PDA

View Full Version : New Lathe



tom lucas
02-02-2019, 3:34 PM
I was hoping to someday get a Powermatic or Robust. But, I "need" one now and can't afford those. So, it's the ol' "best value" brand: Grizzly. Pretty nice so far.

402580402581

Tim Passmore
02-02-2019, 3:51 PM
Congratulations Tom. I've been very pleased with mine.

Roger Chandler
02-02-2019, 3:52 PM
Congrats on your Grizzly 22x42 lathe, Tom. That is a nice setup! Trust me, as one who has turned on numerous PM 3520b's, the performance on your lathe will surprise you! The G0766 has more swing, more distance between centers, more horsepower, more advanced inverter than the 3520b, and will do anything the 3520b can do as far a projects, and some the 3520b might not be able to do because of the bigger swing, so as one who thinks the PM3520b is a fine lathe, having a good bit of experience on that model, and own the G0766 myself..........believe me...you did good!

tom lucas
02-02-2019, 4:38 PM
I put a big bowl blank on it that was slightly not true. Turned it up to 1000 rpms and got quite a bit of vibration. I'm on a wooden floor over a basement. I think it's largely the floor. Would sand help, or just be a waste of time and money? I'm not bolted to the floor.

Perry Hilbert Jr
02-02-2019, 4:55 PM
impressive. I too "jones" after a better lathe, but frankly, so far the old Delta Rockwell, high school shop lathe has done everything asked of it and more. Since I have not tried bowls over 12 inches, a larger one has not been a desire

Tim Passmore
02-02-2019, 5:11 PM
I built a ballast box from my packing materials and put about 200 pounds of sand in it.

tom lucas
02-02-2019, 5:24 PM
I built a balist box from my packing materials and put about 200 pounds of sand in it.

I'm planning the same thing, but not sure it'll help if the floor is moving.

Richard Coers
02-02-2019, 6:22 PM
I put a big bowl blank on it that was slightly not true. Turned it up to 1000 rpms and got quite a bit of vibration. I'm on a wooden floor over a basement. I think it's largely the floor. Would sand help, or just be a waste of time and money? I'm not bolted to the floor.

Depending on what you consider a big bowl blank, 1000rpm is a ton when starting out. Good way to launch something! Most start at 300-400 rpm.

tom lucas
02-02-2019, 6:51 PM
It's 15" by about 6" thick mounted on a faceplate. Outside already mostly cut on my old lathe, before it died. Spinning at 1000 to burnish in some O.B. Shine juice. No cutting going on.

Roger Chandler
02-02-2019, 7:01 PM
Wooden floors will always give you some vibration.........unless they are reinforced with heavy beams. I have wooden floors in my shop building, and that is why I turn out of balance at slower speeds, and usually don't turn bowl blanks at much more than 850-950 rpm. I have turned some at higher speeds, but when you get to upper speeds you induce flexing in the sidewalls, and defeat your ability to get an even cut. Of course you can use a bowl steady which helps, but it will only do so much.....find the sweet spot on rpm's with each piece. If you pay close attention you can get it dialed in to the best cut for the wall thickness and type of wood being used.

tom lucas
02-02-2019, 7:07 PM
Thanks Roger. That is why I hesitate to add sand ballast. I'm not sure it'll help. The floor is well supported with steel i-beams at 11' on centers. But I'm at the wall end, spanning out about 6' (near weakest point) on the joists.

Alex Zeller
02-02-2019, 7:54 PM
I'm very happy my G0766. I don't see myself outgrowing it any time soon (that was my biggest fear). I usually just start out with the speed that is just below vibrating with pieces that are out of balance. Usually anywhere around 200 ~ 300 rpm and slowly speed it up as the project gets more in balance. I have my head stock sitting over the left leg. I'm no expert but I assumed that the middle of the bed isn't going to be as stiff.

Before I moved it into it's final spot I didn't level it that well. I just used a standard bubble level. After moving it I used a machinist level and spent lots of time going back and forth on each leg. It'll surprise you how much the bed will twist while doing. If I was going to add a ballast box I think I would make it out of 12" pipe with steel plates welded on each end that I could bolt to each leg. A bung welded to the top would allow it to be filled with water. Between the pipe and water it should weigh around 250 lbs. If I feel like it I could run supports to the bed to help stiffen it up. The bed has several braces cast into it to connect the ways together that would be easy to clamp onto. I'm not sure it's needed though but, if you haven't realized, I plan on keeping the G0766 for a very long time.

About the only thing that I've upgraded is the tool rest (personal taste) and I put a larger potentiometer in it for speed control simply because I found one that would work fine as a replacement. The factory solders it in place so I swapped it out with quick disconnects so if it ever does go bad it's a 5 minute job (or less) to replace. The factory potentiometer was working just fine and I didn't need to do it I just wanted to.