Casting aluminum bronze

[RufusToad]

Hi all,

Not sure if I am in the right place but I am starting to cast my own stuff and I am gearing up for casting a bronze napoleon style cannon. I thought some older folks in this forum would have good experience in casting and I was wondering if there is any better materials that I should consider using to cast this other than Aluminum Bronze?
I was also wondering if there is an aluminum that should not be used for casting? I have a bit of machined aluminum scrap from work that someone told me may not be the best to use to melt but I just don't know enough about machined materials to tell. I would think that aluminum is aluminum and would work no matter if its 2024 or 6061 for casting?
I was also wondering if someone may have a good recipe for aluminum bronze other than the basic 90% copper 10% aluminum? I have been told to splash a bit of borax, salt and a little pepper to taste

 

[Phil Coffins]

What’s the silica content of the scrap from work?

 

[RufusToad]

What’s the silica content of the scrap from work?

Hi, I am not sure I could tell that? Is there a particular way to check this?

 

[Phil Coffins]

Use a spectrophotometer. If you intend to make a cannon you would be well advised to know about the strength of materials. A lot of data is in the Machinist’s Handbook.

 

[Commodore Swab]

Silicone bronze is a good option. What size are you thinking?

 

[Gun Tramp]

Silicone bronze

Silicon bronze.

 

[RufusToad]

Silicone bronze is a good option. What size are you thinking?

I am looking at something small right now like a 50cal. I was under the impression that aluminum was a bit tougher and less friction than silicon?

Not quite sure a spectrometer is in the budget right now. I decided to melt some last night and found it to be pretty clean and it machined very nicely.
I am really excited to give this a go as I have a ton of bushings to make for my dozer

 

[Youngblood]

Use tin with your copper to make bronze.
Gun metal bronze is 88% copper, 10% tin, and, 2% zinc.

 

[Clark Badgett]

Use tin with your copper to make bronze.
Gun metal bronze is 88% copper, 10% tin, and, 2% zinc.

According to my 1847 Engineer & Mechanics handbook Naval bronze was 90/10