Lathe Cross Slide Problem

[EdK]

(04-21-2014, 09:47 AM)PixMan Wrote: Ed,

You can determine the thread pitch easily by how many thousandths of an inch the dial moves the slide in one rotation, as long as it's direct to the screw and not geared.

As for the mounting, it might be a wise idea to re-engineer the whole thing and get the nut mounted securely with two socket head cap screws from the top side and a cone point set screw between them to adjust/spread the split in the nut to reduce backlash. That's how my lathe is designed and it works perfect (once I get that special lockwasher.)

I'd be willing to make you a new screw and nut, so all you'd have to do is mill, drill and counterbore the slide in preparation for the new configuration. I would just need a centerline height of the internal thread on the nut from it's mounting surface, and dimensions for the screw's lengths and diameters. I'd make the nut out of 660 bronze as I did Darren's elevation nut and the screw from 1117CRS, 1144SP or 1045TGP steel.

Ken,

That's very generous of you and I think I'll take you up on your offer. I'll measure the thread pitch this evening. When I measured it I was in a hurry and was just looking for a rough idea of the thread dimensions. I had planned on doing exactly what you suggested using a dial indicator to get a more accurate measurement.

I want to machine the raw cast iron surface on the underside of the cross slide for the nut to mount on so I need to do that first since it'll affect the center-line height of the internal thread.

Thanks again!

Oh, and did you see this link I posted in another thread of a source for the bearing lock washers? http://www.jwwinco.com/products/section13/mb/

Ed