Chris its plenty curable.
There’s the expensive solutions like fitting ball screws. Deluxe, quality result, best if you have a DRO, because you may end up with a funny amount of thous per turn. (or .01s of a mm)
Step 1 is to check the handwheel/feedscrew clamp at the x slide bracket. Make sure that’s adjusted properly. If you can, fit roller thrusts. Very cheap very easy, which is why I have never got round to doing it on the Myford (but it is properly adjusted!) All the Chinese kit and the Dore Westbury has them. Worth doing.
Step 2. The easy DIY fix is to knock up a tap in silver steel. ie thread cut and then gash the flutes. (or try Tracy tools) Best if it matches the threads very closely, bearing in mind the tap cuts the spaces. But if they don’t well its not a disaster. What you are going to make is a feedscrew nut extension, secure the two together with a couple of allen bolts (or even a bit of tube and Loctite retainer though that’s not as great on bronze feedscrew nuts as it is on steel) Pop a few shims in between the old nut and the new bit. Backlash gone.
If it bothers you. If your slides are properly adjusted, and you always come back beyond ie you always physically drive the slide into position, then its not really a problem, except possibly on an interrupted cut. (But hten you just lock the slide)
You may find a new feedscrew and nut is pretty economical too. Quality has improved a lot.
If you need a tool ground up, let me know and the Quorn will oblige.Won’t take more than a few minutes. You’ll have to set it in a toolholder at the helix angle, or it’ll rub while you are screwcutting, (sorry Granny) but apart from that, cutting acme threads is no more difficult than any other. Any of the screwcutting books will tell you how to work out the helix angle for your thread. That allows a setting flat to be ground, and the correct offset to be applied on the Quorn (in rotation) The operator just puts the flat up against a setsquare.
Edited By meyrick griffith-jones on 29/08/2009 22:32:02
Edited By meyrick griffith-jones on 29/08/2009 22:35:10