The "polished" AL80 scuba tank...My experience

[tech3324]

Nice work! Kind of makes me want to try that.

Worst case, if it fails hydro, you have the makings of a truly beautiful and unique lamp.
But I'm betting it passes.

 

[cliffoco]

Passed hydro, they already scuffed the side but oh well. At the LDS now to get a vis

 

[Compressor]

Beautiful job.

 

[gfaith]

In the immortal words of my sons "Sweet".
You know a AL13 would really make a cool unique lamp Thanks @tech3324

 

[Tracy]

No worries, you have actually strengthened the tank by polishing it. Aluminum is weakest at a stress riser and by polishing, you have removed most risers. This is the reason airplane parts are polished, less prone to cracking.

 

[cliffoco]

It passed VIS, they were impressed and said they were really only worried about everyone asking me to do it to there tanks. HA. Had I not just had a hydro I think they would have been reluctant, and possibly rightfully so as they do not know just how much I sanded down other then to just "trust me". I guess they could still see the original brush marks but still.
There was a dent in the tank (bought it used) - it wasn't an issue this time but they did notice it. Would this be dangerous for the guy filling? (the dent is about a dime in width and deep enough that you can see it. Similar to when a car door hits your car in a parking lot...

 

[lowviz]

...//... There was a dent in the tank (bought it used) - it wasn't an issue this time but they did notice it. Would this be dangerous for the guy filling? (the dent is about a dime in width and deep enough that you can see it. Similar to when a car door hits your car in a parking lot...

It passed hydro. That liability is on them, not you. That is why you have to pay to have your tanks tested. You can do things to a tank that will fool a hydro tester, like sanding way, way down. Nothing is perfect in life. If you just polished out all the brush marks then I would just dive it and enjoy it without a second thought.

Don't ever overfill an aluminum tank, aluminum isn't steel. I overfill steel regularly, but never aluminum.

 

[The Laconic]

Pretty!

Ordinarily this is one of those photos where you suddenly notice the reflection of the photographer, and he's nude.

But not in this case. Well planned!

 

[cliffoco]

Pretty!

Ordinarily this is one of those photos where you suddenly notice the reflection of the photographer, and he's nude.

But not in this case. Well planned!

Ha, yeah good thing. It's actually a t shirt that I got from Deep 6! Coincidence

 

[rjack321]

It passed VIS, they were impressed and said they were really only worried about everyone asking me to do it to there tanks. HA. Had I not just had a hydro I think they would have been reluctant, and possibly rightfully so as they do not know just how much I sanded down other then to just "trust me". I guess they could still see the original brush marks but still.
There was a dent in the tank (bought it used) - it wasn't an issue this time but they did notice it. Would this be dangerous for the guy filling? (the dent is about a dime in width and deep enough that you can see it. Similar to when a car door hits your car in a parking lot...

For 3AL specification tanks the maximum allowable pit depth is 0.06" which is surprisingly deep. If it passed both hydro and vis then I think you can safely assume that dent was checked (twice).