Question DIY Paint Scuba Cylinders?

[SlugLife]

How many shops do you frequent for fills? I use 3 and know the fillers by name... most others only know to look for stamps and stickers

Mostly one shop due to location, but there are a couple more available with more driving. I've had trouble with this shop before. I typically see them check the hydro and VIP, but you never really know if they look for other things as well.

I've only had a fill refused once (aside from expired VIP). It was a guy who had a fill-station in his garage; and he noticed the 1987 manufacture date on 2 tanks. He said he'd fill them this time, but only this time.

I've had some painted tanks for the last 25 years and have never had a tank rejected (only had fills in Wisconsin, Minnesota, Missouri, and Florida). I have had issues with some LDS and my old tanks - but not because they were painted and I no longer visit those LDS. I am VIP certified and understand the issues around painting tanks (those trying to cover up stuff), so can see where a tank could be rejected. I would recommend painting before hydro (but it is easy to paint after hydro and have it look like it was before) - but if they are good clean tanks it should be rare to have issues. I now VIP my own tanks so I know what they looked like before and after painting, so never have an issue - but again never had an issue getting a fill or vip in the past due to painting. I've never had my vip stickers refused (or even questioned) either but I've heard it happens.
I've heard that there are dive stores that won't fill 10 yr old tanks no matter what, those that have no understanding of the metals, DOT markings, Plus stamped steel tanks, etc, etc, so will you never have issues? who knows - if you do, and that dive store can't make a sane argument/reasoning that matches facts - best to just find another dive store.
So if you want to paint your tanks, understand some won't like it. If you are traveling a lot, you will want to call ahead and talk to the shops you are planning to get fills at. If you are diving locally, talk to your local dive shop. I like the tanks I've painted - but you'll have to decide if it's worth it for you.

That's some good data.

I have thought about making the paint look like it was pre-hydro. If the first-tank I paint needs hydro, I'll have a perfect example of what it should look like after. I'm probably also going to start VIP-ing my own tanks in the near future.

The main thing I've heard about refusing fills is shops that refuse either pre-1990, or pre-1988 aluminum tanks. 10-years is awfully short; and any shop that strict would probably lose a lot of business. But like you said, dive-shops often don't know what they're doing.

 

[Eric Sedletzky]

I may have the perfect test-case tank. A 2003 tank, never hydrod, VIP'd once in 2004. The guy claimed it has been in storage for as long as he knew, and had no idea about the tank's history. Apparently he was a military diver, he knew how to dive, but apparently didn't know much about equipment nor dive recreationally. At $25, worth the risk.

The inside of the tank was clean. I stuck a flashlight inside, and threads look good, and tank just looks like bare metal.

The outside is another story. Valve had a medium-high amount of corrosion on it's exterior, but was yoke meaning it's being replaced anyway. The paint was a pretty blue color, however it's bubbling with white powdery stuff underneath (presumably aluminum corrosion). In the areas I manually sanded so far, the metal underneath ls smooth and no signs pitting. I'll finish either when I sand-blast it, or a warmer day when it's more convenient to use some paint-stripper outdoors.

In other words, the paint needs to be stripped anyway, and a protective-coating would be nice. I can imagine a scenario where a dive-shop may notice the bubbling and refuse a fill or fail-VIP. It needs hydro as well, so might as well paint before hydro.

My plan for dealing with dive-shops is (1) start with a single tank, and see if local dive-shops give me trouble. (2) if I run into trouble, have photos of the stripped tank easy to access, along with showing the paint is air-cure (3) If all goes well, it might be fun to even sell/swap the painted tanks with other locals. Not as a business, but rather a distraction and practice, and something to do as I slowly upgrade to newer tanks and/or more Steels.

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If that was my tank, I would strip off the paint and polish it out. The best surface for aluminum AFAIK is bare open polished metal. It breathes and won’t corrode, nowhere for white oxidation to start under any paint film.
And they look cool too.

 

[SlugLife]

If that was my tank, I would strip off the paint and polish it out. The best surface for aluminum AFAIK is bare open polished metal. It breathes and won’t corrode, nowhere for white oxidation to start under any paint film.
And they look cool too.

I have a 2 polished tanks and they look great!

 

[Tracy]

I happen to have several tanks, some with worn-down, chipped, or ugly paint. I also have some (no-bake) Cerakote, a extremely durable ceramic-based paint often used on guns, and was thinking my scuba-tanks would make a great practice-surface, and possibly some cool art-projects!

The basic process is to sand-blast the surface, paint with an air-gun in several very thin layers, and then let dry. My basic thinking is to install a "garbage" valve, sand-blast, paint, re-install my good valve, and move onto the next cylinder.

That leaves a couple interesting questions:

• Would you be concerned about sand-blasting near the markings on the top of the tank?
• What about the "Warning" stickers on the bottom of scuba-tanks. I could mask them, but I'd prefer to remove them and paint the whole cylinder. Should I just remove them and leave them removed? Should I replace them? The stickers say to not remove them, but otherwise don't really say anything too interesting. Would scuba-shops not want to fill cylinders which lack that sticker?
• Is there anything stupid about this idea? Anything I'm missing?

Most of the tanks I sell get sandblasted at hydro. The aluminums stay bare and the steels get an industrial epoxy paint.
No harm in sandblasting the tanks. Every industrial bottle you see gets blasted and painted every ten years when it gets hydroed.

 

[Tracy]

As an FYI, these three tanks were identical. You can see the before on the right, left is after hydro and blast.

 

[SlugLife]

Most of the tanks I sell get sandblasted at hydro. The aluminums stay bare and the steels get an industrial epoxy paint.
No harm in sandblasting the tanks. Every industrial bottle you see gets blasted and painted every ten years when it gets hydroed.

The silver (natural) color is pretty! And thanks for the info on sand-blasting.

I'll have to get my sand-blasting rig setup; mostly something to capture and recycle the "sand" that's big enough for a scuba-tank.

 

[Tracy]

The silver (natural) color is pretty! And thanks for the info on sand-blasting.

I'll have to get my sand-blasting rig setup; mostly something to capture and recycle the "sand" that's big enough for a scuba-tank.

Unless you use a scuba shop for hydros, your retester most likely has a tank blaster on site. It usually costs less than $10 to have them blasted while at hydro.
Not really worth the time of doing it by hand.

 

[SlugLife]

Unless you use a scuba shop for hydros, your retester most likely has a tank blaster on site. It usually costs less than $10 to have them blasted while at hydro.
Not really worth the time of doing it by hand.

That's VERY good to know, thanks! I have taken most of my tanks directly to a hydro-place, and not a scuba-shop. The one time I was lazy and dropped a tank off at a scuba-shop for hydro, it turned into a bad experience.

Anyway, I'll call up my usual place and ask if they have a tank blaster and the price. At $10, it would probably cost me more in labor and lost blasting-media to do it myself.