shop vac that runs on 110 volts and claims to have 5hp. 5 hp on 110 would need about 35 amps, and that can't happen from a standard wall outlet thru a #16 cord. Obviously the shop vac manufacturer used a different formula for their advertising info.

[David C. Roseman]

I agree with Dale about a discrepancy somewhere. We really ought to drill down on this, as this power issue has come up a number of times. I have the Grizzly G0733 18" x 47" lathe, the "little" brother to the G0766. Its motor is rated by Grizzly as 2 hp, vs. the 3 hp of the G0766, yet the sticker on the motor housing says 5.2 amps. I've never stalled it, even roughing heavy 18" bowl blanks, so it has plenty of torque. The G0733 uses the same highly-rated VFD as the G0766 (Delta VFD-M series).

Dale, how would you go about measuring actual amperage draw on one of these machines with a clamp-on ammeter? Seems like that would be worth doing. Presumably we'd have to pull the NEMA 6-20 receptacle part way out of its electrical box in order to clamp on each conductor, as there is no ready way to access the conductors at the drive or motor and still have the lathe running. I haven't looked into it, so I don't know how the presence of the VFD circuitry affects amp measurement with a basic clamp-on meter.

Another question would be how to bring the motor to full amperage draw for an accurate test? Would we have to have someone turning a big blank, trying to actually stall the motor? Also, at what spindle rpms, since presumably the torque curve varies depending on pulley and speed selection. :confused:

[Roger Chandler]

I agree with Dale about a discrepancy somewhere. We really ought to drill down on this, as this power issue has come up a number of times. I have the Grizzly G0733 18" x 47" lathe, the "little" brother to the G0766. Its motor is rated by Grizzly as 2 hp, vs. the 3 hp of the G0766, yet the sticker on the motor housing says 5.2 amps. I've never stalled it, even roughing heavy 18" bowl blanks, so it has plenty of torque. The G0733 uses the same highly-rated VFD as the G0766 (Delta VFD-M series).

Dale, how would you go about measuring actual amperage draw on one of these machines with a clamp-on ammeter? Seems like that would be worth doing. Presumably we'd have to pull the NEMA 6-20 receptacle part way out of its electrical box in order to clamp on each conductor, as there is no ready way to access the conductors at the drive or motor and still have the lathe running. I haven't looked into it, so I don't know how the presence of the VFD circuitry affects amp measurement with a basic clamp-on meter.

Another question would be how to bring the motor to full amperage draw for an accurate test? Would we have to have someone turning a big blank, trying to actually stall the motor? Also, at what spindle rpms, since presumably the torque curve varies depending on pulley and speed selection. :confused:

I think there must be some formula that is being used by Grizzly that is not standard........not sure why, and it would be interesting to have some measurement like you mentioned David. Noting the oddity on the amp draw/hp rating here, I am wondering if perhaps something about the way the inverter is programmed makes this possible.....although that is over my head as far as my current level of understanding of things in the electrical/electronics world. :confused:

I appreciate Dale, and others like Ralph Lindberg and Bill Boehme who know so much more than I do related to these things........and of course, I sense that you also have greater knowledge as well David!

I do know that this lathe has lots of torque and power......I have not stalled it yet, but have no doubt I could if I tried to. I have stalled more than one PM3520b and also a Robust
American Beauty -3 hp version, so stalling the G0766 is certainly possible with heavy cuts!

[John Keeton]

For whatever difference it may make, the Grizzly uses the M series VFD and the Laguna uses the S series. I know nothing about this subject - just throwing it out there to see if that tells anyone anything.

As an aside, I must be doing something wrong or else a whimp turner. I have never stalled my Jet 1642-2. Nor have I attempted to.

[Dale Miner]

For whatever difference it may make, the Grizzly uses the M series VFD and the Laguna uses the S series. I know nothing about this subject - just throwing it out there to see if that tells anyone anything.

As an aside, I must be doing something wrong or else a whimp turner. I have never stalled my Jet 1642-2. Nor have I attempted to.

John,

Don't feel too bad.

The world needs whimp turners too. :D

Actually, when I had a PM3520, in low gear it was pretty tough to slow it down with anything smaller than about 16". In high gear at rough out speeds it was easier of course.

The 2hp 2436 I have now has less oomph in the mid range belt setting than the PM in low, but in granny gear belt setting is more than I can stall when running above 100 rpm's or so. Of course I'm older now and maybe getting a bit whimpy in my golden years.:(

The real test of power; "Is it enough to make the owner satisfied."

If a prospective buyer has a doubt, a test drive with a larger blank would be prudent.

I'm still curious as to what the rpm, service factor, etc, info on the motor nameplate is.

[Dale Miner]

I agree with Dale about a discrepancy somewhere. We really ought to drill down on this, as this power issue has come up a number of times. I have the Grizzly G0733 18" x 47" lathe, the "little" brother to the G0766. Its motor is rated by Grizzly as 2 hp, vs. the 3 hp of the G0766, yet the sticker on the motor housing says 5.2 amps. I've never stalled it, even roughing heavy 18" bowl blanks, so it has plenty of torque. The G0733 uses the same highly-rated VFD as the G0766 (Delta VFD-M series).

Dale, how would you go about measuring actual amperage draw on one of these machines with a clamp-on ammeter? Seems like that would be worth doing. Presumably we'd have to pull the NEMA 6-20 receptacle part way out of its electrical box in order to clamp on each conductor, as there is no ready way to access the conductors at the drive or motor and still have the lathe running. I haven't looked into it, so I don't know how the presence of the VFD circuitry affects amp measurement with a basic clamp-on meter.

Another question would be how to bring the motor to full amperage draw for an accurate test? Would we have to have someone turning a big blank, trying to actually stall the motor? Also, at what spindle rpms, since presumably the torque curve varies depending on pulley and speed selection. :confused:
David,


If the motor namplate gives the info, I would guess that is sufficient. If not, then measuring would be a involved process. To get full load amperage draw the rated full load rpm of the motor would need to be known. Typically a motor will run very near synchronous at no load, and wil slow to nameplate rpm's at full load.


Absent nameplate info, right or wrong, my method would be to measure the amperage on the single phase input because it is easier to access, and calculate the wattage input. To get full load, the frequency from the inverter would need to be adjusted to 60 cycles, no load speed measured, and then an adjustable brake method of some sort fashioned to load the motor until the full load 60 cycle rpm was reached. The amperage draw at that point x the input voltage would yield a value about 15% higher than the actual motor output.


I assume the motor is a nominal 1750 rpm full load 60 cycle motor. If so the synchronous speed would be 1800 for the motor, and the no load speed very near to 1800 rpm.


