Cross slide adjustment Myford ML7

How do you adjust the top slide on an ML7? Mine seems to lift up and down slightly, so simply adjusting the gib screws wouldn't eradicate this.

Have you tried adjusting the gib screws as there are no other adjustments?

If, when set snugly, it still moves then I suggest that the dimples in the gib strip are worn or the tips of the screws are worn.

Remove the screws holding the leadscrew assembly and swing under, thus leaving just the topslide, it should be an even snug fit when pushed to and fro.

The top slide is carried on the V (sideways) on each side. The lower side of each V is horizontal. The gib screws press on the gib, effectively pulling the slide over to their side and tightening the slide into the opposite V. At the same time the gib presses on the top of its own V forcing the base of the slide into contact with the lower side of the V. As long as this is what you have, it should always be possible to 'overtighten' the gib screws and lock the top slide down onto the horizontal surfaces on both sides.

So, it seems that you may have your gib screws mis-assembled, not locating in their cut-outs (or dimples). Or possibly a home-made gib strip which is not big enough?

Alternatively, it may be that the up-&-down movement you are feeling is not the top slide itself but below it. Perhaps the saddle on the bed, or the cross slide?

Hope this helps

Regards, Tim

Sussed it. It was a combination of both the handle screw thread play and gib screws. I undid the lock nut on the topslide handle wheel, adjusted and and retightened it, then adjusted the gib grub screws. Thanks for the suggestions guys.

gibs will be the bane of your existence, however, if you manage to make atleast 1 modification, i would ditch the allen key and go for a knurled wheel adjustment (with possibly 4 shallow holes around the wheel so that you can tighten them with a bar if the need ever arose) it saves alot of hassle i've heard. Instead, you could do small lock handles as an alternative but this often needs alot of room to work.

Another popular modification to the myford crosslide is the feed nut itself, for the leadscrew that is, To split the nut 3/4 depth and a cross bolt so you can turn it into a pinch bolt.

Michael W

Edited By Michael Walters on 01/05/2016 21:14:59

Once correctly set up it should not be necessary to continually adjust the gib screw. One important point, remember that the top slide has to be lubricated and kept clean.

FWIW I just did the G. H. Thomas gib-dowel mod to both the top-slide and cross-slide on my ML7 (he describes it just for the top-slide) and I must say it has really improved it. I can now adjust the gibs to take out all noticeable play while still leaving a free movement.

Well worth doing in my opinion.

Bandersnatch, the GH Thomas mod sounds interesting. Where would I find the recipe?

George

It's in one of his books "The Model Engineers Workshop Manual" (the red-cover book).