Has anyone made their own machinist jacks?

[hman]

The ball on top is tool steel I hardened. Made some mistakes on this project but it still works proper.

Nice differential thread!

 

[pstemari]

Havent' made my own jacks but if I do, I will use this to do the black oxide.
http://www.caswellplating.com/metal-finishing-solutions/black-oxide-kits.html
... It's A-OK stuff and I do believe meets mil-spec. The chemicals are not outwardly nasty and it's a cold process. ...

Nope. It's a selenium-based blackening process, not black oxide at all. I have a small jar of the oxpho stuff, which uses the same chemistry, but haven't used it yet. I'm a bit leery of the selenium: it's pretty toxic in measurable quantities, and I haven't been able to get a straight answer on whether the coating (copper selenide) poses a long risk when handled with bare hands. Calling the process "environmentally friendly" because it uses less electricity is a bad joke.

True black oxide is magnetite, and totally innocuous. Unfortunately, the process requires super hot solutions of concentrated lye, which can spatter violently if you need to add water to make up for evaporation.

 

[dennys502]

These are over 40 year's old so they aren't very pretty.
I used them mostly for die jacks when building tooling.

 

[chips&more]

I can count on one hand the times I used machine jacks in the last couple of decades. And there are sooooooo many work arounds to do the same thing. And on top of that I have collected an embarrassing amount of machine jacks over the years. Don’t need to make any.

 

[kwoodhands]

Without getting fancy and in a pinch, I have used bolts, nuts, and coupling nuts as jacks. It is a really thrifty alternative.

I have a couple of the small machinist jacks but one day I needed shorter ones. I installed a couple of 3/8" TEE nuts in two pieces of wood for the base. Then machined the heads flat on two 3/8" bolts. Works fine, no need for a tommy bar or even a wrench. Cheap too.
mike