Machining A Stirling Engine

[Magoo]

So I've been a machinist for 12 years now. Seems to me a personal project that's also a bit of a rite of passage for machinists is making your own steam-esque engine. Well, I was flipping through the tool vendor catalog at the shop today and came across this little kit here.

https://www.travers.com/product/ttc-...set-61-251-705

Well, I've never done it, sooo I picked a kit up. We'll see how that goes!

[XEMON]

Seam like a cool little kit.
I've thought of trying one a few time.

Feel free to share/make a build thread to keep us to speed.

[Magoo]

Sorry, I guess that's a bit of a teaser. I'll absolutely do a little write-up with some pics as I go. Anyone else into things like this? Doc??

[Magoo]

Okay. The kit arrived last week, and I gotta say... hoo whee. I was expecting something a hobbyist could do in a garage, but this kit calls for some seriously tight tolerances. They want +/- a few ten thousandths of an inch in some places (called "tenths" in the industry, since a thousandth is it the standard measurement), and that requires more than I can do on a manual. Looks like I'm gonna have to CNC a lot of it. What surprised me was that the prints actually use GD&T tolerancing. This kit is more professional than a lot of our clients and we're in the aerospace industry!

I have yet to inventory and size the material provided, but that should be the first major step.

This is gonna be fun!

P.S: It's a Stirling engine, not a flame licker (or vacuum) engine. I'll edit the title to reflect that. I've been doing a lot more research on older style engines. They're super interesting.

Edit: I guess I can't edit titles. I probably ought to regreen. Lost my status in the Big Hack.

[Axel]

I gotcha.

GD&T... Now there's a special language. You'd expect they teach it in engineering school, but no.

[Magoo]

Gracias.

I guess "GD&T tolerancing" would be like "ATM machine," since the "T" actually stands for "tolerancing," but I figured it would be a quick way to convey the intent to those not in the know without making em Google.

The long made short of it is "Geometric Dimensioning and Tolerancing." It's like an industry standard for labelling prints to convey dimensional and tolerance requirements. It gets... in depth sometimes.

[BlindFaith429]

I have one of those little sterling engines you can get off Amazon that sit on your coffee cup. Not nearly as intricate as what you're undertaking.

Id love to have a shop to do one of these kits. At my old job (designer in a machine shop), I had free reign of the tool room (for personal stuff after hours) or to make prototypes of the things I designed. I learned so much there, and loved doing little projects in the tool room. Biggest thing I miss about that job lol.

Would love to see the progress as you go.

And yeah, GD&T is kinda surprising for something like that, at least to me. I had to use it on some of my parts I did, but the vast majority didn't require them.

[lhamilton1807]

I’ve long wanted to get a stirling engine and heat it with a mirror-lined satellite dish. Just because it’d be cool.

Of course I’m not a materials engineer or a machinist with big boy tools, so I’d have to buy the Amazon/coffee cup variety with loose tolerances. Something tells my my angle grinder won’t get things to within a few ten thousandths of an inch of spec 🤪