Tight screw

I have an ML7R and the topslide has a tight leadscrew, Ive had it all apart and can see no obvious reason why (burrs, nicks, bends etc) has anybody else had the same problem and what resolution did you find to work.

Paul

Reply to
wingnut
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The feedscrew on my ML7 top slide engages in two threads, one being the thread tapped into the iron base section, the other being tapped into a loose brass block behind the feed nut. The brass block, which strangely is not shown in the Myford manual, has two fixing screws and two jacking screws that I assume are to enable any slack or backlash to be taken up. I found it necessary to adjust these four screws to free off the tight feed screw. The way I did it was to loosen the jacking screws, tighten the fixing screws and then gradually loosen them until the feedscrew was free enough, then tighten the jacking screws to lock the block in position.

Cliff Coggin.

Reply to
Cliff Coggin

Could it not be shown because a previous owner has bodged it? The Myford top slide has a screw similar to the cross slide screw that screws into a mazak but held in by two cheese head screws.

The base section has a hole for the feed nut to locate, no tapped holes.

To get back to the original question have you tried running the nut down the screw on it's own to check that it's free. This way it will check whether you have a screw / nut problem or a slide / gib problem.

-- Regards,

John Stevenson Nottingham, England.

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Reply to
John Stevenson

I've had issue with the leadscrew bearing surface at the handle. Balancing a snug fit, against one that will allow fine swarf to get in was a problem, and it did make the leadscrew feel tight in places, if the nut does turn out to be OK. Look at the leadscrew bearing surfaces.

Joules

Reply to
Joules

I agree with John that Cliff's top slide has been modified by an enterprising previous owner, although why one would want a backlash free top slide is beyond my comprehension.

On the question of Paul's stiff screw (no smutty joke intended), and at the risk of stating the obvious, I presume that the bearing bracket screw have been left loose until the feed screw has been fully screwed in to ensure the alignment of the bracket before the fixing screws are tightened. Assuming of course that John's test shows the nut to be free running on the screw.

Regards Brian

Reply to
brian

Paul, forget everything I wrote above as it actually refers to a Pultra lathe. Sorry if I misled you, but I have done the same job on both the Myford and the Pultra recently, and I seem to have got the two muddled up in my memory. What the Americans call a senior moment!

Cliff.

Reply to
Cliff Coggin

Hi Cliff My configuration seems different from yous with just a mazak bushing held in place with 2 cheese head screws. Thanks for your input.

Regards

Paul

Reply to
wingnut

Hi John no I have not tried that, should give me a better insight as to where things are going wrong.

Cheers

Paul

Reply to
wingnut

Hi John no I have not tried that, should give me a better insight as to where things are going wrong.

Cheers

Paul

Reply to
wingnut

Hi Brian, nope I haven't done that either, I acquired the machine a few weeks ago and I am in the process of cleaning it down and swapping a few bits over when I came across this tight leadscrew. I am going to take the nut off and the leadscrew out so I can start identifying what might be amiss I will certainly bear in mind leaving things slack untill I get some form of alignment, thanks for your input.

Paul

Reply to
wingnut

Hi Cliff, no problem, I have actually moved on from Senior to C.R.A.F.T moments, Can't Remember, A, Flaming, Thing, well something like that anyway????

Cheers

Paul

Reply to
wingnut

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