Horsepower is a factor of speed times torque. The torque a motor can deliver is for the most part a function of the rotor diameter and length. The slower the speed of the motor, the larger the rotor (and stator) need to be for the same horsepower output. With most current inverter powered wood lathes, the motors are oversped above nameplate rpm's and the advertised hp is with motor at the full load 60 cy rating. When the motors are running below 60 cycle rpm's, the horsepower is less, and when above 60 cycle rpm's the horsepower can be above namplate. Some inverters are capable of boosting motor torque at slower speeds to help compensate for a loss of hp at lower rpm's, but there is a limit to the boost.

I used to occasionally do some vibration analysis on rebuilt motors when still in the motor shop. To test a rebuilt motor, they (shop personnel) would couple the motor to a dynomometer and measure the amperage and torque curve as full load was reached. Methinks that is way to much trouble for what the answer is worth.

[Roger Chandler]

John,

Don't feel too bad.

The world needs whimp turners too. :D

Actually, when I had a PM3520, in low gear it was pretty tough to slow it down with anything smaller than about 16". In high gear at rough out speeds it was easier of course.

The 2hp 2436 I have now has less oomph in the mid range belt setting than the PM in low, but in granny gear belt setting is more than I can stall when running above 100 rpm's or so. Of course I'm older now and maybe getting a bit whimpy in my golden years.:(

The real test of power; "Is it enough to make the owner satisfied."

If a prospective buyer has a doubt, a test drive with a larger blank would be prudent.

I'm still curious as to what the rpm, service factor, etc, info on the motor nameplate is.

Dale..........this is the motor label. Not sure it gives you all the info you want, but this is what they put on the motor.

321783

[David C. Roseman]

For whatever difference it may make, the Grizzly uses the M series VFD and the Laguna uses the S series. I know nothing about this subject - just throwing it out there to see if that tells anyone anything.

As an aside, I must be doing something wrong or else a whimp turner. I have never stalled my Jet 1642-2. Nor have I attempted to.

John, I've seen your work, and if you're a wimp, we're all in trouble! :eek:

On the issue of the Delta Electronics variable frequency drives, for Creekers who are interested, I looked into this a bit when I bought my G0733 three years ago, and also discussed it briefly a couple of years ago with a Delta Electronics tech at their Raleigh office when I was adding a braking resistor. Delta's product line for AC motor drives can be found here: http://www.deltaww.com/Products/CategoryListT1.aspx?CID=060101&PID=ALL&hl=en-US

Both the VFD-S series and VFD-M series are highly regarded workhorse drives. The M series is newer and a bit pricier than the S, and can be configured for use with higher hp motors. As best I can determine from checking online today, the S series tops out at 2 hp for 220/230v motors. See links below.

Wolf Automation's website prices the M series at $336 configured for 2 hp 220/230v motors, and at $486 configured for 3 hp motors. The S series is configurable for up to 2 hp motors (I can't find an option for a 3 hp application), and Wolf prices it at $290 for 2 hp 220/230v. The drive pricing and options calculator can be found here on Wolf's site for the M series: http://www.wolfautomation.com/Configure3.aspx?ProductID=23057&x=107&y=15

(http://www.wolfautomation.com/Configure3.aspx?ProductID=23057&x=107&y=15)and here for the S series: http://www.wolfautomation.com/Configure3.aspx?ProductID=23778&x=68&y=18

The S series has been used for years on the Jet 1642EVS and the PM3520B, both of which max at 2 hp. John's post notes that the Laguna Revo 2436 also uses it. That may be the case with the standard 2 hp motor. But the Revo 2436 has a 3 hp option, so I'm thinking they may use either the M series for that, or the alternative E series. The VFD-S drive is also used on the Grizzly G0632, which is similar to the Jet 1642EVS. (some folks refer to it as a "clone" but I think there are differences).

The M series is used on the G0766, the G0733, and some of the other Asian-made 18 x 47 lathes that are similar to the Grizzly G0733. I think (but have not confirmed) that this includes the Busy Bee Craftex CX 802, the Hare & Forbes Hafco WL‐46A, and the Baileigh WL‐1847VS.

BTW, just want to point out to readers who may not be familiar with Delta Electronics, Inc. it is not to be confused with the Delta brand of power tools and machinery. Completely unrelated.

[David C. Roseman]

David,


If the motor namplate gives the info, I would guess that is sufficient. If not, then measuring would be a involved process. To get full load amperage draw the rated full load rpm of the motor would need to be known. Typically a motor will run very near synchronous at no load, and wil slow to nameplate rpm's at full load.


Absent nameplate info, right or wrong, my method would be to measure the amperage on the single phase input because it is easier to access, and calculate the wattage input. To get full load, the frequency from the inverter would need to be adjusted to 60 cycles, no load speed measured, and then an adjustable brake method of some sort fashioned to load the motor until the full load 60 cycle rpm was reached. The amperage draw at that point x the input voltage would yield a value about 15% higher than the actual motor output.


I assume the motor is a nominal 1750 rpm full load 60 cycle motor. If so the synchronous speed would be 1800 for the motor, and the no load speed very near to 1800 rpm.


Horsepower is a factor of speed times torque. The torque a motor can deliver is for the most part a function of the rotor diameter and length. The slower the speed of the motor, the larger the rotor (and stator) need to be for the same horsepower output. With most current inverter powered wood lathes, the motors are oversped above nameplate rpm's and the advertised hp is with motor at the full load 60 cy rating. When the motors are running below 60 cycle rpm's, the horsepower is less, and when above 60 cycle rpm's the horsepower can be above namplate. Some inverters are capable of boosting motor torque at slower speeds to help compensate for a loss of hp at lower rpm's, but there is a limit to the boost.

I used to occasionally do some vibration analysis on rebuilt motors when still in the motor shop. To test a rebuilt motor, they (shop personnel) would couple the motor to a dynomometer and measure the amperage and torque curve as full load was reached. Methinks that is way to much trouble for what the answer is worth.

Thanks, Dale! Whew, measuring draw on these lathes is, in any event, clearly way beyond what I'm able to do. The things I learn on SMC!

[John Keeton]

David, thanks for the supportive comments on my work and wimpiness! To clarify, it was the Laguna Revo 1836 that had the S series VFD. I am not aware of which series is used on the larger 20 and 24" Revo lathes.

[Robert Henrickson]

As an aside, I must be doing something wrong or else a whimp turner. I have never stalled my Jet 1642-2. Nor have I attempted to.

Then I must be a real wimp -- I rarely stall my 1 1/2 HP 1642, even on 15" bowls from irregular blanks.

