Leveling and fixing a Myford lathe

This topic has 6 replies, 6 voices, and was last updated 23 August 2016 at 18:11 by Ajohnw.

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23 August 2016 at 14:18 #251985
choochoo_baloo
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@choochoo_baloo
Dear all,

After flicking through an original Myford ML7 manual to accompany my secondhand ML7, I am unsure what I need to do to properly attach the lathe bed to the raising blocks.

I have read and understand the procedure(s) for ensuring dead level lathe bed from the meal, but I need to have lock down nuts available to complete the procedure. As seen in the attached images, both blocks have nuts (which are truly stuck in place!) between the bed and raiser block surfaces. However no additional nuts are available to lock it down, and I fear there's insufficient thread protruding to attach nuts in a couple of places (second image).

Please can someone explain how to arrange the bits (including buying additional nuts if required) to (a) properly complete the levelling procedure and (b) then permanently fix the bed in place.
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23 August 2016 at 14:18 #8258
choochoo_baloo
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@choochoo_baloo
23 August 2016 at 14:47 #251989
Martin Kyte
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@martinkyte99762
The 'nuts' below the feet as you have described are for adjusting the height of each foot support.They are actually part of the jacking screws Unscrew to raise and screw in to lower. All you need are 4 washers and 4 nuts to go on the top. Does the lathe rock when you pull it about. If so the studs/jacking screws need adjusting until each foot is completely supported. There should be the same thread length on all four screws so I suspect the 'short' one as shown is actually not in contact with the bottom of the foot. It's handy if you have a thin open ended spanner to adjust the jacking screws from under the feet without having to lift the lathe. Once all sign of rock has disappeared nip the top nuts up. You can then start to properly level the lathe by test turning as shown in the manual.

Hope that helps.

regards Martin
23 August 2016 at 17:24 #252000
John Baron
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@johnbaron31275
Hi, the stud shown in the lower photo has been screwed too far down into the block under the foot. Slacken the nut underneath and screw it out until it is about two nut thicknesses above the foot. Tighten the nut and adjust the foot support nut as needed. Make adjustments to level the lathe as per the manual.
23 August 2016 at 17:35 #252001
MW
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@mw27036
If you are confident that the raised blocks on the base are okay(as in level), why not clamp away?

Edit: I would advise removing those nuts, i'm fairly sure the lathe is not supposed to sit on them like that, do what you have to do to be rid of them.

Michael W

Edited By Michael Walters on 23/08/2016 17:37:40
23 August 2016 at 17:46 #252002
Brian Wood
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@brianwood45127
Hello Michael,

Sadly I fear you are mistaken. The nuts as you call them below the feet on the bed are actually the heads of the jacking screws that are used to set the bed level in the first place. There should be fresh air under the feet when the job is complete.

I made my own up from 100 x 50 box section, but the principal is the same

Regards

Brian
23 August 2016 at 18:11 #252004
Ajohnw
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@ajohnw51620
The main thing is not to strain the bed when you fasten the lathe down. That's what the jacking screws are for. To make sure it's very evenly supported before it's held down. The bed doesn't need to be precisely level.

It looks like you may have what I usually do – a nut with a washer on top instead of real jacking screws. I think that the myford ones screw in and out of the holes in the lathe bed but to be honest I don't remember. Another type is a thin disc with a sleeve sticking up to fit the holes which screw onto the studs rather than into the lathe bed.

From memory you need thread diameter less around 20% of thread sticking out to fully use a standard nut. So a projection as long as the diameter should be just about enough for a nut and a washer.

In some ways it's best to "level" the bed using 3 of the adjustments and then carefully adjust the final one for no rock. An ordinary spirit level is fine for this. The super sensitive ones are used to check for bed twist and problems like that.

I think Harold Hall has a page on this subject. He may mention straining the bed to correct errors – not a good idea if there is any wear at all in the lathe bed or even eleswhere. It's only intended to correct really minuscule errors on lathes that in all respects are near perfect as they come out of the factory where errors could well be under a thou.

I tend to favour very light;y tightened nylocks if I can use them for holding the lathe down. Otherwise I just use finger tight nuts. That's me though. I don't want to strain the bed.

John

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Edited By Ajohnw on 23/08/2016 18:15:50
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