AL tank expansion question.

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Hello,

I have a AL catalina (sport chalet) tank that I bought in 2001 for the purpose of air fills for my paintball marker and on one outing I noticed that the tank had expanded so much that it split the plastic boot. Recently I have been thinking about taking it out diving but was unsure of the safety of a tank that has been expanded that much. So I guess my question is, can a AL tank expand to that degree and still be safe or am I better off just ditching it and getting a new one. Any help or information is greatly appreciated. Thanks
 
I doubt your tank expanded that much alone to split the boot, but with the heat might have.

Since you are in LA, you've likely taken the tank to places such as SC Villiage, where the temps during the summer to way too extreme. Often over 110. Leaving the tank out in that temp isn't good, plus, your boot will expand and contract and this might make it split.

Since the tank is older, you'll need to have it inspected and get new tags before you dive.

A new tank is $110, not that much.

Xanthro
 
A couple trips to SC village and California Paintball Park and I noticed the split boot. I think I'll definately spring for a new tank instead of getting shredded by shrapnel. Any ideas on what to do with an old scuba tank? Does anyone take them for recycling?
 
lowlight:
I think I'll spring for a new tank. Any ideas on what to do with an old scuba tank? Does anyone take them for recycling?

They make nice bells (cut in half)!
 
The boots on all 3 of my Catalina 80's cracked like you describe above. The boots cracked because they shrank, not from the tanks expanding. My tanks are fine...just passed a fresh hydro. $15-20 for a hydro is a lot cheeper than a new tank.
 
Our rental tanks see that kind of heat daily not enough to harm the tanks. If you are worried get it hydroed but I don't think the tank expanded the plastic on the boot is the problem.
 
Aluminum tanks really don't expand much, so your boot probably deteriorated and split on it's own. If you are concerned, get the tank hydro'd and inspected by a certified facility and then you can use it for diving all you want.
 
*if* the tank expanded that much once, it will fail a hydro test.

No need to dump it right away. Get it hydro'd and visually inspected. It is probably OK.

If it isn't. Scrap dealers like them. Garden Gongs. Table lamps. Paper weights.
 
Frank is right. The plastic split because of heating/cooling cycles, not because of the tank expanding. Don't worry about it, but if you are still worried about it, send it in for a hydro test. If it passes you're golden.

Don't buy a new tank.
 
I agree that the most likely problem is the plastic became brittle and split. You are about due for a Hydro anyway. Get the hydro done. If it fail, AL scrape is about $35 to $45.

But you should make an effort to keep your tanks out of the sun, and store them in the upright position. A local diver here in LA last year had his tank in the car all day for an after work dive. Drove for an hour to get to the dive site before the safety plug let go. Made a mess in his car (he did not mention his pants) and he did not get to dive.

You are right about not wanting to be around it the the tank blew. They do make a mess and pack a punch.
 
https://www.shearwater.com/products/teric/

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