Aluminum Thunder Mugs

[Treeburner]

Recently there's been a trend in creating large bore signal cannons from aluminum. This is typically a no-no, but very well-known sellers like Pyrocreations are claiming these pieces are safe as noisemakers only (no projectile) and I haven't seen any catastrophic failures documented. Here's what one seller has to say about the materials:

 

"It is made from 6061-T6 aluminum alloy. T6 temper 6061 has an ultimate tensile strength of at least 42,000 psi (300 MPa) and yield strength of at least 35,000 psi (241 MPa). More typical values are 45,000 psi (310 MPa) and 40,000 psi (275 MPa), respectively."

 

So can anyone comment? I know just because no failures have been documented doesn't mean they're safe, but can anyone explain why anyone firing an aluminum thunder mug is risking life and limb?

 

Thanks,

Treeburner

[dynomike1]

I wouldn't mess with them. The thing about aluminum every time you stress aluminum it weakens minutely, also you are going to have corrosion problems. If you are thinking about a Thunder mug i can put you on someone that would make it cheaper and safer. Check out Dominick Carpenter.

http://blackpowder-cannons.com/index.htm

Edited March 11, 2016 by dynomike1

[Treeburner]

Thanks Dynomike, considering one of his 1.25" bore thunder mugs since there's nowhere around here to fire golf balls or cement soda cans.

 

-Treeburner

Edited March 13, 2016 by Treeburner

[Treeburner]

Actually could one of the golf ball mortars from http://blackpowder-cannons.com/index.htmbe used for salutes with kitty litter wadding rather than firing a projectile? Don't know how much more force that would impart on the barrel, but most of my thunder mugs have a wall thickness equal to the bore.

 

-Treeburner

[dynomike1]

Yea that would work. I don't know about putting kitty litter in it. On my 2 1/4" i roll a canister shell out of aluminum foil and put it in the barrell. What ever powder load he recommends using a ball, you can double that on a blank. I have read about a lot of accidents on account of putting wadding in them. Especially wet paper towels. Send Dominick an email he will be glad to answer your questions.

Edited March 13, 2016 by dynomike1

[Treeburner]

I think the issues with wadding are typically when putting wadding over a projectile which causes a bore obstruction when the projectile gets hung up in the wadding and can't exit the barrel, but trying to find someone who accepts paypal or credit cards anyway.

 

Thanks for the info!

 

-Treeburner

[pyrokid]

Can you all elaborate on these accidents that occur with paper wadding? I can only think of one type of accident that might be associated with barrel obstructions, and given that these barrels are made out of steel it is kind of frightening.

 

What is the appeal of signal cannons anyway? Salutes are just as loud and leave less evidence.

[Treeburner]

The appeal, at least for me, is legality. A BP muzzleloading signal cannon is legal to fire here, a homemade or even commercial firework is not without a license and permit. After firing my .45" and .75" bore mugs today I think I'm gonna stick with my 1" for my biggest mug for now, as that's loud enough. And I was not really considering aluminum as I intend to have these forever and pass them down, and wouldn't want something that is getting more and more risky with each shot. Thanks for the info!

 

-Treeburner

Edited March 13, 2016 by Treeburner

[Fulmen]

every time you stress aluminum it weakens minutely

While technically true, this only becomes an issue beyond 1000'000 cycles. Below that the fatigue properties are pretty similar to that of steel. I seriously doubt that anyone will fire such a device anywhere near that number (27 times a day for a 100 years)

[dynomike1]

I wouldn't think much about it if it had a steel liner. As far as it goes you can even buy a steel one cheaper than aluminum. You are probably right Fullmen, but there is another issue of corrosion.I also question whether the proposed dimensions would work well (the bore is going to be relatively short with a 5" overall length.

[Fulmen]

Corrosion would be my first concern as well. It's probably manageable with some care, but I suspect it would turn quite ugly if not cleaned after each use. Steel and iron might rust a bit, but not anywhere near aluminum in alkaline environment filled with nitrate residue.