[Dale Miner]

Dale..........this is the motor label. Not sure it gives you all the info you want, but this is what they put on the motor.

321783

The label is lacking the info I was curious about. The "input power" part is especially confusing. Guess the question will remain unanswered.

[Geoff Whaling]

Interesting thread folks.


A couple of things concern me here -


1. obvious inaccuracies on the motor nameplate - re current draw.
2. poor ergonomic engineering design of the stand/lathe spindle height.


Grizzly's web site shows "Required power supply: 220V, single-phase, 15A." I have no reason to doubt Dale's technical knowledge and from basic power formula it would be apparent that the motor will definitely draw more than the 4 amps shown on the motor ID plate. This raises the question - will owners be tempted to install on 10 amp circuits? Potential fire hazard? Not sure about US law but it is incumbent upon manufacturers / suppliers / importers to supply factual information under Australian consumer and electrical safety laws.

Grizzly don't mention lathe spindle height, nor do many suppliers, but the "49-1/2" high" gives an indication to read between the lines. I'm 6'2" so not an issue for me but having such a high spindle height and fixed legs seems to be rather strange as a significant proportion of turners would find that height way to high to be comfortable or safe & are also "seniors." Installing a platform is not a good solution imo as it creates a potential tripping hazard & presents an unacceptable risk.

This begs the question - does Grizzly's design team care about the health and well being of the purchasers of their products? or is the price point more important?

You get what you pay for.

[Roger Chandler]

Geoff......I have my G0766 on a dedicated 20 amp circuit just for the lathe and nothing else. I have and would continue to advocate all turners use a dedicated circuit for their lathes of appropriate size wiring and breaker.

I might have to communicate with tech support @ Grizzly just to see how they can explain this configuration of amp draw/horsepower. I wonder if they even will answer the questions raised here? I am not putting them or the G0766 down.....I am actually very pleased with my unit's performance and features.......just interesting information for those who would like to be able to make technical comparrisons.

[Randy Red Bemont]

A lot of this has nothing to do with the original post. All he wants to know is if you own the 0766, do you like it. My answer is yes. It is a great lathe and my first lathe ever. This is what I am learning to turn on. Powerful and accurate. I would recommend it to a friend and already have.

Red

[david privett]

My g0766 had a bearing failure (noise) with only about 10 hrs on the machine when I removed them they were 6206 nsa brand (japan and only one failed) bearings, grizzly sent two Chinese bearings they have at least 50 hrs. no problem so far.

[David Walser]

A lot of this has nothing to do with the original post. All he wants to know is if you own the 0766, do you like it. My answer is yes. It is a great lathe and my first lathe ever. This is what I am learning to turn on. Powerful and accurate. I would recommend it to a friend and already have.

Red, I mean no offense, but, if this is your first lathe, how would you know if it is a "great lathe" or something else? My wife's first car was a used Chevy Chevette. She thought it was a great car.

[David C. Roseman]

Red, I mean no offense, but, if this is your first lathe, how would you know if it is a "great lathe" or something else? My wife's first car was a used Chevy Chevette. She thought it was a great car.

On the other hand, out of 54 posts so far, Red is one of the few responders who actually has a G0766. ;) The rest of us are offering our comments for what they are worth based on what we've heard or read. All useful input, IMO, to folks that may be interested in this new lathe.

[Mark Greenbaum]

I can recommend the G0766, and I own one. It is quiet - mine has run all of 5 minutes since I got it setup, and when it's sitting there it doesn't make a sound - even when it's running:-). And I cannot wait to actually turn a piece of wood on it!!

[Sparky Paessler]

I have the G0766 and it is my 4th lathe. started out with a little King Sealy (Craftsman) lathe. Moved up to a 1236 jet and then to a Nova DVR. Been turning for 15 years or so. This is my first Grizzly machine and I think that it is a fine lathe "for the money you pay for it". It does need a little tweaking out of the box to get everything right so if you are not into that then it is not right for you. Would I rather be turning on a Robust or a Oneway? Well of course but with my budget for a lathe that wasn't going to happen. The G0766 will allow me to turn anything I could on a "Better" lathe so it doesn't limit me there. I don't think the controls, banjo, Tailstock etc. are as smooth operation (just an opinion, not based on fact, I have not turned on the Nicer lathes) as they would be on a "better" lathe but they do work and don't limit me. I think it is great they have come out with a lathe this large and powerful that is in a price range that a lot more woodturners can afford. I really don't think I could tell someone "this is THE lathe you should buy" for any brand lathe. It all depends on what their circumstances are and what they are looking for. All I can do is report my opinion of how my lathe works for me and they will have to decide if that fits their needs or not. With that in mind here is what I found on my lathe after turning on it a couple months.

My lathe was delivered in good shape. I did not have any crate damage or loose parts in the crate rubbing on anything. Assembly of the lathe was fairly quick and simple (with two people) and most tools were provided. On power up lathe ran smooth. No unusual noises.

I did drill the banjo out to 1" to fit my aftermarket toolrests.

There is also the problem with the length of the Banjo. It will not pull out far enough for the 22" swing. Grizzly is suppose to be fixing that for us with a new Banjo.

I also had the Toolrest that came with the lathe shaft turned about 1" more up toward the top so that it would adjust down lower.

When I tried to screw on my Supernova chucks they did not seat all the way. A few minuets with the lathe on low and a file fixed this.

The hole thru the head stock had a spot about midway that my lamp rod for my vacuum chucks would not fit thru. a round file and low speed fixed this in a few minuets.

I am 5'10" and I did find the lathe a bit taller than I preferred. I thought about building a box to stand on but wanted some under the lathe storage so I ended up building a complete cabined filled with sand to replace the legs and made it the height I wanted. (See attached Picture.)

I have turned several hollow forms on it so far and roughed out a few bowls. My old DVR was the 220V version which was suppose to be 2.25HP (or so). My impression of this lathe is that it has more power than the DVR did. As a EE I agree that the motor can not be a 3HP if it only draws 4 amps. I will open mine up and put a meter on the motor leads and see what it really draws while roughing a large bowl (which should be a typical load.)

Overall For me and what I could afford right now I am very happy!

[David Walser]

Thanks, Sparky. That is a good review of the lathe. Very good information.

[Geoff Whaling]

On the other hand, out of 54 posts so far, Red is one of the few responders who actually has a G0766. The rest of us are offering our comments for what they are worth based on what we've heard or read. All useful input, IMO, to folks that may be interested in this new lathe.

David, very good point. Some comments are quite valuable as they may be based upon professional / technical knowledge &/or a sound understanding of hazards & potential risks.

