G0766 - Sounds

[Roger Chandler]

On one of the other threads I read last night and this morning, there were questions regarding the "sounds" or "noises" that come from the new G0766.

I began my third project this morning since receiving my unit. [life has just been too busy! I wish I could have done at least a dozen by now! ] This mornings project was the biggest blank I have put on the lathe so far, and probably weighed about 25 lbs to start with and was not balanced, as it had a flat on one side and one end of the blank was bigger than the other end as well.

This G0766 handled that unbalanced blank with such smoothness, that I was impressed all over again! ;) Now my shop building has wooden floors and it is a utility building and the joists underneath that 3/4" plywood are just 2x4's so my setup is far from optimal as far as vibration resonating from anything unbalanced.

As to the sounds coming from the 0766.........I took the time to make sure my air cleaner, and any other machine was off, and I listened carefully to the sounds made during the rough out. What I noticed is what I have stated before........the more I use this machine, the quieter is seems to run.......it was the same with my former G0698. This mornings blank had the most weight so far on this lathe, and while running, there was just the motor fan......[totally enclosed fan cooled- TEFC] and a small hum from the inverter, which I think is totally normal and designed that way.

You may recall, I have had opportunity to turn on a Robust American Beauty that belongs to a friend and have turned to date on 9 different 3520b lathes [some more than once as they are owned by the respective clubs I belong to] and several Jet 1642 evs units. To me.........this G0766 puts off about the same sounds as most of the 3520b's I have turned on.

I think there is a definite break in period with any machine as it settles into its own patterns of wear and also like a car, gets used to the main driver......call it settling or whatever you want, but it is true. What I do know is that my unit is quieter than the first day I got it, and seems to be running smoother as I turn new projects on it.

For those who have just gotten their units, and wonder about the sounds you hear.........give it a little time and I think you will see that the same pattern of settling in occurs and your lathe will likely give you more confidence every time you do a new project!

[Roger Chandler]

I forgot to mention the belt getting broken in as well as the lathe gets used.......that will also lend itself to more smoothness and quiet.

[Jim Norell MN]

Roger, I see now you have responded to my questions about the sounds I'm hearing, I appreciate your help. I'm just curious if my lathe sounds normal, it seems to run very smooth, just a high pitch squeal and chirping. Not real loud, a little annoying though. I hope your right and it will quiet down as it breaks in. I posted a link on another thread, I'll copy it here also. Thanks again.

https://youtu.be/5rcUi9HOHdg (https://youtu.be/5rcUi9HOHdg)

[Mark Greenbaum]

That sounds pretty darned quiet to me. I've only used a couple larger lathes, and this sounds normal to what I've heard from PM 3520b's and Jet-1642-EVS-2's. My old Greenie Shopsmith would drown that puppy right out like Blue Cheer and the Wall of Sound (Rock 'n' Roll reference).

[earl timmons]

Jim I sent you a message I have both a 3520 and the 18 inch version of your lathe in my shop in Mn contact if your within a reasonable drive

[Mike Goetzke]

Roger, I see now you have responded to my questions about the sounds I'm hearing, I appreciate your help. I'm just curious if my lathe sounds normal, it seems to run very smooth, just a high pitch squeal and chirping. Not real loud, a little annoying though. I hope your right and it will quiet down as it breaks in. I posted a link on another thread, I'll copy it here also. Thanks again.

https://youtu.be/5rcUi9HOHdg (https://youtu.be/5rcUi9HOHdg)


Is it just me - that don't sound right.

I would send a link of the video to Grizz.

mike

[Cary Falk]

That sounds like what my Jet 1642 used to sound like.

[Jeffrey J Smith]

Sounds to me like the fan may be hitting something...while it doesn't sound serious, it doesn't sound right either. I'd send this off to Grizzley, too.

[James Conrad]

It doesn't sound right, same feedback whine in the motor/lathe I sent back. All the other sounds of the fan and spindle winding up sound ok, but that distinctive whine that changes pitch at about 450rpm is off.

[david privett]

I hate to bring this up but.... I had a noise on my g0766 I used a mech stethoscope and isolated it to the spindle I called griz. and they said they have no records of noises in the machines, ok I was thinking, so I started to pull the spindle and seen in the bearing housing had quite a bit of casting sand it there. I had to use more force than I would have liked to get the shaft out. Removed the bearings and one nsk 6206z bearings was noisy. I called griz. and explained that I needed 2 new bearings which they sent quickly. I installed the new bearings into a clean housing and using a lubricant in the housing and bearing surfaces that touch which made installation much easier. So I do not know was the bearing failure due to sand, beating them in dry or a bad bearing from the nsk factory. Anyway it runs very smooth and very quite now . now issue two. Before I got the new bearings I was talking to tech. help and asked them what was the factory gap between the rpm pick-up and the pulley with the trigger magnets. He said use a business card to set the gap. ok I was thinking again. I measured the gap before I pulled the sensor and it was .050 inches, but I set it with a business card thinking someone knew what they were talking about. All I read was 0000 no matter what speed it ran quietly at. So I reset it to .050 inches now it reads only about 1/3 of the what I believe it is turning . Could some of you get your feelers and read what your factory gap is please post .Thanks Dave

[Roger Chandler]

Roger, I see now you have responded to my questions about the sounds I'm hearing, I appreciate your help. I'm just curious if my lathe sounds normal, it seems to run very smooth, just a high pitch squeal and chirping. Not real loud, a little annoying though. I hope your right and it will quiet down as it breaks in. I posted a link on another thread, I'll copy it here also. Thanks again.

https://youtu.be/5rcUi9HOHdg (https://youtu.be/5rcUi9HOHdg)


If you are concerned about the fan, just remove the screws holding the fan cover in place on the end of the motor and check to see if the fan is tight on the shaft and check the fins on the fan to see if they are rubbing on anything. If the set screw is loose, it could have allowed the fan to slip one way or another and rub on something........otherwise, yours sounds okay to me................

