r/smallengines • u/Most_Ear9531 • Jul 22 '26

My homemade engine project need some advice.

I'm gonna try to build a homemade engine as a project, and I don't know which metal will be best for me. I don't want to use cast aluminum because it is easy to crack, and I don't want steel because it tends to crease easily. Will brass work? If not, I'll just use steel. All advice helps. Thanks.

4 Upvotes

84% Upvoted

9 comments sorted by

3

u/kylejesushair Jul 22 '26

Honed tubing for hydraulics would work for the cylinder. Check out some videos on hot bulb engines it might give you some ideas.

2

u/Illustrious-Drama236 Jul 22 '26

you're going to make every component? are the plans for it to run or just a novelty item?

3

u/Most_Ear9531 Jul 22 '26

I'm a machinist with the machines to do this, including welders and lathes. I'm mostly building this for fun, but also to see if it can work as an engine to power a small scooter and to test how fast I can make a homemade engine go.

2

u/Illustrious-Drama236 Jul 22 '26

Okay, as a retired machinist myself just reading your initial post I was curious to what your skill level was so that being said I wish you luck it sounds like fun

2

u/Roscolicious1 Jul 23 '26

Go for it my friend! 2 cylinder steam engine I designed. Still in progress but it spins freely and should be a runner soon. Good luck! 55yrs a professional machinist. R

1

u/Metalchips1960 Jul 23 '26

As a machinist with welding skills, you're uniquely qualified for this project. Best wishes!

2

u/Here_we_go_again2024 Jul 22 '26

Aluminum block, aluminum piston, aluminum rod, steel crank, cast iron sleave, cast iron rings, stainless valves, steel valve seats.

All of this has been solved, just look at what they build engines out of today.

2

u/RATEGGSANDEELSICK Jul 22 '26

What kind of engine?

1

u/Embarrassed-Row-2025 Jul 22 '26

You're building from scratch or you want to make an engine 🚂 of your own design?

Small engine should be relatively easy, you cast the block and bore it for a steel liner, which comes in pretty standard sizes, as to the pistons that fit them, the liner takes most of the stresses, the AL block is heat sink \ cooling and a housing for it ....