On the Grizzly G0766 webpage there is a comprehensive specification PDF to download @ http://cdn2.grizzly.com/specsheets/g0766_ds.pdf Floor to center - height 47 13/16" ' & "Amps - 4A." The detail on the spec list is a credit to the importer. It’s a pity more lathes aren't provided with this level of info.

Are specs factual? Do they include the things we need to know? Do we understand what we are reading?

The “motor class” (class F) is presumably the NEMA “thermal class” of the insulation in the electric motor etc; the current shown on the motor name plate & in the specs is stated as “Full-Load current rating” (FLC). Most of the motor current tables I have checked show FLC in the order of 9.5 A for a 3hp (2.2kw) 3 phase motor at 220v AC. So what is the “4A” ??? It is about 40% of the commonly listed value???

The motor/inverter will draw a much higher current at start up – “Motor-starting current” or inrush current; and also at stall – “Motor locked-rotor current.” Single to 3 phase inverter/motor controllers – variable frequency drives - modify the “current draw” significantly depending upon the “dialled in” operating frequency of the motor which gives us variable speed control. Many of us will never understand the complexities of VFD's so we rely upon factual information being supplied to us. I guess the important information is the "Minimum Circuit Size - 15A."

The G0766 specs & motor label don’t state what testing standard these “specs” are tested to. The specs do state “CSA, ETL, or UL Certified/Listed – NO”. Has the lathes motor and associated wiring etc been tested for EMC compliance?

The manual is also quite comprehensive and well laid out. It offers additional advice such as "The full-load current is not the maximum amount of amps that the machine will draw." & "Circuit requirements in this manual apply to a dedicated circuit."

One matter that concerns me with the G0766, and many lathes of similar design, is the proximity of the motor to the turner in a normal turning stance & the lack of an “electro-magnetic compatibility” (EMC) certification on the identification plate & in the specs. Not an issue for the vast majority of turners as the interference the motor may cause is usually a nuisance only to them. However for turners with pacemakers or defibrillator / pacemakers the potential for “electro-magnetic interference” (EMI) from a 3 hp motor so close to the upper body is a significant hazard which may be life threatening in certain scenarios. Many turners give turning away once they receive a pacemaker or defib because of these potential hazards but they can still turn IF they manage the hazards with specialist advice and factual information.

Caveat lector.

[Sparky Paessler]

Ok I made some quick measurements when I got home. I put the lathe on the high speed belt setting. Using a Fluke 375 true rms clamp on meter I measured the no load current draw and the current draw when I put a load on the lathe. I measured both the 240 single phase input current to the inverter and the 3 phase output current.
At no load and at high speed the input side was drawing 3.8 amps when I loaded it it went up to 10 amps.
On one phase on the motor side I measured 2.2 amps no load and when I loaded it it drew 6.6 amps. I was probably not putting a full load on it and have no way of measuring how much I was loading it.
Did want to add that at high speed the inverter is putting out 118hz. With the belt in the high speed position 60hz is about 1670 rpm.

[Roger Chandler]

Ok I made some quick measurements when I got home. I put the lathe on the high speed belt setting. Using a Fluke 375 true rms clamp on meter I measured the no load current draw and the current draw when I put a load on the lathe. I measured both the 240 single phase input current to the inverter and the 3 phase output current.
At no load and at high speed the input side was drawing 3.8 amps when I loaded it it went up to 10 amps.
On one phase on the motor side I measured 2.2 amps no load and when I loaded it it drew 6.6 amps. I was probably not putting a full load on it and have no way of measuring how much I was loading it.
Did want to add that at high speed the inverter is putting out 118hz. With the belt in the high speed position 60hz is about 1670 rpm.

Sparky......glad you did the measurement. I felt like the amp on the label was probably wrong. A lot of things that come from overseas seem to not have everything labeled correctly......just try putting something together with instructions from over there! :D

As you have already found out like I have......this lathe does not lack for power! It performs very well, and I say that because of my previous experience on both the Powermatics and Jets and the one Robust AB. I felt like I had a valid basis of experience to draw accurate conclusions from, and this is also my 4th lathe, so I still feel really good about my purchase of the G0766.

Whatever anyone else decides on is their business and I wish them all well and hope they get their satisfaction as good as I have gotten mine with the G0766........ I would still do it all over again!

[hu lowery]

My 766 is getting a few hours on it and seems to perform just fine. I'm not having any issues with the spindle centerline height, I think they cleverly recognized that we would rapidly be standing on a thick mat of shavings and raised the spindle height to accommodate that! :rolleyes::D

I knew that Grizzly had stated that the four amps wasn't maximum draw but I am very glad to finally get some real numbers! My twenty amp dedicated circuit should be fine. Thank you Sparky, much appreciated! Pretty sure those numbers are pretty closely in line with the draw an electrical engineer has been saying would be needed for a three horse motor.

Hu

[david privett]

kinda going back to the power issue discussion , I am thinking about replacing my 1 hp 650 cfm vacuum with a larger one, so my motor nameplate states that it is 16 amp 1 hp motor 125 volt. So not wanting to overload things I thought to use a inductive amp gauge and see what that thing was really pulling. Well to my surprise it is using only 4 amps with the vacuum running with designed load of the vacuum's suction fan , all I can think of is that depending on the company some rate their products at full load amps (FLA I see this on most usa made motors labels) and some at start up amperage as stuff that is made in asia . That might explain some of the variance of consumed power requirements of the g0766 and others, not even going down the variable speed change road.

[David Walser]

... That might explain some of the variance of consumed power requirements of the g0766 and others, not even going down the variable speed change road.

It might explain some of the variance, but it doesn't explain the discrepancy. 4 amps simply cannot produce 3hp. You cannot get more energy out of a motor than what's put into it. No amount of efficiency improvements allows a motor to create energy. As a practical matter, because of friction losses, you cannot get out of a motor 100% of the power that's put into it. This is true of electric motors, gas engines, and steam engines. So, if the lathe has 3hp of power, the motor nameplate cannot be correct. Grizzly's known for using parts from older designs for new applications. Perhaps they recycled the nameplate from another motor?

This reminds me of how Sears used to rate their Craftsman tools by "peak horsepower". The number may have been accurate, but it was highly misleading. In this case, I assume Grizzly made an honest mistake with the nameplate. I cannot see what they'd gain by intentionally mislabeling the max draw and there are lots of potential downsides (in terms of product liability). While I'm curious what the real numbers are, for me it's a non-issue when it comes to making a purchase decision.

