Member postings for Alan Thomas 7

Thanks Guys for all your thoughts and advice. I am sure scraping would be the 'professional' way to go but i don't have a scraper small enough to do the job and I am disinclined to practice on bearings that are no longer available. I just checked and a replacement spindle and new bronze bearings (have to replace spindle with new bronze bearings) would be more than I paid for the lathe.This and the fact that the bearings are not worn lead me to additional shimming.

I took out the spindle , cleaned all traces of oil then reassembled with the original shims but left both caps loose and working on one end at a time inserted feeler gauges either side of the cap in addition to the shims already in place. You can lay the feeler along the entire length of the cap outboard of the screws. I started with 0.010" this was very loose, jumped to 5 thou then reduced by 1 thou at a time, tightening down on each step and measuring the play with a DTI by gently levering the chuck end of the spindle with a piece of wood up and also side to side. I got down to a 3 thou feeler either side on the chuck end cap and a 2 thou feelers on the other end. With these feelers in place I could just turn the spindle by the chuck thread with my fingers.

'Steve Vine 1' on this forum sent me a msg suggesting using kitchen foil to provide the extra shimming. What a great idea I tried and you can punch the hole with a paper hole punch and cut the stuff with scissors. measured the foil we had and it is near as damm it 1 thou thick.

Made up the shims required, fitted, tightened down the caps, tested for play with the DTI and all is good, job done. All oiled up and I do have a job that will require running for some time so I will monitor if bearing gets warm. Too warm and I'll add another 1 thou foil shim.

Anyone want to buy a genuine unused pack of Myford laminated shims cheap?

Thanks again guys - Alan

Edited By Alan Thomas 7 on 12/01/2020 11:00:10

I have searched the forum and it is obvious there are people with knowledge on this topic but none of the old posts covers the point I want to raise.

I have an early (1948) ML7 with history unknown which seems to have very little wear and no damage, I have been using it for a few projects over the last 5 years but recently realised the headstock bearing caps screws were loose. I loosely tightened the caps and the spindle locked up.

I removed the caps, pulled out the spindle and found both spindle and bearing were in 'as new' condition. I measured the shims, they were the laminated type, all to be 17thou .

Thinking someone had removed too many laminates I ordered new shim packs from Myford and were surprised to find that the new ones were also 17thou. I then replaced the bearing caps without spindle and shims and tightened the caps until the white metal bearing halves were touching each other and measured the gap where the shims would be, it was 16 thou. So even with new shim packs I was only going to 'space' the bearing by 1 thou at the most?

The bearing caps showed no evidence of filing of any post manufacture machining so what’s happening?

I think at some time in the recent past it was fitted with new spindle, shim packs and white metal bearings (before they became unavailable) and the last owner found the spindle locked without any of the shims being torn off so he simply left the screws loose.

Anyone else had this problem, the only solution I can see is to just add the new shims on top of the existing then rip off until correct adjustment.

- Alan