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Now the fun part!

The factory Nichols halfnut is cast iron, and rides on a relatively hard leadscrew.
The nut is a somewhat "softer" material, and is designed to wear first, before the leadscrew does.
This is simply done because the nut is easier and cheaper to replace than the screw. Virtually all
machine tools use this same idea, running the hardened and polished screws in brass or bronze nuts.

I wanted to use this same technique here, but I had a bit of a dilemma.
Make the entire nut from bronze, and I was afraid I'd be sacrificing some strength
where the nut is bolted- by a single 3/8" bolt- to the saddle. I'm told most of the factory
cast iron nuts broke at the mounting bolt. Or, have a stronger piece by using steel...
but then running a steel screw on a steel nut. The screw is hardened some, but I'd
still be risking galling and relatively rapid wear.

The solution, of course, was to combine them.

So, I made this base of steel, with a nice, hefty mounting flange.
For a bearing surface, I brazed silicon-bronze brazing rod into the
hollow of the steel weldment I'd just made. I'd been forced by circumstance
to use a very large oxyacetylene torch for the brazing, and so lost some
delicacy. On the positive side, I got a very nice fusion, virtually no
voids or gas bubbles, and plenty of meat to machine to spec.





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Information contained in these pages is for reference and entertainment purposes only.  Our methods are not always the best,
quickest, safest, or even the correct ones. It's up to you to know how to use your own machines and tools.
Keep your fingers away from the spinny blades o' death and you should be all right.