ml7 tri leva cross slide screw ?

[BASS 666Participant @bass666]

[BASS 666Participant @bass666]

guys is the tri leva cross slide nut the same as the rest of the ml7s ? if so where do i buy one ?

i have looked everywhere even on the Myford site but they don't sell them as a single unit and there are some on ebay but it's the part number i'm worried about ..

there is a very small bit of play in the cross slide ( about 20 thou ) but the screw looks good the whole length so i'm gonna try a new nut if i can get one …

thanks guys …

[HopperParticipant @hopper]

I would expect it to be the same as standard ML7 but have no experience of the TriLeva in person.

Myford stocks them periodically but they sell out fairly quickly. Other sellers on eBay have them. No idea of quality though.

Make sure the slack is not in the adjustment where the handle and dial screw on to the spindle. It can be fiddly to get set up just right, and is often the source of most play.

Anyhow, slack in the nut does not really affect lathe performance. It will still cut true to size regardless of slack there. You just have to remember if you are winding in and want to go back a thou or two, you have to go back past the slack and then wind back in to the number on the dial you want. Even with a new nut there will be some slack there and you always have to do this.

[BASS 666Participant @bass666]

Posted by Hopper on 15/04/2022 13:11:10:

I would expect it to be the same as standard ML7 but have no experience of the TriLeva in person.

Myford stocks them periodically but they sell out fairly quickly. Other sellers on eBay have them. No idea of quality though.

Make sure the slack is not in the adjustment where the handle and dial screw on to the spindle. It can be fiddly to get set up just right, and is often the source of most play.

Anyhow, slack in the nut does not really affect lathe performance. It will still cut true to size regardless of slack there. You just have to remember if you are winding in and want to go back a thou or two, you have to go back past the slack and then wind back in to the number on the dial you want. Even with a new nut there will be some slack there and you always have to do this.

i have the adjustment where the handle and dial screw on the spindle just nice not too tight .. the lathe works perfect and i do adjust for the slack but i do think the nut is well worn so if i can get one and do the thrust bearing mod then it might help it a fair bit …

[SillyOldDufferModerator @sillyoldduffer]

Posted by Hopper on 15/04/2022 13:11:10:

…

Anyhow, slack in the nut does not really affect lathe performance.

…

+1 to that, at least not until the wear is severe.

Before spending money and after checking Hopper's handle possibility:

• Check the screw with a micrometer, the Mk 1 eyeball isn't much good at detecting wear spread gradually along a screw. Check the diameter across lands at the ends and in the middle where most of the action takes place. Better to buy a new nut and screw as a pair if the screw is worn.
• I don't know (yet!) if Myford nuts can be adjusted to take up slack. Mini-lathes have screws allowing the nut block to be tilted so even worn threads can be adjusted to minimise backlash. Another type has a slot cut across the block at one end allowing a screw to crush a few threads again to minimise backlash. The Myford nuts on the web don't seem to have either feature, but possibly they're tilted by the two fixing nuts

In general, I'd advise against constantly fiddling to reduce backlash. As it's always present to some degree, best to learn to eliminate it by always backing far enough away so the screw and nut will re-engage fully before trusting the dial. Or if that's too hard, fit a DRO! But the chief objection to frequently reducing backlash is it greatly increases wear and tear on both nut and screw, uselessly knackering them long before their time. Fusspots aren't good at doing the right level of maintenance and are strongly inclined to break things by fixing them unnecessarily!

Dave

[Jon LawesParticipant @jonlawes51698]

Quite a bit of backlash isn't unusual, but its probably not the nut.

As others have done, on my ML7 I bored out the hole that the shaft goes into and fitted a 1/4 x 3/8 x 1/8 sealed bearing, with an NTA411 bearing either side (a needle roller bearing with washers, two of, part number NTA411). The removed a vast quantity of the backlash.

[BASS 666Participant @bass666]

i measured the screw and it's nearly perfect maybe someone changed it ? if i hold just the screw and move it in and out of the nut i can get about 40 thou and when the screw is attached to the lathe again and i move the cross slide i get about 20 thou movement …

i have sent for the thrust washers and maybe do what jon lawes did and send for a bearing as well ..

i have used the lathe quite a few times now and made a few threading tools as well as some stuff for the motorbikes and i am used to allowing for the slack but i thought if i could get rid of it then it would be a bonus …

[bernard towersParticipant @bernardtowers37738]

Unfortunately Bass you can get rid of it but it will reappear a short while later. The thrust bearing mod mentioned earlier is a good start as when fitted the play you then have is definitely screw or nut. But as you usually travel in one direction is it really that much of a problem?

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