That being said, it is extremely difficult to tell something with a phone picking up the sound or even a video camera. If I were concerned, I would check the above out, and if all is well in that area, the inverter sounds pretty much to me like mine and most of the 3520b's I have turned on.

I did turn on one 3520b that was one of the first to come out, and I think was before they started producing them over in Taiwan..........it belonged to a member of our club [Dr. Glick] His was unusually quiet, and the only one I have been around that was absolutely whisper quiet. The 3520b has been out for a number of years now, and I have turned on one that was really noisy.......much more so than my G0766, but most of them sound pretty similar to my G0766!

[Mike Peace]

I knew a turner that bought a new Jet 1642 and was very concerned about it being what he judged as "loud and noisy". I suggested he come to a hands on turning session at another club I belong to which has a Jet 1642 so he could listen and compare. He did and said it sounds about the same. I never noticed the Jet sounding much different than my PM3520. I guess the point is that we all have a different expectation for what a new lathe should sound like. Sometimes it just takes getting used to.

[Roger Chandler]

I just went out to the shop and took the fan shroud off the end of the motor on my 0766.........just to check it out. It seems the fan is held in place by a bolt on the end of the motor shaft, and not by a set screw as I had thought and spoke to in the earlier post in this thread.

The bolt has sort of a flat head on it, but one can get a wrench on it and see if it is tight........I would not put too much pressure on the hub of the fan because it is made of nylon, and you do not want to over-tighten! Just in case you suspect your fan may be loose......mine is tight.

One additional thing........the fan shroud has some room for adjusting in the screw slots......I would encourage you to maximize your clearance on the fan by pulling outward just a little .......no need to take the screws all the way out to do that, just loosen them, and make sure one side of the shroud is not pushed in a wee bit......if anything is rubbing that might solve a problem if it is that one.

[Jim Norell MN]

I appreciate everyone's input, I'm not too concerned with the sound, it's not that loud. I removed the belt and isolated the sound to motor or vsd. I removed the fan cover, everything looked good back there, sounded the same with cover removed. By hand the motor spins free and quiet. I did send Grizzly another message and included the link. They have a replacement tool rest on the way, I'm just going to start turning and see how it goes.

[Roger Chandler]

I knew a turner that bought a new Jet 1642 and was very concerned about it being what he judged as "loud and noisy". I suggested he come to a hands on turning session at another club I belong to which has a Jet 1642 so he could listen and compare. He did and said it sounds about the same. I never noticed the Jet sounding much different than my PM3520. I guess the point is that we all have a different expectation for what a new lathe should sound like. Sometimes it just takes getting used to.

Good point Mike! I think most of what is being described is inverter/motor sounds. There is definitely a little belt noise as well as it travels over the pulleys............while I was out checking a minute ago, I also took the belt off the pulleys and just listened to the motor and inverter without the belt noise..........it sounds normal to me!

I am not saying that a unit could not have issues.....obviously James's unit did and they are replacing it, but from what I can tell from everyone else's posts, the units are performing well so far.

[Roger Chandler]

I hate to bring this up but.... I had a noise on my g0766 I used a mech stethoscope and isolated it to the spindle I called griz. and they said they have no records of noises in the machines, ok I was thinking, so I started to pull the spindle and seen in the bearing housing had quite a bit of casting sand it there. I had to use more force than I would have liked to get the shaft out. Removed the bearings and one nsk 6206z bearings was noisy. I called griz. and explained that I needed 2 new bearings which they sent quickly. I installed the new bearings into a clean housing and using a lubricant in the housing and bearing surfaces that touch which made installation much easier. So I do not know was the bearing failure due to sand, beating them in dry or a bad bearing from the nsk factory. Anyway it runs very smooth and very quite now . now issue two. Before I got the new bearings I was talking to tech. help and asked them what was the factory gap between the rpm pick-up and the pulley with the trigger magnets. He said use a business card to set the gap. ok I was thinking again. I measured the gap before I pulled the sensor and it was .050 inches, but I set it with a business card thinking someone knew what they were talking about. All I read was 0000 no matter what speed it ran quietly at. So I reset it to .050 inches now it reads only about 1/3 of the what I believe it is turning . Could some of you get your feelers and read what your factory gap is please post .Thanks Dave

I did not use a feeler gauge on mine, but you may recall that my rpm sensor was out of position just dangling on its wire when I got the lathe.........I just eyeballed the distance and think it is about 1/32 nd of an inch that I set mine....at least that is what I was going for, and my rpm's match what is stated for the low and high belt settings on the outside of the door, so I think I got it pretty close for a guess.

