Used Tanks/Valve Change Questions

[Ian Fatzinger]

Hello all!

I just purchase 4 used AL80s here in Hawaii. I am planning to swap all the valves for the DGX Sidemount Modular valves (two sets of sm tanks) and I was wondering how/if I need to do that prior to hydro/vis.

I also wanted to inquire on the best way to refurbish these tanks. Super old paint that is chipping off in the back of my car lol. Definitely wanting to know the best way to remove the paint. I've seen multiple articles about whether or not to use primer vs. a 220-400 grit sandpaper. LMK

Thanks!

 

[Bob DBF]

If you are going through your local dive shop, swap the valves out before you send them in for hydro.


Paint on aluminum tank

 

[elan]

Hydro facility does not care - I always send my tanks valveless. The shop that will do the vis (although vis is part of requalification many shops still do their vis) will want to have the valves installed right after the vis is done so they fill the them. What I would do in your case if you do the vis and hydro through the same shop is strip the paint first then give the tanks to the shop together with the new valves (packaged - I assume they are new). They will send them for requalification then do vis/o2 cleaning and install the new valves.

 

[broncobowsher]

Most of the big hydro shops will strip the tanks. I've had some stripped and repainted. Pretty sure it was a form of blasting that didn't remove the prior tank stampings. Which is important if you want more than wind chimes.

As for the valves, the dive shop will install them as part of the VIS (they have to be out to inspect inside). I would show up with the valves already installed (loosely) in the tanks. Minimizes the chances of the old valves reinstalled, new parts lost, etc.

 

[blue sky]

I found this Luxfer guide on line several years ago. I found it very useful when I refurbished several tanks. It also provides data on allowable pit sizes.

 

[edwants2dive]

Citrus strip works great on the paint and doesn't affect the metal

 

[Sawdust82]

Ive been wondering this also. Would something like soda blasting or walnut shell blasting work without damaging the aluminum…?

 

[Ian Fatzinger]

Update: Used citristrip, some steel wool, a wire brush, and plastic scrapers. A complete bitch to do, but got it done and the tanks look incredible. Didn't take any actual metal, but definitely removed the oxidation layer.

 

[Lostdiver71]

I use CitriStrip on aluminum tanks and just leave them bare, no need to repaint.

 

[Ian Fatzinger]

I use CitriStrip on aluminum tanks and just leave them bare, no need to repaint.

yeah left mine bare. super pretty