Aluminum Piston Material sources?

[1Kenny]

Here is a good article about piston material that is used.

http://www.kb-silvolite.com/article.php?action=read&A_id=38

I have used both forged and hypereutectic pistons in engines. They both have their place depending on how you are going to use the engine.

Kenny

 

[raym 11]

Thanks for the article
Kenny. I need all the help I can get.
My latest build was the VAL (#15&16 Model Engine Builder). Photo in issue #20.
It has a 1.124 bore. I used 4032 and allowed .0015 clearance using the criteria atwww.eriperformace.com. The engine turns ~9k .
I often build less demanding engines and try different materials as a test platform. Only one to destruction so far. ;D What a hobby!! :

Ray M

 

[1Kenny]

Here is what Alcoa says about the 4032. It has pictures of the grain too.

http://www.alcoa.com/gcfp/catalog/pdf/alcoa_deltalloy_4032.pdf

I have had a few beers with one of the engineers at KB. He has told me that he has run as little as .0005 clearance with the hypereutectic pistons with a 4" bore on an air cooled engine. To do that, the bore needs to be straight and round using vertical boring. Gravity pulls the stone down and will oblong the bore when done horizontally. The bore needs to be smooth. Almost like it is polished with so lite of a 60 degree cross hatch your mind will question if that is right.

Kenny

 

[Kaleb]

I am using an aluminium piston in my steam engine build, and I go to a shop called Bearfast, which deals in general tooling and industrial supplies, for all my brass and aluminum. A 300mm length of approx. 12mm diameter aluminium bar can be had there for about AU$5.