[David C. Roseman]

Jim, to me the high-pitched whine sounds like it is drive-related. The VFD on that lathe is the Delta Electronics VFD-M series AC motor drive, (1-phase, 230V AC, power range .5 - 7.5 HP). It is an excellent drive, with 157 programmable parameters. (I think the user keypad is locked out at Grizzly's factory in Shandong to prevent tampering. So to adjust parameters, it's necessary to go in through the computer interface using the Delta VFDSoft software and a special cable, not something I recommend while under Grizzly's warranty :)). My three-year-old G0733 has the same drive, and there has never been such a whine. But it uses a 2 HP motor, rather than a 3 HP. Don't know if that might make a difference. I'll be interested to see if other G0766 owners are experiencing the same whine. If so, it may be a parameter setting. One of the parameters is Pr. 71, PCM (pulse-code modulation) Carrier Frequency, with an adjustment range of 0 - 15. The Delta factory default setting is 15 for maximum heat dissipation. A frequency setting that high might conceivably be the source of the whine, if it was not adjusted down at the time the lathe was assembled. The drive is designed to handle HP from .5 to 7.5, so there should be plenty of room for adjustment for a 3 HP motor. Just brainstorming on this.

[David C. Roseman]

I hate to bring this up but.... I had a noise on my g0766 I used a mech stethoscope and isolated it to the spindle I called griz. and they said they have no records of noises in the machines, ok I was thinking, so I started to pull the spindle and seen in the bearing housing had quite a bit of casting sand it there. I had to use more force than I would have liked to get the shaft out. Removed the bearings and one nsk 6206z bearings was noisy. I called griz. and explained that I needed 2 new bearings which they sent quickly. I installed the new bearings into a clean housing and using a lubricant in the housing and bearing surfaces that touch which made installation much easier. So I do not know was the bearing failure due to sand, beating them in dry or a bad bearing from the nsk factory. Anyway it runs very smooth and very quite now . now issue two. Before I got the new bearings I was talking to tech. help and asked them what was the factory gap between the rpm pick-up and the pulley with the trigger magnets. He said use a business card to set the gap. ok I was thinking again. I measured the gap before I pulled the sensor and it was .050 inches, but I set it with a business card thinking someone knew what they were talking about. All I read was 0000 no matter what speed it ran quietly at. So I reset it to .050 inches now it reads only about 1/3 of the what I believe it is turning . Could some of you get your feelers and read what your factory gap is please post .Thanks Dave

Dave, hmm, did the rpm display read correctly before you pulled the spindle? When you had the spindle pulley out, were you able to see all three rare-earth button magnets in place? I ask because they are glued in, and if one or two popped out during your disassembly, the pick-up would read a lower rpm than actual. If two popped out, it would read 1/3 of actual, I'm thinking.

As for the gap measurement, I'd just adjust the pick-up so that it's as close to the pulley as possible without touching when you turn the spindle by hand. I'll check clearance on my G0733 with a feeler if you'd like, as I assume the pick-up and pulley are the same as on the G0766. But the business card advice sounds right to me. Simply need to be close enough for the magnetic field to pulse the pickup.

[david privett]

yes it did work before bearing replacement and on mine the magnets are not glued in they just sit in holes in the pulley , I found that out when I sat the pulley down and they stuck to the bed of the lathe. Could those magnets be directional? I contacted griz. and they have no specs on the air gap they are getting with burt co. to find out what it is supposed to be. I contacted someone who has a g0733 and he gapped it at .053 inches.

[David C. Roseman]

yes it did work before bearing replacement and on mine the magnets are not glued in they just sit in holes in the pulley , I found that out when I sat the pulley down and they stuck to the bed of the lathe. Could those magnets be directional? I contacted griz. and they have no specs on the air gap they are getting with burt co. to find out what it is supposed to be. I contacted someone who has a g0733 and he gapped it at .053 inches.

I think you may have nailed it. If you happened to reverse two of the magnets when reinserting them, seems to me they would no longer strobe the pick-up as the pulley spun. So the pick-up is being pulsed once in each rotation rather than three times, and would think the spindle is turning at 1/3 its actual speed.

My theory may not be right, but I like it! :)

[david privett]

I will try to flip them over getting the correct direction since they are unmarked this could be a test of patience, I will look for any change in readings to see if I am getting anywhere. thanks

[David C. Roseman]

I will try to flip them over getting the correct direction since they are unmarked this could be a test of patience, I will look for any change in readings to see if I am getting anywhere. thanks

By the way, nice job pulling the spindle and replacing the bearings. You do realize, I hope, that you are now the go-to guy on SMC if any G0733 or G0766 owners need help doing this in the future! :cool:

[Thomas Canfield]

On one of the other threads I read last night and this morning, there were questions regarding the "sounds" or "noises" that come from the new G0766.

This G0766 handled that unbalanced blank with such smoothness, that I was impressed all over again! ;) Now my shop building has wooden floors and it is a utility building and the joists underneath that 3/4" plywood are just 2x4's so my setup is far from optimal as far as vibration resonating from anything unbalanced.

Roger- You can take some of the "flex" out of the plywood by using a flat 2x6 or larger under the legs that will span the joists. The legs of the lathe need to be sitting on something more than unsupported plywood or you get the drum effect. A friend had a 3520B in a portable building and he had to change the orientation of lathe and add the additional 2x under legs to get away from the flex.

[Roger Chandler]

Roger- You can take some of the "flex" out of the plywood by using a flat 2x6 or larger under the legs that will span the joists. The legs of the lathe need to be sitting on something more than unsupported plywood or you get the drum effect. A friend had a 3520B in a portable building and he had to change the orientation of lathe and add the additional 2x under legs to get away from the flex.

Good idea, Tom...Thanks! With the way my building sits, getting underneath is not an option, but stiffening with something on top is. I did not mean that my floor was unsupported......it is, but with relatively small joists, and it sits on a gravel pad. A combination of some 2x4 and 4x4 lumber. I have the legs directly over the seams in the plywood and over a couple of joists, but still I know there is some resonance occurring.

