First engine, material choices

Jkrych · Aug 24, 2018

finally going forward with an engine build. i'd like to get at least moderate performance, but i'm going to build a test platform prototype, which brings me to my question:
Ive decided on a steel liner, aluminum piston and cast iron rings. I know this is more difficult than say a steel liner CI piston, but i'm confident in my abilities to maintain dimensions. however i have a few choices of steel and i'm not sure which one would give good results. with a CI ring, 12l14 is out for a liner, so i was going to use 1144 or some chrome moly tubing- honed circular and then cross hatched. i have some 1215 steel in the right diameter for the crankshaft, but are "easy machining" steels suitable for a crankshaft? i was going to use a pressed in pin and a bush on the con rod big end. my alternatives are some 1018 and 1144. also, i should assume low carbon steel is not suitable as a liner material?

Cogsy · Aug 24, 2018

12L14 is a great liner material for use with CI rings - just look at Steve Huck's engines. Personally, I'd be using 12L14 for the liner and 1144 Stressproof (stressproof is important) for the crank and turning it in one piece.

Jkrych · Aug 24, 2018

12L14 as a liner with moderate performance goals? im planning on sport running the engine

Cogsy · Aug 24, 2018

What do you anticipate the problem to be? It machines well and runs well with CI as far as I know. Steve's V8 and V4 must have many hundreds of hours of running and haven't had any issues. I think George Britnell may use the same configuration but I'm not 100% sure.

Jkrych · Aug 24, 2018

maybe my amateur status with metallurgy has me confused, but my logic is telling me a material that is easy to machine would also wear away faster than a material that is more "difficult" to machine.

Cogsy · Aug 25, 2018

There is a lot more to it than ease of machining, or even hardness. Cast iron and bronze for example, they're both easy to machine and have fantastic wear/bearing properties. It's more about properly matching pairs of materials for the best characteristics rather than individual characteristics of each material. To take it to an extreme as an example, running a hardened needle roller bearing on a non-hardened shaft, the assembly will fail in no time at all because of the differences in characteristics of the materials. Put the same non-hardened shaft in a bronze bush and it'll run for years (properly lubricated of course) without appreciable wear.

natalefr · Aug 25, 2018

For the first engine, follow the instructions of the person who carried out the project and you will have a functioning engine, then with experience, you will be able to make modifications, usually before running, you will learn to walk

goldstar31 · Aug 25, 2018

Perfidious Albion?
N

natalefr · Aug 25, 2018

I have already built 3 engines and I start the Hupshur Twin, I think that before starting to experiment with different materials, it is necessary to have a good experience and to be encouraged by the success of the previous constructions.
For example, in the Upshur that I built, I had a carburetion problem, the engines remained on for a maximum of 2 minutes, I discovered that the intake line was very hot, I spoke with a friend more experienced than me, we understood that the fuel evaporated before being sucked, I extended the intake duct and now the engine stays longer running. Start a motor by changing materials and if that does not work, becomes a difficult puzzle to solve and discourage the enthusiast
It's my humble opinion

WOB · Aug 25, 2018

Cogsy said:
12L14 is a great liner material for use with CI rings - just look at Steve Huck's engines. Personally, I'd be using 12L14 for the liner and 1144 Stressproof (stressproof is important) for the crank and turning it in one piece.

Excellent suggestion.

WOB

Jkrych · Aug 25, 2018

Thanks for the insight.

First engine, material choices

Help Support Home Model Engine Machinist Forum:

Jkrych

Member

Cogsy

Well-Known Member

Jkrych

Member

Cogsy

Well-Known Member

Jkrych

Member

Cogsy

Well-Known Member

natalefr

Well-Known Member

goldstar31

Well-Known Member

natalefr

Well-Known Member

WOB

Well-Known Member

Jkrych

Member

Similar threads

Latest posts

First engine, material choices

Help Support Home Model Engine Machinist Forum:

Member

Well-Known Member

Member

Well-Known Member

Member

Well-Known Member

Well-Known Member

Well-Known Member

Well-Known Member

Well-Known Member

Member

Similar threads

Join the conversation!

Join today and get all the highlights of this community direct to your inbox. It's FREE!