Here is a homemade black acetal washer, shown in place on my leadscrew:
Remove the handwheel and the key (you can see the keyway slot just above, may require pliers to get the key out of there), and assuming you have already removed the front black accordion cover, you just remove the two socket head bolts that hold the front "Y-axis leadscrew retainer" in place and off she comes.
You can see the LS shoulder just behind the new washer shown above - the Y-axis leadscrew is left hand threaded, so cranking the handwheel counterclockwise to move the table towards the back, causes the leadscrew (equal and opposite reaction) to move towards the front. That shoulder in the leadscrew wears directly on what LMS calls the 1476 Retainer, Y-Axis Leadscrew.
http://lmscnc.com/1476
I never had a problem until I forced the hand wheel a bit further than it wanted to go, just trying to finish what I was working on. This caused that shoulder in the leadscrew to really bear into the retainer hard, and afterwards it felt really rough to turn when moving the table towards the back. Lightly wet sanding the LS shoulder smooth and placing the washer as you as you see above got it turning smoother than before there was ever a problem. The little picture of the y-axis leadscrew retainer above, conveniently shows the face of the retainer that the leadscrew shoulder wears against when cranking the the hand wheel counter clockwise (Remember it's left hand thread).
Since the retainer and dial with it's odd 62 and 1/2 marks already has a built in metal ring between the dial and the retainer - and I didn't like the gap between the dial and retainer created by putting a washer in there between them- I only used the one washer shown above. Works for me, but YMMV.
No hammering or banging on anything was involved in doing the simple thrust washer mod. Although in my case I used my mini-lathe to make the washer. As always, you need to be vary careful not to lose the little spring clip that fits inside the dial if you decide to take the dial apart...!
Cheers,
John Z.
On 1/28/2012 1:07 PM, chucketn wrote:
I know this is an old thread, but I just got a pair of the thrust washers from David Clarke. I'm trying to install them in a cold garage. I can't seem to get the bearing housing off the Y axis lead screw. It should just pull off, right? The hand wheel came off o.k., and I will replace the two lock nits with a nylock nut as advised in David's instructions.
Chuck in E. TN