[david privett]

well got lucky there were two magnets I guess that were reversed from what the pick up wanted to look at, weird. They did not feel like there was any repulsion as if you were mixing magnetic fields, I would think you would feel it once you placed the first magnet in the iron pulley if there was a reversal. but I am good to go now Later on Dave

[daryl moses]

Glad you got it fixed Dave. You are a patient man.
Have a brew on me!!

[david privett]

for those who want to note it in there g0766 manuals griz called me today and said the correct air gap clearance for the rpm sensor to pulley magnet is .052 inches. I will have a least 2 daryl I have a image that I must maintain.

[David C. Roseman]

Roger, I see now you have responded to my questions about the sounds I'm hearing, I appreciate your help. I'm just curious if my lathe sounds normal, it seems to run very smooth, just a high pitch squeal and chirping. Not real loud, a little annoying though. I hope your right and it will quiet down as it breaks in. I posted a link on another thread, I'll copy it here also. Thanks again.

https://youtu.be/5rcUi9HOHdg (https://youtu.be/5rcUi9HOHdg)


I'm bumping this thread to add info that might prove helpful to Jim Norell and any other G0766 owner who experiences the high-pitched chirp, actually more a trill, that Jim recorded in his youtube video.

In post #17 a few months ago, I speculated that this whine might just be a matter of adjusting a parameter setting in the Delta VFD-M Series drive, specifically pr. 71 ("Pulse Width Modulation Carrier Frequency"). But I didn't have a G0766 back then, so couldn't confirm it. Last month I added a G0766 to my shop, and, lo and behold, I heard an almost identical trill from it, starting at about 410 rpm and above. The sound doesn't interfere with performance, and in fact some folks can't really even hear it, depending upon their sensitivity to very high frequency sound. But it was enough to annoy me, so I investigated further.

What I found is that, in my case, and I'm virtually certain in Jim's as well, the trill is simply acoustic noise (as distinguished from electromagnetic noise) from the motor that can be silenced by a small change in the setting of pr. 71 in the AC drive.

From pp. 4-51 and 4-52 of the Delta Electronics owner's manual for the M-Series AC drives (rev. Oct. 2014), the range of available values for pr. 71 is 1 to 15, 15 being the highest frequency setting, 15KHz, and 1 being the lowest, 1KHz. The Delta factory default setting is 15, which yields the maximum heat dissipation of the AC drive and the lowest acoustic noise from the motor, but the highest electromagnetic noise. So there is a trade-off in the type of noise induced depending upon the selection of the parameter value. Dialing it down decreases electromagnetic noise but increases acoustic noise induced in the motor.

On my G0766, I found that the actual as-delivered setting for pr. 71 was 8. That is right in the middle of the range. So, at some point in the lathe's production, the Delta Electronics default value of 15 was reset to 8, and I'm guessing that this is done as a compromise. The Delta owner's manual further states for pr. 71: "The carrier frequency can be increased when required to reduce motor noise." (p. 4-17).

Based on this instruction from the manual, I simply adjusted the value for pr. 71 to 10, rather than 8, and the annoying whine completely disappeared. My G0766 is now almost whisper quiet, just like my 3 y/o G0733.

The Delta manual further explains that VFD-M Series drives have 157 user-adjustable parameters, and a keypad for making easy adjustments. However, I have learned that for whatever reason, the functionality of the keypad is locked out at some point in Grizzly's production process. I am surmising that this is to avoid uninformed tampering with settings. I understand this concern, but the result is that lathe owners are not easily able to make corrective adjustments, and the Grizzly tech folks in Springfield are unable to guide the owner through adjustments by phone.

I was able to make the corrective adjustment myself by connecting a laptop to the AC drive using the drive's RS485 telecommunications port and a special adapter, and the Delta VFDSoft software (ver. 1.48) downloadable online. While I was connected through the interface, I made one additional parameter change. By changing the value of pr. 01 ("Source of Operation Command") to 00, I re-enabled the keypad functionality. If future adjustments are necessary or desirable, they can be made through either the software or the keypad. E.g., at some point in the future, I may add dynamic braking through the addition of an external braking resistor. The AC drive comes set up for this with dedicated terminals for this purpose, but, per the manual (Appendix B), first requires a change in the value of pr. 25 ("Over-voltage Stall Prevention"). Otherwise the drive will think the motor is stalling as it slows and will override the functionality of the braking resistor.

I'm not an electronics engineer, but I've studied the Delta user's manual and I do have a good friend who is and who knows his way around AC drives. I also have the advantage of having made parameter adjustments on my G0733 in the past to fine-tune it more to my liking (e.g., adding a braking resistor and customizing acceleration and deceleration rates). For G0766 owners who are sparkys or EEs, or have friends who are, making up the necessary wiring harness and performing this quick corrective fix should be fairly straightforward. It could save sending the whole headstock, or even the entire lathe, back to Grizzly. However, while your lathe is still in the warranty period, unless you are very confident about making your own adjustments, I recommend that you first speak to the Grizzly tech folks in Springfield. That said, the G0766 is still such a new product I'm not sure Grizzly tech support has run into much of this. Hopefully, it is turning out to be a very an infrequent condition. Otherwise our friends at Grizzly may want to reconsider locking the AC drive's keyboard in the production process to save avoidable warranty expenses.

