Tank refinishing

[Ed Palma]

Earlier this week, I purchased 2 vintage Dacor LP72s. I posted in the basic scuba discussion forum about using steels in tropical seas, and this is the offshoot of that thread...

I bought the tanks based on some grainy photos from the web. After getting them, both tanks are in relatively good shape (at least externally thus far)

The tank numbers are as follows:

DOT-3AA 2250
74345
DACOR
8(L)75+ PST

DOT-3AA 2250
61794
DACOR
10(L)72+ PST

I take it then that these tanks are from 1975 and 1972 respectively. What I'm not sure of is if DACOR was the manufacturer or was PST?

And shouldn't the + sign be after the service pressure?

On the opposite side of the shoulder, both are stamped 1(S)84. So I guess both tanks were re-hydroed back in Jan of 1984. And have not been re-qualified since...

These are the tank:

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Started stripping the blue tank:

[/IMG]

Which came right off:

[/IMG]

Leaving me with this:

[/IMG]

Now, I think the base layer is an epoxy coat, and before I think of doing anyhting more to these tanks I need your opinions.

Summary:

1. Is DACOR the manufacturer or is PST the manufacturer?
2. Are these hot-dipped galvanized tanks?
3. Is the beige layer an epoxy layer
4. Is it safe to assume that the tank is galvanized underneath this layer?
5. What kind of blue paint did they use that it came off like skin?
6. Which would be a better (at this point, easier would be nice) route: Try to get the cream tank gray again (by removing the cream layer - assuming it's galvanized underneath...) OR just use a nice white coat of paint to get both tanks matching (appliance white. some rustoleum)

Thanks.

 

[spectrum]

The L nested in a C in the initial hydro date represents Cochran Labs which did the initial testing for PST.

 

[timegan]

Hold on there hoss. First thing is, IF your commited to these tanks....[HYDRO/VIS], maybe a tumble is in order as well. Invest your money and time there. Haven't answered your question/s I know, but the answers could be irrelevant without the "PASS". One step at a time.

 

[Ed Palma]

Yeah, but if they pass, and I paint them, some shop might say that they were tampered with... catch 22.

 

[timegan]

If they pass? Your good. There are really good Zink coatings, plastic, polymer paints, available. AIR dry only. Just tell em (LDS) non heat cured re-paint. Got a couple of 72s myself. They passed...had to tumble em GOOD. Then 4 coates of Varathane liquide plastic, 220 grit sand between coats. Any dive shop Iv'e taken them, am complemeted on the refinnish. All #s clearly visable, hydro, and vis up to date. Nice tanks! From the pics...it looks like the blue tank was pretty well coated. But too late now.

 

[knowone]

Are you tempted to look inside. Hydrochloric will even up ext gal tone.

 

[Ed Palma]

Are you tempted to look inside. Hydrochloric will even up ext gal tone.

Tempted - definitely! Valve's still kinda stuck. Gonna knock it off with a spanner and rubber mallet or a cheater bar. Gonna do it

As for the acid... I think I'll keep the gal tone as is. Then cover it up with flat white. Off to paint em now! Will post in a bit

 

[knowone]

Mr valve and mrs chrome probably don't care anymore since you hogwired them to a piece of f king reo.

 

[Ed Palma]

Mr valve and mrs chrome probably don't care anymore since you hogwired them to a piece of f king reo.

Yeah, you should see the toolmarks! Good thing I'm sticking these tanks into a manifold.

There was some light rust coming out of the tank. Some fleurettes, but generally the insides were smooth. The dip tubes were covered in some verdigris however.

Time for a tumble.

 

[spectrum]

As for the acid... I think I'll keep the gal tone as is. Then cover it up with flat white. Off to paint em now! Will post in a bit

The galvanized patina is a beautiful thing. Nothing you can apply will be more durable or timeless.