The Home Machinist!

There is a fundamental difference between the various thread generating methods. When you single point with the top of the tool level, you get an Archimedes thread. In cross section the thread flanks are straight lines, just like the sides of the cutting tool. If you tilt the cutting tool to match t...

It's a downhill slope. If you get a Variac, you'll then find you need a voltmeter and an ammeter and maybe an isolation transformer. I use one in the electronics lab for powering up old and suspect equipment, but how often do you do that? For hot knives and such, you really need that isolation trans...

Or, somebody might have had a bunch of 9/16" tool steel they thought would be handy for making boring bars. Or ten other reasons. I doubt it's an error because you'd drill the two holes right after each other in the mill. You'd have to work really hard to make that error.

FWIW, my entire career I've worked with very smart PhDs who could do complex math in their heads. Many/most were entirely resistant to learning anything about machine capabilities, processes or practical design. Some had no qualms about reducing part tolerances to zero. We school-of-hard-knocks peop...

I've never understood the lack of a table lock. At the very least you need it for dressing the wheel so the diamond doesn't creep. I think it's possible to move the stops in so they both contact the push thingie, but that's a pita. Better to make a dedicated part, but I've never really looked at wha...

Empty tuna cans are the rule, because machinists eat tuna fish sandwiches for lunch.

I bought one long ago because it was something you were supposed to have. Over 30 years or so it probably takes the award for the least used tool in the shop. Based on that, material wouldn't matter much.

Don't grind dry. That way the mess will be localized. Dressing the wheel goes everywhere but drops quickly and I just sweep if off the cement floor.

I've used some pretty old way oil, but after a while I found it leaves a varnish. That's probably the time to dump it and buy new. There are lots of people bottling up the right lubes for SBs.

I don't like winding springs on the lathe; seems dangerous. I use a fixture with a drill chuck and a hand crank.

I bought a fixture to sharpen the ends on my surface grinder. The fixture works well enough, but you have to shorten the end mills a bit if you can't grind the flutes. Given the cost of a decent 1/2" end mill, I think it's worth it, but not every end mill can be saved. OTOH, "real" ma...

You can buy colorants for epoxy. Pick a good one and mark tools with that. You can get really creative and mill a small spot and fill it with color. Fairly hard to remove, at least harder than most paints.