It's my understanding that acoustic noise and electromagnetic noise induced by AC drives is not unusual across various types of machinery and different brands of VFDs. As some other SMC members have mentioned, I've heard of similar noise occurring in the Jet 1442 and the PM 3520B. Both of those lathes currently use the Delta Electronics VFD S-Series AC drive. In the S-Series drive, the pulse width modulation carrier frequency parameter is 2-03, and the S-Series manual states: "The carrier frequency can be increased when required to reduce motor noise." So I'm wondering if perhaps there are similar instances of high-pitched noise in some of those lathes that are as easily silenced as here with a simple parameter adjustment.

[hu lowery]

This doesn't seem relevant to anyone's issue in this thread but I want to add it here too in case someone in the future is chasing issues. My first 766 had a nasty whine. Turned out the belt just a hair too tight will make a high pitched whine. Loosening it just the tiniest bit to get a little more deflection when finger pressure is applied changed the belt on that one from a nasty high pitched whine to whisper quiet. A little whine from the VFD but not as high pitched and I assume normal, maybe just a hum if I am generous!

Eight big bowl blanks to rough tomorrow if I don't get sidetracked, I should be knee deep in shavings!

Hu

[Roger Chandler]

Great info David! I think your explanation was simple enough for me to grasp the concepts. My unit is pretty quiet, but when turning a lidded box yesterday, on the high belt position and at 1900+ rpms i noticed just a little of that acoustic noise [trill, chirp ?] that you mentioned.

I can say this......at this point, I could not be more pleased with the performance of my G0766. These sounds are normal in my estimation!

[Tommy Brennan]

I have owned the 766 now for a few months and have had every single issue listed with it on all the topics in this form about it and Moore. About a month ago I sent the headstock into Grizzly Tools repair multiple issues including the Mistry spacer set screws kept coming loose possible bad bearing run out terrible run out rethreading of the spindle on both sides with and will is and the headstock and so they replace the spindle with a new design which according to them was going to have threads all the way back to the shoulder. And fatter threads I just received yesterday after a month and some of the smaller issues like the Mistry spacer in the terrible sound from that in the set screws were correct it as well as the run out and they said they replaced both bearings in the spindle with the new updated spindle rod. Now the threads on the new rod are a little bit wider little bit shorter and it's angled in the front machined much better than the first one however the still only 6 1/2 threads and so my one-way Chuck my grizzly Chuck my barracuda to Chuck and my nova G2 Chuck will not screw all the way onto the shoulder and never have the only thing that does is the faceplate that came with the lace currently The runout has been fixed but as soon as I put a piece of wood on the leas I made a couple of passes and is this horrible clicking sound so I took the belt off to verify if it was coming from the top of the headstock on the bottom and of course while and turning the spindle the clicking is coming from inside the casting so obviously it's both or one of two of the bearings which were just replaced I haven't even been able to really use this tool in my opinion if you spend 500-1700 (tel:500-1700) or 8000 a tool should work. I am so frustrated with this lays someone please help because obviously grizzly can't ! Mine was manufactured April 2015, One question I'd really like answered is when you replace the bearings do you have to remove the snap ring first on the inside or does the Bering just pull straight out ?

[Hayes Rutherford]

Tommy, I just looked at the parts breakdown on the 0766. The bearings have to come off the hand wheel end so although it would be possible to get the the outermost bearing off without pulling the snap ring, there is no reason not to just pull the snap rings then use your method of choice. The outboard bearing on some lathes is a loose fit and slides off the shaft. If not, a slotted plate or bearing splitter and a press are used. Bearing splitter for the bearing against the indexing hub. I have also used a pinpoint flame on the inner race and tap the end of the shaft with a wood mallet. Assume any removed bearings will be toast. Replacement bearings are pressed back on to their exact locations with the appropriate size tube that will fit over the shaft and contact the inner race only(not the seals or outer race.)

I was surprised to see there are only two light duty bearings in that headstock.

[Roger Chandler]

Tommy, I just looked at the parts breakdown on the 0766. The bearings have to come off the hand wheel end so although it would be possible to get the the outermost bearing off without pulling the snap ring, there is no reason not to just pull the snap rings then use your method of choice. The outboard bearing on some lathes is a loose fit and slides off the shaft. If not, a slotted plate or bearing splitter and a press are used. Bearing splitter for the bearing against the indexing hub. I have also used a pinpoint flame on the inner race and tap the end of the shaft with a wood mallet. Assume any removed bearings will be toast. Replacement bearings are pressed back on to their exact locations with the appropriate size tube that will fit over the shaft and contact the inner race only(not the seals or outer race.)

I was surprised to see there are only two light duty bearings in that headstock.Hayes, the two spindle bearings are 6206zz double sealed bearings with a dynamic load rating of 19500 lbs. each. Static load rating of 13500 according to the information I found on the VBX bearings site. Not exactly wimpy bearings!

I think one of the phenomenon's we see on forums is that people post things they do not know about, or have minimal knowledge about, and at times they erroneously believe something is amiss.

You are an experienced turner, and that is not referring to you, but I cite the noise [some refer to it as chirp or whine] from the inverter. My particular G0766 unit has only gotten smoother and quieter as I have used it......some seemed a bit panicked when they first uncrated their lathes.....I think there is a normal break-in with all machines, and the inverter has to have time to adjust to the feedback it gets from the motor under usage. The first time or two the lathe is turned on will not likely yield its optimal performance in my experience. The same was true for my former G0698 lathe. There is excellent information earlier in this thread from David Roseman about changing parameters in the VFD for those whom this "noise" is bothersome.

