Having finally picked up my cheap-as-chips Myford ML7 about 2 weeks ago I got it cleaned up enough to try a few cuts this week and was reasonably pleased that it actually cut quite well and ran pretty smoothly despite my disapointment at its initial appearance.
It had been stood under a tarpaulin for the past 15 years, unused apart from turning the occasional broom handle down, but the tarpaulin itself was under a leaky roof. Luckily the bed and slides were untouched (helped by the 15 year old oils and greases dried into them I am sure) but I had to use a paint scraper to lift the 1/2"+ layer of rust sitting in the tray.
No doubt this was sacrifical swarf cunningly anointed with holy suds and left in situ for just such an occurrence. I digress.
Although the main spindle and bearings seem fine, no obvious play anywhere and the oilers let a nice flood of hydraulic oil through to pool on the tray, the same can't be said of the leadscrew. Neglect (probably) or blocked oil nipples (equally probable) mean that I've got
0=2E006"- 0.008" of uneven wear on both bearing ends of the leadscrew where they run in the oilite bushes. Coupled with a dodgy tooth somewhere in the geartrain I now have a playful leadscrew that likes to do a little hop, skip, and jump every now and then.The bushes are hardly worn at all.Myford list a new 5/8" leadscrew at =A3136 odd which is actually quite reasonable given the work involved to make one, but of course thats far more than the scrounge-and-borrow attitude wants to pay if avoidable:) So the options would appear to be either turn/grind the bearing surface down locally and make half-shell phospher bronze bearings to fit this (probably not a good idea..) or get the area spray welded and then turn/re-grind it. Having finally got on to the point of my post, has anyone done this on something similar or knows a man who can? John S perhaps.....? Advice, comments, and brickbats welcomed.
Peter