[Roger Chandler]

I spoke with one of the tech guys about this........first off, this stuff regarding inverters, and such is beyond my pay grade! :confused: Anyway, he says the single phase 220 power comes to the inverter which converts it to 3 phase power, which then goes to the 3 phase motor. He says it breaks it down, and that motor is indeed 3 hp, and draws 4 amps? [he said a lot of other things I cannot quote verbatim, cause I cannot remember them like he said them! ]

He sounded very much like he knows what he is talking about........I think someone who knows this stuff much better than I should be the one to communicate, because they understand the nomenclature and have the technical understanding that I do not possess. He was wondering how Sparky took his measurements of amp draw, when I said one of the turners measured it.

People he said, can write anything on a forum........which is true, but I think there are knowledgable folks here that have no agenda, but are trying to understand, and I think there are people who are considering this lathe that are becoming either confused or gun shy about it because of these posts. I sure would like to see the two things reconciled!

I have no interest other than factual information being available to all interested parties........owners need to be able to have confidence in their lathe, and prospective customers looking for reliable information should be able to have that as well. I just don't know how to get that information reconciled and here for all to see, and of course that is not my responsibility anyway, but I care that people have honest and factual information. I do not want to bring anything to this discussion that muddies the waters for anyone. Perhaps someone who has knowledge and integrity, with no agenda could inquire and maybe get reliable information..........maybe that information in the owners manual is reliable, but some are missing something????:confused:

All I really know from personal experience at this point is that my G0766 runs great, seems to have plenty of power and has already proven itself to me with some big heavy wood turned on it. Other than that, a lot of the questions in this thread I cannot reconcile.

I know the math does not seem to correlate to what is stated on the motor label......I guess I need to stop trying to be helpful on this.......cause it seems I have reached the limit of my current level of understanding.

Additional: I wonder if perhaps the 4 amp figure was put there by someone who thought the amp draw on each phase was 4 amps? Would that total 12 amps on 3 phases? I guess I am muddying the water, a bit with that question but, I am trying to figure out the disconnect on the label and the math...........I should probably just stop trying to do that! :rolleyes::D

[Dale Miner]

4 amps @220 volts 3 phase is about 1.3 to 1.4 hp.

http://www.engineeringtoolbox.com/elctrical-motor-full-load-current-d_1499.html

[Geoff Whaling]

I've created a new thread on power & VFD's.

[Sparky Paessler]

Roger

I measured the current draw with a meter that clamps around one of the supply wires (there are 3). It measured the magnetic field that builds up around the wire as current flows thru it and calculates the current from that. Very common way to measure current without having to break the wire and put the meter in series. Also after having read the user manual of the inverter unless they have completely locked out the keypad on the inverter you should be able to press the mode button until the display changes from F and the frequency to the A and the current is displayed. I will try that tonight. That doesn't affect any settings just changes what is displayed on the readout. From the readings I saw and 31 years of working with inverters and motors I feel that this is a 3hp inverter/motor setup. Cant explain the 4 amp rating on the label as the motor does draw more than that under full load. (looks like full load would be around 9 amps (which at 240VAC 3 phase would be 3hp).

Just a note on startup current. It is true that on Single Phase Motors the starting current is very high. They have a second winding (start winding) that is engaged on startup that draws a lot of current. The Start Cap shifts the phase of the input power so that the motor actually has two phases going to it which allows it to start spinning. When it comes up to speed there is usually a centrifugal switch that opens and the start winding is disconnected and the current drops down.
On a Three Phase motor there is not a start cap or a centrifugal switch. With three phases already the motor will start spinning without the cap or switch. Thus no extra windings are needed and the startup current is much closer to the regular running current. This is also one reason 3 phase motors are less expensive than same size single phase.

[Roger Chandler]

Roger

I measured the current draw with a meter that clamps around one of the supply wires (there are 3). It measured the magnetic field that builds up around the wire as current flows thru it and calculates the current from that. Very common way to measure current without having to break the wire and put the meter in series. Also after having read the user manual of the inverter unless they have completely locked out the keypad on the inverter you should be able to press the mode button until the display changes from F and the frequency to the A and the current is displayed. I will try that tonight. That doesn't affect any settings just changes what is displayed on the readout. From the readings I saw and 31 years of working with inverters and motors I feel that this is a 3hp inverter/motor setup. Cant explain the 4 amp rating on the label as the motor does draw more than that under full load. (looks like full load would be around 9 amps (which at 240VAC 3 phase would be 3hp).

Just a note on startup current. It is true that on Single Phase Motors the starting current is very high. They have a second winding (start winding) that is engaged on startup that draws a lot of current. The Start Cap shifts the phase of the input power so that the motor actually has two phases going to it which allows it to start spinning. When it comes up to speed there is usually a centrifugal switch that opens and the start winding is disconnected and the current drops down.
On a Three Phase motor there is not a start cap or a centrifugal switch. With three phases already the motor will start spinning without the cap or switch. Thus no extra windings are needed and the startup current is much closer to the regular running current. This is also one reason 3 phase motors are less expensive than same size single phase.

Hey Sparky.....thank you much for the explanation! I really do believe that your findings are accurate. I am not sure that the information given out by tech support is always in sync with the questions we are asking. They of course have a motivation to support whatever they put out, but independent analysts like yourself may ask questions that they are not necessarily comfortable with answering........just my thinking here! ;)

I have no doubt this is a 3 hp motor at all.......with as much turning as I have done on as many lathes as I have turned on, I can tell that the power and torque is there. I actually have a meter similar to the one in your picture [also made by Fluke] and it had not occurred to me to even test the power with it.

Could you tell me where in the line did you actually place your meter? Was it on the wiring at the receptacle, or did you take the cover off the inverter and hook your meter on the leads going into it?

Just so you know........I trust your background and your information!

[Sparky Paessler]

Roger

I took the inverter cover off and measured both 240v single phase hot wires going into the inverter. That is where I saw a max of 10amps. I also checked the wires going to the motor on the three phases side where I saw the reading of 6.6 amps with the loading I was using. That was the more important reading as it is the current going right into the motor. Thanks.




Hey Sparky.....thank you much for the explanation! I really do believe that your findings are accurate. I am not sure that the information given out by tech support is always in sync with the questions we are asking. They of course have a motivation to support whatever they put out, but independent analysts like yourself may ask questions that they are not necessarily comfortable with answering........just my thinking here! ;)

I have no doubt this is a 3 hp motor at all.......with as much turning as I have done on as many lathes as I have turned on, I can tell that the power and torque is there. I actually have a meter similar to the one in your picture [also made by Fluke] and it had not occurred to me to even test the power with it.

Could you tell me where in the line did you actually place your meter? Was it on the wiring at the receptacle, or did you take the cover off the inverter and hook your meter on the leads going into it?