Rough machining on the spindle that a few had is problematic, and likely was a QC issue at the factory. One thing that the customer servicing model that Grizzly uses, is that the end user is usually not technically qualified and trained to make some assessments in equipment operating parameters. I use myself as an example of this.....I am a pretty fair back yard mechanic.....I have rebuilt 3 engines and done many repairs from water pumps, starters, brakes, exhaust, tune-ups, timing chains, radiator replacement, etc, but some of the computer controlled stuff now requires programmers, software etc, so I must rely on trained technicians.

I have wired house circuits, done work inside panel boxes, wired my shop.....all up to code, but I am not a certified electrician. If I do have questions, I have a friend who is a certified Master Elecrician. Some technical aspects of electronic equipment, I am better off leaving to the experts.

I am just using your post as a means to comment in a general sense, and not taking issue with you or anyone else, so I hope you don't mind. I am just stating an observation I have seen from time to time, as discussions ensue around things related to lathes, not just the 0766. I had previously read comments about bearings, and had on a previous occasion done some research on this......I personally think the bearings in the 0766 are plenty strong for its intended use. It also has two other bearing sizes on the motor shaft, one if I recall is a 6205zz.

I have had some large pieces on my G0766,and the lathe has handled them well. It seems Grizzly is doing its best to resolve any issues for its customers......that is good. My personal feeling is the factory likely rushed to get the first orders out the door, and QC inspections were not as good as should have been. Hopefully, that is much better now! I want to see every owner of this lathe happy with its performance......it has great potential!

[Roger Chandler]

I have owned the 766 now for a few months and have had every single issue listed with it on all the topics in this form about it and Moore. About a month ago I sent the headstock into Grizzly Tools repair multiple issues including the Mistry spacer set screws kept coming loose possible bad bearing run out terrible run out rethreading of the spindle on both sides with and will is and the headstock and so they replace the spindle with a new design which according to them was going to have threads all the way back to the shoulder. And fatter threads I just received yesterday after a month and some of the smaller issues like the Mistry spacer in the terrible sound from that in the set screws were correct it as well as the run out and they said they replaced both bearings in the spindle with the new updated spindle rod. Now the threads on the new rod are a little bit wider little bit shorter and it's angled in the front machined much better than the first one however the still only 6 1/2 threads and so my one-way Chuck my grizzly Chuck my barracuda to Chuck and my nova G2 Chuck will not screw all the way onto the shoulder and never have the only thing that does is the faceplate that came with the lace currently The runout has been fixed but as soon as I put a piece of wood on the leas I made a couple of passes and is this horrible clicking sound so I took the belt off to verify if it was coming from the top of the headstock on the bottom and of course while and turning the spindle the clicking is coming from inside the casting so obviously it's both or one of two of the bearings which were just replaced I haven't even been able to really use this tool in my opinion if you spend 500-1700 (tel:500-1700) or 8000 a tool should work. I am so frustrated with this lays someone please help because obviously grizzly can't ! Mine was manufactured April 2015, One question I'd really like answered is when you replace the bearings do you have to remove the snap ring first on the inside or does the Bering just pull straight out ?
Tommy, did you file down the boss on your new spindle, or did they replace the original design with a spindle without a boss on it? I have heard nothing of a spindle re-design for the 0766. Keep us informed on this, if you will.....seems to me, that the logical step would be to get a replacement from the factory, but that may take some weeks to get it over here from the factory, so I wonder if tech support is trying something else as a substitute, in order to speed things up to try and make you happy? If that is the case, [which I have no way of knowing!] if it were me, I would want an original replacement, not a substitute that they think will be okay?!

[Doug McKnight]

Are the bearings shielded or sealed? I thought the "zz" designation meant shielded, but I could be wrong. I expect shielded is probably ok, but if there's casting sand knocking around then maybe it would be better to have sealed.

Doug

[Brice Rogers]

Are the bearings shielded or sealed? I thought the "zz" designation meant shielded, but I could be wrong. I expect shielded is probably ok, but if there's casting sand knocking around then maybe it would be better to have sealed.

Doug

Doug, you are correct, the bearings are shielded and not sealed. I wouldn't worry much about the casting sand but suspect that if there is an issue that it would be related to sawdust getting in over a period of time.

When I replace my bearings, I'm going to replace them with 6206-RS. RS stands for rubber seal.

[Brice Rogers]

Tommy et al,
I received a replacement spindle on Monday after waiting since around Oct 1. So, I am presuming that they sent me their current design rather than something that was manufactured last summer - - but that is a guess on my part. It looks basically the same as the original in most respects. I did not see any change in regards to a "new design with threads all the way back to the shoulder". You mentioned that "the threads on the new rod are a little bit wider little bit shorter". I mic'd the new threads and the major diameter are still around 1.229 (a bit undersized).
With respect to the spindle not screwing on, I suspect that Roger was correct in his question about whether you have filed down the shoulder (which is 1.260" or about 0.010 oversized). On my new spindle the grizzly faceplate won't thread all the way on, but that is due to the last thread being damaged during the machining process. When they turned the slot for the grub screw they messed up the last thread.331442

[Roger Chandler]

On the VBX Bearings website it is noted that double shielded bearings are sealed to keep contaminants out, and they are lubricated permanently. It uses the same zz rated as the original 6202zz bearings on my former G0698 for over 5 years, and our club now has that lathe with the same original bearings........with heavy usage, there has never been a problem with contamination, and believe me, that lathe has seen some serious dust!

