Shopsmith Forums

Can someone tell me if the Dual Bearing Drive System is a worth while upgrade for my 500. I just have a single Bearing now and I use the Shopsmith mainly for a lathe.

Rich

rwilabee wrote:Can someone tell me if the Dual Bearing Drive System is a worth while upgrade for my 500. I just have a single Bearing now and I use the Shopsmith mainly for a lathe.

Rich

What are you turning on the lathe?

Are you having any problems with the current quill?

IMHO If it ain't broke, do not 'fix' it!

Now if you are intending to turn some heavy bowls etc., then it might be a good idea.

Just because I like to overbuild certain things, I had Skip Campbell from MKCtools.com build me a 2 bearing quill for my 56 Greenie restoration. I like it.
I'm leaving the gilmer drive, and just cleaned and went through the clutches.
my 32 cents worth.

Yes I'm going to be turning some 10 to 12 inch x 4" thick wood that some of it will still have moisture in it making it fairly heavy. I tried to turn a piece of 10 inch x 4" thick (Big Leaft Maple Burl) which I cut round on the band saw and then attached the face plate to it. I then put a live center on the tail stock and trued up the wood, but when I removed the live center to I could turn internal dove tail tenon for my chuck the wood was vibrating terribly. It was fine until I removed the tail stock with the live center. I not sure what I did wrong or if that is pushing the limits of the lathe for a piece that size with about 14% moisture. I was running the lathe at about 1000 RPM. It was still vibrating terribly when I slowed it down lower.

Rich

rwilabee wrote:Yes I'm going to be turning some 10 to 12 inch x 4" thick wood that some of it will still have moisture in it making it fairly heavy. I tried to turn a piece of 10 inch x 4" thick (Big Leaft Maple Burl) which I cut round on the band saw and then attached the face plate to it. I then put a live center on the tail stock and trued up the wood, but when I removed the live center to I could turn internal dove tail tenon for my chuck the wood was vibrating terribly. It was fine until I removed the tail stock with the live center. I not sure what I did wrong or if that is pushing the limits of the lathe for a piece that size with about 14% moisture. I was running the lathe at about 1000 RPM. It was still vibrating terribly when I slowed it down lower.

Rich

Excess speed for the workpiece, not quill runout. Wet burl does not 'balance' well. You may need to weight the ss down.

I started offering double bearing Poly-V quills many years ago. The Gilmer drive system never offered a double bearing quill. Starting this spring, I found machinest who could machine to a .001 accuracy. We investigated where to locate the second bearing: directly between the front bearing, use a 1mm space to seprate the 2 bearings and add a bearing 2: from the splined emd (only Poly-V quills). After intensive testing we found the 2 bearings with the 11mm spacer has less deflection under heavy loads. I offer a 1 year warrenty on the douldle bearing quills that I machine. I have a hand built headstock quill tester to determine quill and bandsaw wheel runout when operating. I use a higher grade bearing in the quills. These quills are listed on Ebay most of the time. iPlease contact me if interested.

JPG40504 wrote:Excess speed for the workpiece, not quill runout. Wet burl does not 'balance' well. You may need to weight the ss down.

Does the Excess speed mean that I was trying to turn to fast at 1000 or not fast enough. It sure surprised me that it was fine between the head and tail stock until I removed the tail stock.

Rich

rwilabee wrote:Does the Excess speed mean that I was trying to turn to fast at 1000 or not fast enough. It sure surprised me that it was fine between the head and tail stock until I removed the tail stock.

Rich

Generally until something is round and/or balanced slower speed is better. For large turning I used to use the speed reducer until I got my PowerPro.

I did not realize it until I tried to lift my machine 4" to add washers to the casters but all the stuff I keep on the accessory shelf is very heavy and really adds to the stability while turning, I have never had to add extra weight even when turning a 1/2 log to create a natural edge bowl.

get the spped lower either by turning the speed control to the lowest setting or try to get a speed reducer.
Bill V

'Excess speed' means too fast!;)

'Insufficient speed' means too slow.

When turning an imbalanced object, inertia of the revolving part(constantly changing direction) will try to move the machine that is rotating it. Too fast and the object and machine vibrates. A bit slower and the object and machine jump around. Real slow and the object and machine remain calm(er).

The tailstock helps tame all that inertia.