Just so you know........I trust your background and your information!

[Sparky Paessler]

I did also just verify that with the inverter cover off you can press the mode button (I think it was 3 times to get to the "A") to display the amperage the motor is drawing.

[Jim Sevey]

Well- I'm confused. All I know is that I had a 1 1/2 HP lathe before I bought the 766. The 766 is dramatically more powerful and capable than my old 1 1/2 HP lathe. I'm happy with it. I'm glad there are knowledgable and curious people out there to keep the tool companies on their toes. You guys are way smarter than I am. Thanks for all the good information. That's what the Creek is for.

[Brice Rogers]

I am a new member and while I've read some posts here, this is my first time posting. I have been turning wood on a 9" craftsman lathe for about 3 years and finally bit the bullet and bought a Grizzly G0766.

I received my G0766 about 2 weeks ago. The crate was undamaged but the fasteners for the legs were laying in the bottom of the crate and the legs slide around during transit on the bed and removed some paint from one leg and scratched the bed. It is not terribly bad - - but disappointing. Two of the four bevel head screws holding the motor had fallen out and the other two were half unscrewed. The motor plate was only held by one of the two bolts, so the motor was "listing" and was close to falling off. Pardon the pun but the motor was hanging on "by a thread". The tail stock hand wheel wobbled because it was loose. That was all pretty easy to fix but disappointing for my major lathe purchase.

But then I took a look at the spindle. I discovered these things:
1. The threads were very rough looking and the leading and trailing edges had wire edges and were "torn" in a ragged fashion.
2. The spindle major thread diameter was out of spec for a class 2A - - With the wire edges, it measured 1.230". I think that it I would have touched up the threads to remove the burrs, etc. that the true measurement would have been closer to 1.225".
3. The unthreaded area at the base of the spindle was 1.260, which means that with some chucks, they won't seat all the way (there is a video of the G0733 by Harrison tools that mentioned the same thing.
4. The finish of the Morse taper looked rough, like the machine or machinist just took roughing cuts. In comparison the spur center and live center finish were much better.

I photographed the spindle and requested tech support send me a new and better one. They indicated that they were surprised with the lack of quality of the one I had. But tech support did not want to send me a spindle but instead wanted to ship me a 200 pound headstock assembly. I suspect that either they do not yet have spare parts or they doubted my ability to swap out the spindle. When I got it home, the roughness of the replacement spindle was a little worse and the diameter was even a tad smaller than the original one. Items 3 and 4 (above) were improved. In retrospect, rather than mess with freight shipping and pickup, I would have preferred to just dress the original spindle with a file, and sand paper. But it was undersize and I was reluctant to remove any more material.

So, here is my question for those people who have this new lathe. (1) What is the major diameter of your spindle threads and what is the surface finish like on the threads and morse taper ??? Am I just being too fussy? Is the quality of the spindle that I got representative of what Grizzly is shipping? I thought that the precision machined spindle threads should look at least as good as the finish on a $2.00 1" x 8 TPI bolt that I bought yesterday (BTW, the major OD of the 1" bolt was 0.996 which I thought was impressive and well within specs). If you have a better finish and size spindle, perhaps I should just wait until they get the bare spindle in stock as a spare part. I'm worn out from driving my pickup down to the freight yard (50 miles round trip). Looking for your thoughts.

322191322192

[Roger Chandler]

The spindle threads on my 0766 were in great shape, and when asked by another owner to measure it, I used a caliper and it measured precisely 1.25 inches in the threads.

[david privett]

yea the spindle threads are ruff , I would get on a list for a new one. maybe they can put it in the same package with the new banjo you will get.

[Dale Miner]

This is the first lathe I've seen that had chased spindle threads. All the others (and there have been many) have had ground threads.

It looks like the thread and relief areas were turned using very dull tools.

While the O.D. of the thread is under nominal, the pitch diameter is the more important dimension. That would require a set of thread wires to measure. When a chuck is screwed up to but not touching the unthreaded portion, does it seem like there is excessive loosenes in the fit between the spindle and the chuck (insert) threads?

[hu lowery]

This is the first lathe I've seen that had chased spindle threads. All the others (and there have been many) have had ground threads.

It looks like the thread and relief areas were turned using very dull tools.

While the O.D. of the thread is under nominal, the pitch diameter is the more important dimension. That would require a set of thread wires to measure. When a chuck is screwed up to but not touching the unthreaded portion, does it seem like there is excessive loosenes in the fit between the spindle and the chuck (insert) threads?


My first 766 had nice threads on the spindle. The second one had threads as described and add visible tearing of the threads where someone chased them in a hurry without adequate lubrication either. My thread OD was in tolerance but I doubt it still is after threading face plates and chucks on it a few times. The boss that trued up the chuck or face plate when it bottoms out was also very rough. I talked to Grizzly about this spindle because it looked to me like a cull that got back in the supply chain with a little work done to it in order to get by when they were trying to meet new lathe start up demands. The thread fit is very loose. I might have thirty percent contact or less just at a wild guess.

I decided to repair the second 766 I received, seemingly with bad bearings, turned out to be the rattling spacer I believe. Now I have a ticking noise back, only noticeable at low RPM. I suspect a loose set screw or two so I'll try tightening them.

If I thought I would get a better spindle than what I have I would probably kick up a fuss for one. My spindle had the torn ends left hanging along with everything else I mentioned. I cut hundreds of threaded shafts and threaded a bunch too when I was working in a short run production machine shop. After cutting threads a quick pass with a wire wheel takes care of the ends and the sharp threads. Nothing is going to help the extremely loose fit on the Grizzly spindle threads. I had the feeling that the threads had been damaged in some way and a sizing die that can be adjusted to smaller than standard size used to repair it by hand. The threads were rough and razor sharp when my lathe got here. I considered taking the boss down a little bit when my Oneway insert wouldn't fit but the Grizzly six inch faceplate fits so I turned a tenon on a piece of wood on a faceplate and mounted the chuck backwards on that to get to the insert with a Dremel tool while the lathe was turning to keep the hole in the insert round and aligned with the lathe spindle.

A lot of lathe for the dollars but the fun is going away for me. Like my craftsman with a Reeves drive, I seem to be spending more time working on the 766 than turning. My only consolation is that unlike the Reeves drive, once things are sorted on the Grizzly they will stay sorted.

Hu

[Brice Rogers]

This is the first lathe I've seen that had chased spindle threads. All the others (and there have been many) have had ground threads.

It looks like the thread and relief areas were turned using very dull tools.

