Which Grade of Bronze?

[dkaustin]

I could use some advice on which grade of bronze to use for my projects.

The plans I have spec bronze for such things as slide valves and eccentric straps, but they don't specify which bronze alloy to use.

Tho only bronze alloy which seems to be available in rectangular flats is aluminum bronze. I get the impression from other machinists that aluminum bronze is a very demanding material that can be hard to machine successfully. I also get the impression that 660 bearing bronze and manganese bronze are easier to machine, but I have only seen them offered in rounds and cored rods.

Given the shocking price of all the red metals right now, I'd rather not have to hog square and flat pieces out of a big piece of round rod and throw most of it away as swarf.

Am I missing something? Is there any reason to shy away from aluminum bronze for home shop projects?

Thanks for any tips.

 

[MachineTom]

I just looked at MSC, 660 and aluminum Bronze same sizes close in price, all expensive. Just keep looking, ebay as well.

 

[kvom]

I'm using 660 on my loco build for all the bushings, slide valves, etc.

For eccentrics, a cast iron eccentric with a steel strap is quite a bit cheaper than bronze where a larger diameter is needed.

 

[dkaustin]

Thanks, kvom.

I was thinking seriously about the CI/steel pairing for the eccentrics. Always good to have a reality check from someone with more experience.

 

[Noggin]

Aluminium bronze ir really tough. have a think about using PB102 which comes in a limited range of squares, flats and plates.