The bearings on the 0766 are a lot bigger. I think some bearings have rubber seals and some are metal. I believe the zz are metal, but still keep out contaminants like dust.

[Hayes Rutherford]

Roger, first off, your bearing dynamic load is probably in Newtons, not lbs. So divide by 4.45 and get 4,382 lbs. While this still seems like a lot of weight, you know the forces an out of balance blank can exert.

In contrast, the 3520b has two 6207 bearings on the inboard side, the shaft is 35mm as compared to the 30mm of the grizzly. So by your reasoning could handle over twice the dynamic load of the Grizzly. This is the reason I thought the bearing arrangement looked light duty. Both of these lathes have a 6206 series on the outboard side.

Finally, industry standards designate 6000 series as extra light, 6200 series as light duty, and 6300 series as medium duty.

[David C. Roseman]

I have owned the 766 now for a few months and have had every single issue listed with it on all the topics in this form about it and Moore. About a month ago I sent the headstock into Grizzly Tools repair multiple issues including the Mistry spacer set screws kept coming loose possible bad bearing run out terrible run out rethreading of the spindle on both sides with and will is and the headstock and so they replace the spindle with a new design which according to them was going to have threads all the way back to the shoulder. And fatter threads I just received yesterday after a month and some of the smaller issues like the Mistry spacer in the terrible sound from that in the set screws were correct it as well as the run out and they said they replaced both bearings in the spindle with the new updated spindle rod. Now the threads on the new rod are a little bit wider little bit shorter and it's angled in the front machined much better than the first one however the still only 6 1/2 threads and so my one-way Chuck my grizzly Chuck my barracuda to Chuck and my nova G2 Chuck will not screw all the way onto the shoulder and never have the only thing that does is the faceplate that came with the lace currently The runout has been fixed but as soon as I put a piece of wood on the leas I made a couple of passes and is this horrible clicking sound so I took the belt off to verify if it was coming from the top of the headstock on the bottom and of course while and turning the spindle the clicking is coming from inside the casting so obviously it's both or one of two of the bearings which were just replaced I haven't even been able to really use this tool in my opinion if you spend 500-1700 (tel:500-1700) or 8000 a tool should work. I am so frustrated with this lays someone please help because obviously grizzly can't ! Mine was manufactured April 2015, One question I'd really like answered is when you replace the bearings do you have to remove the snap ring first on the inside or does the Bering just pull straight out ?


Tommy, welcome to the Sawmill Creek forum. I know there are quite a few people on here with the G0766 that are willing to try to help you. Are you able to post two or three photos of your new spindle (inboard end protruding over the bed)? That may help us better understand what you are saying about it. I'm asking because some of what you have written is very puzzling. I spoke to Grizzly Tech Support a few minutes ago out of curiosity, and they are unaware of a spindle redesign, much less one that would be threaded all the way to the spindle face. Threading all the way would leave no unthreaded portion for set screws (grub screws) in a faceplate or chuck to seat against! It would also eliminate the spindle boss (the shoulder formed at the spindle face), whose purpose is to help register faceplates and chucks as they tighten against the spindle face. The spindle boss on the G0766 (as well as the G0733) is machined to metric specifications and is a few thousandths of an inch too large to allow some aftermarket chuck inserts (e.g., Oneways, Novas) to tighten fully against the face. So, as Roger referenced above, you may only need to take a mill file and carefully hold it against the boss to reduce the diameter a few thousandths. There are some other posts on this on SMC. Check frequently as you go. It takes maybe 10 to 15 minutes. Perhaps what you heard from Tech Service was that Grizzly will be reducing the size of the boss to allow most chucks to "thread all the way up." I don't know if that's so, but it would be a good thing. That's very different than redesigning the spindle to "have threads all the way back to the shoulder").

In any event, if you can post some photos, that will help us on this issue.

As for the horrible clicking sound you're reporting in your new headstock, I'm really wondering if the replacement headstock Grizzly sent you still has that same "mystery spacer" that you read about in an earlier thread. That spacer is not shown on any parts list or diagram, and evidently was used at the factory to register the positioning of the spindle pulley. If it is not sandwiched tightly, it can cause an awful racket that mimics a bad bearing. The easy solution is simply to remove it altogether, as I and others have, as it has no functional purpose in the assembled lathe.

If Grizzly indeed put new bearings in your replacement headstock, I think it is unlikely in the extreme that the noise you are now hearing is a bearing. Also, check the positioning of the bracket that holds the electronic sensor that reads the revolutions of the rare-earth button magnets in the spindle pulley and sends the info to the digital speed display. I don't think that's the problem, but if the bracket or sending unit contacts the pulley it can certainly cause a click.

If you would like to talk about any of this in real time, send me a PM with your phone number or email and I will be happy to contact you offline to discuss. Also, your posting info doesn't say where you are located. There may be another G0766 owner in your area with more experience who could actually have a look at your lathe with you. Grizzly has sold hundreds of these lathes. In just our local club, nine people have bought them so far. Worst case, you are still within warranty and I'm sure Grizzly would even replace the entire lathe at this point, if that proves necessary.

[Brice Rogers]

On the VBX Bearings website it is noted that double shielded bearings are sealed to keep contaminants out, and they are lubricated permanently. It uses the same zz rated as the original 6202zz bearings on my former G0698 for over 5 years, and our club now has that lathe with the same original bearings........with heavy usage, there has never been a problem with contamination, and believe me, that lathe has seen some serious dust!

The bearings on the 0766 are a lot bigger. I think some bearings have rubber seals and some are metal. I believe the zz are metal, but still keep out contaminants like dust.