While the O.D. of the thread is under nominal, the pitch diameter is the more important dimension. That would require a set of thread wires to measure. When a chuck is screwed up to but not touching the unthreaded portion, does it seem like there is excessive loosenes in the fit between the spindle and the chuck (insert) threads?

Yes, when I looked using magnification, I can see a lot of tearing; it looked like very dull tools. Either that or they were turning hot rolled steel which doesn't turn very nicely.

I checked the pitch diameter using a set of three 0.081" Fitch wires. The results that I got were a little puzzling. I measured 1.295 minus the added wire effect of 0.0536 equals 1.241. In the Machinery's handbook it says that the pitch diameter should be between 1.2292 and 1.2221. What I measured was at least 0.012 over that. Hmmm..... (this is the first time that I've used wires and I repeated my measurement three times. I can see why people don't like to use them...)

I only have the cast iron faceplate to check thread looseness. I don't have any confidence that the faceplate was made to any particular standard. And yes, it does wobble up to the point that the rough casting comes in contact with the spindle register. It wobbles about as much as my $2 1"x8TPI bolt and nut.

When I look at the thread profile, the flat at the top of the crest is very wide. That is, it is about 0.030". The "book" says that it should be 0.125 x pitch or about 0.016".

So, maybe they turned the spindle pitch diameter slightly oversize, realized that it might be tight with the thread crest (having an interference in some situations) and to correct it they ground off about 0.020 of the major diameter? Looking at my spindle it looks like someone took aFrom a previous thread (pardon the pun), it has been reported that some of the spindles look good and one person measured 1.250 inchs diameter. So, maybe they found that to be slightly tight and then had someone (perhaps with poor tools and/or machining skills) re-work the spindles. Also, on the beginning of the thread on my own spindle, I can see that the edge of the thread has been pushed over the original chamfer (dull tool that pushed the metal rather than cutting it. That might account for the reports of sharp wire edges and tearing.

In most factories, when it is necessary to rework a part, that there are records kept for this operation. Perhaps Grizzly's engineers have this knowledge of why these spindles look reworked.

I would be satisfied if Grizzly would be able to send me a nice looking and in-spec spindle. I would swap it out when I need to replace the shielded (not sealed) bearings.322279

[Geoff Whaling]

When items such as lathes are manufactured to be retailed at a price point - something has to be sacrificed. Quality of components, stock material, machining, bearings etc; specification for component durability, duty cycles of electric motors etc all get spec'd down to meet the price point. "Name" manufactures can also make mistakes and they are usually very quick to rectify the situation & make good.

I can't say that I am at all surprised by many of the comments on this post. I've had a good look at quite a few "generic" lathes to check the quality of machining, castings, design etc - all I can say is that I am glad I am fortunate enough to be able to afford a Vicmarc. Not snobbery at all - I reason that I have worked hard enough so its about time I enjoyed a "quality" machine in my leisure time.

[Roger Chandler]

I must be blessed or something......my G0766 seems to be right in all respects, not withstanding the new banjo being made and on its way. The only issue I had was the rpm sensor vibrated loose during transport across the ocean, which was a matter of putting the retaining nut back on and tightening it. Mine has had none of these problems. The head stock was a little loose in the crate, now that I think about it, but nothing that affects the performance of the lathe once set up and running.

[Brice Rogers]

I must be blessed or something......my G0766 seems to be right in all respects, not withstanding the new banjo being made and on its way. The only issue I had was the rpm sensor vibrated loose during transport across the ocean, which was a matter of putting the retaining nut back on and tightening it. Mine has had none of these problems. The head stock was a little loose in the crate, now that I think about it, but nothing that affects the performance of the lathe once set up and running.
Roger, if you don't mind me asking: (1) what was your date of manufacture (it is written on the front of the lathe below the main headstock and (2) what is the major OD of your 1-1/4 threads?

Yes, I think that some people were blessed (perhaps the first people to get their G0766) and some people were not (perhaps the more recent deliveries). I had learned on and worked with a $75 9" Sears craftsman lathe for 3 or 4 year and after having done a ton of research decided to go for my first piece of brand new shop equipment. I had high and - - in retrospect - - perhaps unreasonable expectations.

[Roger Chandler]

Roger, if you don't mind me asking: (1) what was your date of manufacture (it is written on the front of the lathe below the main headstock and (2) what is the major OD of your 1-1/4 threads?

Yes, I think that some people were blessed (perhaps the first people to get their G0766) and some people were not (perhaps the more recent deliveries). I had learned on and worked with a $75 9" Sears craftsman lathe for 3 or 4 year and after having done a ton of research decided to go for my first piece of brand new shop equipment. I had high and - - in retrospect - - perhaps unreasonable expectations.
I am out of my area at present and do not have access to my lathe to look at the label, but if I recall, it was manufactured in March 2015......serial number is number 00041 I think [from memory].

I measured the outside diameter of the threads......it was 1.25 inches.....with a caliper. Maybe 1/2 of .001 under, but all my 7 chucks and faceplates fit well and run true on it........hope that helps.

[Mark Greenbaum]

I had to shave the flat section of the spindle down a bit for my new NOVA Adapter to be able to snug up against the shoulder of the spindle. Once I did that the adapter and the NOVA G3 chuck run very smoothly. Maybe .0005 TIR which I will verify this week. I turned a curved limb section of Bald Cypress (about 2" off center at mid point) and had no hop, no problems whatsoever (except the Grizzly provided live center made a whining noise under pressure). It was so nice to turn at home and not have to chase the lathe down the driveway.

[Brice Rogers]

Yes, that helps. Mine was built in June and delivered in early to mid Sept. It seems like the first batch had nicely machined spindles and (this is an educated guess), they eventually found that running too close to the nominal 1.2500 (and perhaps with an oversize "pitch diameter") was causing some interference problems. So I am guessing they took a fairly rough cut across the threads, and/or re-chased the threads. I'm hoping that Papa Grizzly, Shiraz Balolia. might look at my pictures and reads this thread and might comment on whether rough looking and undersized threads are to be considered acceptable for this level of lathe or whether they experienced a manufacturing problem of which the US is not yet aware. Similar equipment in my shop (Atlas Craftsman lathe, Sears Lathe, Harbor freight lathe) seem to have much nicer looking threads.

[Roger Chandler]

It is my guess that Grizzly needs to make sure the quality control process at the factory is tightened up a good bit before units are shipped!

[Dave Mcintire]

For what its worth, I measured the spindle on my 3520 A model and it measured 1.231" over the threads and 1.065" on the flat behind the threads. There may be a slight bit of wear as this machine has been used ( lightly) for a few years.