Roger, I agree with the bulk of your post. Both zz and RS are made to keep out dust and contaminants.

But in your comment, "On the VBX Bearings website it is noted that double shielded bearings are sealed to keep contaminants out" is not 100% correct. The zz is shielded and the rs is sealed. The key word is "sealed". Yes, I know - - that is an issue of semantics and perhaps I'm picking "nits" here ;). On the VBX website they refer to zz as "each 6206ZZ bearing is closed with 2 Metal Shields" and the RS as "Closures: Rubber Sealed". In practice both closures would probably do fine.

The difference between the two is that with the shields, there is a paper-thin clearance or gap between the metal shield and the inner race. (I don't know exactly how thin it is, but it has got to be pretty small). It is a small enough clearance that it is effective in keeping the dust and particles out. The RS or rubber seals actually have a rubber seal in contact with both the inner and outer races. So there is no gap whatsoever. But, this causes a little drag and friction and also limits the upper speed and temperature that the seals can take.

So, upon doing more research, I think that I would probably replace (if I have to) the 6206zz with another set of shielded bearings. The RS bearings are sealed, but their upper temp range is less. The zz shields will adequately keep out contaminants and can withstand higher spindle speeds.

[Roger Chandler]

Roger, first off, your bearing dynamic load is probably in Newtons, not lbs. So divide by 4.45 and get 4,382 lbs. While this still seems like a lot of weight, you know the forces an out of balance blank can exert.

In contrast, the 3520b has two 6207 bearings on the inboard side, the shaft is 35mm as compared to the 30mm of the grizzly. So by your reasoning could handle over twice the dynamic load of the Grizzly. This is the reason I thought the bearing arrangement looked light duty. Both of these lathes have a 6206 series on the outboard side.

Finally, industry standards designate 6000 series as extra light, 6200 series as light duty, and 6300 series as medium duty.Hayes....thanks much for this information. I appreciate the education! :)
If the 6200 series bearings are considered light duty, and the 3520b uses two of them, I realize that is twice the load capability as one bearing.....but they are still "light duty" correct? My question then becomes is there a heavy duty bearing.....say a 6500[?] series that has the same dimensions of the 6206 zz and would make it possible to increase the load capability? I might have to do some research on this, and get back to the subject. Perhaps I will talk with some experts at VBX.

[Hayes Rutherford]

Roger, I don't think there is a 6500 series and only familiar with 6300 series(medium duty used by Robust)but I wouldn't worry. We are talking wood lathes not rock crushers. The last number in the series indicates the shaft size: 6207 is 35mm, 6206 is 30 mm and I suspect you multiply that number by 5 to get the size in mm. Something else that doesn't seem logical is that these bearings are c3 which means "loose fit"

Something else you mentioned was the bearings in your former G0698 were 6202 and the the G0766 had much larger ones. According to Grizzly's parts manual, they both use the same 6206zz bearings. So if they work in the 0766, they will surly work as well in the G0698. You might check that out, it could be a misprint.

[Roger Chandler]

Roger, I don't think there is a 6500 series and only familiar with 6300 series(medium duty used by Robust)but I wouldn't worry. We are talking wood lathes not rock crushers. The last number in the series indicates the shaft size: 6207 is 35mm, 6206 is 30 mm and I suspect you multiply that number by 5 to get the size in mm. Something else that doesn't seem logical is that these bearings are c3 which means "loose fit"

Something else you mentioned was the bearings in your former G0698 were 6202 and the the G0766 had much larger ones. According to Grizzly's parts manual, they both use the same 6206zz bearings. So if they work in the 0766, they will surly work as well in the G0698. You might check that out, it could be a misprint.

That is correct, Hayes......seems my memory was faulty a bit.:o..[it has been several years since I got those extra bearings for the 0698]. I did speak with someone at a bearing distributor, and the bearing size [outer dimension & inner bore dimension] is what determines the load a bearing can handle. The dimensions for a 6206 and a 6906 are different, so the dimensions of the race machined into the spindle housing on the headstock determines the actual bearing that will fit , of course....but the dimensions and load rating are fixed, and the material that the balls and race are made from are all pretty much the same, and the rating from brand to brand is as well.

What I was hoping was to be able to buy a more heavy duty bearing in the same size, but it looks as if that is not a possibility........oh well! :(

[Doug Ladendorf]

What I was hoping was to be able to buy a more heavy duty bearing in the same size, but it looks as if that is not a possibility........oh well! :(

Roger, you shouldn't need a more "heavy duty" bearing, but you CAN buy a better quality bearing, and I think that exercise would provide a great additional data point to the other information you have offered already on the G0766. I have replaced bearings with Nachi brand, made in Japan, which I have found to be very good. Many of us OWWMers use Accurate Bearing ( http://accuratebearing.com speak to Lynn) for good support and reasonable prices.

Doug

[Roger Chandler]

Roger, you shouldn't need a more "heavy duty" bearing, but you CAN buy a better quality bearing, and I think that exercise would provide a great additional data point to the other information you have offered already on the G0766. I have replaced bearings with Nachi brand, made in Japan, which I have found to be very good. Many of us OWWMers use Accurate Bearing ( http://accuratebearing.com speak to Lynn) for good support and reasonable prices.

DougThanks Doug.....my current bearings are just fine, but I do tend to do things of a preemptive nature when it comes to maintenance on my equipment. I will probably get a couple of premium bearings and have them on hand for future needs if they arise.