[hu lowery]

It is my guess that Grizzly needs to make sure the quality control process at the factory is tightened up a good bit before units are shipped!


Roger,

Don't forget that Grizzly is just the customer. Although a large customer I suspect they aren't the largest nor do they account for a major portion of the Burt Group's income. While Grizzly obviously has some say-so, Burt calls the shots. The 766 design has been on the market since 2012, Grizzly was just the ones to purchase it in probably 2014.

I have seen the same thing going on with chinese manufactured items for decades. Toys with lead and cadmium in the paints? The manufacturer says not their fault. The customer was only willing to pay "X" amount per unit and the only way the factory was able to meet that price was to cut corners. I suspect the same is true with Grizzly. While they have a lot of say-so and some oversight they don't have control of every detail like they would if they manufactured the lathe. The Grizzly tech support guy told me he was 100% certain that the spacer didn't belong in my lathe so I left it out. Now I am debating do I tear the headstock down yet again to put the spacer back in?

Five or ten years from now these early aggravations with the lathe will be long forgotten while it still gives great service I suspect. At the moment, the issues are getting old! Went to use a one inch skew yesterday and couldn't get it in the position I would normally use to turn with it, tool post too tall. We know that is getting fixed but that didn't help things any yesterday. May see if I can bum some machine time this week to turn the toolrest down and open up the banjo. When you turned the shaft on the tool rest down to drop another inch lower, did you have to shorten the post also or did it clear the lockdown shaft still?

Hu

[Brice Rogers]

Hu, I think that if you can turn down the upper portion of the tool post shaft that you do not need to modify the standard banjo. I think that you'll get a lot of improvement but am uncertain whether you need to wack off a bit on the bottom of the tool post - - but that's very easy to do.

I have a 12" metal lathe (Atlas) but it isn't big enough to spin the tool rest. I think that you might need a lathe with about an 18" swing over the cross slide. I'm thinking of using my Rong Fu-30 mill and try to mill off the shoulder of the tool post with some sort of fixturing to allow me to rotate the tool while I'm milling. If I get to that point, I'll probably take off about 3/4 inch from the shoulder.

[Roger Chandler]

Hu, I took off 3/4" off the step area up that shaft underneath the rest........in my opinion, 5/8 would have been ideal. There is plenty of room for the post down in the banjo hole once that mod is done. No issues with bottoming out.

[David C. Roseman]

Hu, I think that if you can turn down the upper portion of the tool post shaft that you do not need to modify the standard banjo. I think that you'll get a lot of improvement but am uncertain whether you need to wack off a bit on the bottom of the tool post - - but that's very easy to do.

I have a 12" metal lathe (Atlas) but it isn't big enough to spin the tool rest. I think that you might need a lathe with about an 18" swing over the cross slide. I'm thinking of using my Rong Fu-30 mill and try to mill off the shoulder of the tool post with some sort of fixturing to allow me to rotate the tool while I'm milling. If I get to that point, I'll probably take off about 3/4 inch from the shoulder.

Brice, if your Atlas can swing a full 12", why not just trim 1" off each side of the 14" stock rest, and turn down the shaft yourself. The stock rests are the vintage, tried and true cast iron design and not expensive if you ever decide you really need 14". 12" is much more useful for most projects, IMO. And if you eventually upgrade to the Robust or similar rests with the hardened steel rod, you may even decide to cut the original down further for small projects. When I bought my G0733 three years ago, I ordered several extra of the 14" stock rests and cut them to various lengths, down to 7". They work fine, but I've since gone to Robust simply because the hardened rod makes them smoother and virtually maintenance free.

[Brice Rogers]

1. David, your idea has merit. Thanks. I'll need to check my lathe to see if it would clear the saddle and to see if I can position the cutter between the lathe chuck and the "wings" to the wood lathe tool rest top. I would be chucking up on the 25 mm shaft. When I envision this turning operation I'd want to think it through because the top of the spinning tool rest could cause a lot of damage if I got any body parts in the way. I'm usually cutting/turning to the right of the spinning part.
2. Even if I don't turn down the original 14" tool rest, your idea is good for buying some replacement tool rests and cutting them down. Yes, I will need a number of narrower ones. On my 9" craftsman I had built a variety of different tool posts including some curved ones.
3. On a side note, you mention that you have a G0733. As best I can tell, there is a fair chance that the spindle used in the 0733 may be interchangeable with the 0766. Right now Grizzly isn't showing very many spare parts for the 0766. IF the 0733 spindle actually IS interchangeable and IF the spindle is of higher quality (smoothly cut threads, proper size, etc.), perhaps it would be a good swap out. What is the quality of your spindle? Also, have you heard if any of the 0733's that have recently been shipped have had any negative changes in what they're shipping?

[hu lowery]

Hu, I took off 3/4" off the step area up that shaft underneath the rest........in my opinion, 5/8 would have been ideal. There is plenty of room for the post down in the banjo hole once that mod is done. No issues with bottoming out.


Roger,

Thank you for the information. My week has went sideways on me anyway but I'll remember this for future reference.



Brice,

I wasn't real clear in that post. Opening up the banjo wasn't directly related to turning down the shaft on the tool rest. I am making a pretty common modification, opening up the diameter of the hole in the banjo a little to take one inch tool rest shafts.

Hu

[David C. Roseman]

[snip]
3. On a side note, you mention that you have a G0733. As best I can tell, there is a fair chance that the spindle used in the 0733 may be interchangeable with the 0766. Right now Grizzly isn't showing very many spare parts for the 0766. IF the 0733 spindle actually IS interchangeable and IF the spindle is of higher quality (smoothly cut threads, proper size, etc.), perhaps it would be a good swap out. What is the quality of your spindle? Also, have you heard if any of the 0733's that have recently been shipped have had any negative changes in what they're shipping?

Brice, FWIW, the outside diameter (I believe it's technically called the "major" diameter) of the spindle threads on my 3 y/o G0733 is 1.238", measured with both digital and dial calipers. The threads are cut cleanly and fully formed, with no flats on the crests. Here's a pic taken this evening:
322442
The morse taper portion of the bore is smoothly machined. I don't know whether all G0733's have shipped this way, but I've not seen or heard of thread and bore issues like those on your G0766.

As for swapping a G0733 spindle into your G0766, that's a creative thought, but you would lose the ability to mount the factory handwheel that came with your lathe. The G0733s do not ship with handwheels, and the spindles do not protrude beyond the outboard wall of the headstock casting to allow easy attachment of one. Looking at the parts diagram for the G0766 on Grizzly's site, it looks like the spindle on your lathe does, as the factory handwheel appears to attach to the spindle with set screws.