Benefits of painted Faber steel tanks?

[sunny_diver]

What benefits do painted Faber steel tanks have over hot dipped galvanized ones?

I once heard that HDG tanks rarely fail hydro because of the pre-stretching procedure. It seems that painted tanks could be safer since a flaw wouldn't be masked by that procedure. In other words, painted tanks could fail hydro when they should vs. HDG tanks which pass hydro when they shouldn't.

Sometimes I wonder if HDG is offered because that's what the market wants, but manufacturers think painted is better.

I wish I could call Faber to ask, but they don't seem to be easily reachable.

 

[rhwestfall]

Painted is cheaper, and probably easier in regulatory compliance, but suck....

 

[Divin'Papaw]

The pre-stretching procedure doesn't mask defects. It is the manufacturer required procedure and is completely legit. Worthington requires the same. It is not "rigging the system" but is required to actually prevent unnecessary failures, not to hide an issue that could be there.

As to the benefits of painted over HDG? None that I can see. I have always preferred HDG. I currently own 4 Worthington and 2 Faber HDG tanks. Far superior to painted, especially in salt water, IMO.

 

[PEDiver]

Galvanized tanks are usually heavier than painted steels. I much prefer painted steels in SM configuration since I feel the buoyancy characteristics are better. In BM configuration it doesn't really matter as much to me and I have used both. I would not be concerned about which one is "safer" - they are both manufactured according to standards and I've never heard of any issues with one or the other failing due to being painted or HDG. The paint will flake and scratch over time which some people don't like for cosmetic reasons, but aesthetics is the last thing I am worried about in my diving.

 

[Tracy]

What benefits do painted Faber steel tanks have over hot dipped galvanized ones?

I once heard that HDG tanks rarely fail hydro because of the pre-stretching procedure. It seems that painted tanks could be safer since a flaw wouldn't be masked by that procedure. In other words, painted tanks could fail hydro when they should vs. HDG tanks which pass hydro when they shouldn't.

Sometimes I wonder if HDG is offered because that's what the market wants, but manufacturers think painted is better.

I wish I could call Faber to ask, but they don't seem to be easily reachable.

You seem to be confused about the hydro aspect.
Neither painted nor galvanized have any effect on the tank passing or failing hydro. The pre stretch is done to soften up the galvanizing to allow the tank to be tested accurately. It isn't needed on 99% of them. It was an issue that presented on the old Worthington galvanized tanks with their very thick and heavy galvanizing. Usually during the first hydro, if the tank had a nice soft life and was never abused, the galv coating was still thick and would present as brittle. This would show the tank as a fail, not the other way around. If you immediately retested the tank, it would pass on the second attempt if the tank itself was good.
It doesn't really come into play with the fabers, their galv coating is much thinner and lighter. They put it out there in writing to cover their bases in case one does fail prematurely but it isn't usually ever an issue with a Faber.

 

[Bearded Diver]

Galvanized tanks are usually heavier than painted steels. I much prefer painted steels in SM configuration since I feel the buoyancy characteristics are better. In BM configuration it doesn't really matter as much to me and I have used both. I would not be concerned about which one is "safer" - they are both manufactured according to standards and I've never heard of any issues with one or the other failing due to being painted or HDG. The paint will flake and scratch over time which some people don't like for cosmetic reasons, but aesthetics is the last thing I am worried about in my diving.

I’ve only handled one HDG tank, 120 PST and I was curious how much extra weight the process adds vs the painted tanks. Thanks in advance.

 

[rjack321]

I’ve only handled one HDG tank, 120 PST and I was curious how much extra weight the process adds vs the painted tanks. Thanks in advance.

The zinc is micrometers thin, comparable (or even thinner) than the spray galvanizing on the painted version. You'd need to do some sort of statistical test and measure hundreds of tanks to discern if HDG and painted were 2grams different on average or whatever. There is more manufacturing variability in the steel itself than in the coating weights.

Bottom line from a practical scuba weighting perspective, none.

 

[andrespp]

What benefits do painted Faber steel tanks have over hot dipped galvanized ones?

I once heard that HDG tanks rarely fail hydro because of the pre-stretching procedure. It seems that painted tanks could be safer since a flaw wouldn't be masked by that procedure. In other words, painted tanks could fail hydro when they should vs. HDG tanks which pass hydro when they shouldn't.

Sometimes I wonder if HDG is offered because that's what the market wants, but manufacturers think painted is better.

I wish I could call Faber to ask, but they don't seem to be easily reachable.

I am not familiar with HDG tanks, but have quite a number of Fabers.

As long as the coating is protected from scratching and other stuff with a net, and the interior has no oil/water etc, their lifespan is quite long. One of my faber was manufactured in 1988, and passes hydro and visuals w/o problems. Sometimes the rust inside looks a bit ugly, so I put them in a tumbler for a couple hours and that´s it.

Thank God, nowadays most of the tank inspection companies in my area do not engrave by punching the inspection date in the tank shoulder, but use stickers or tags. Punching was terrible for the coating in that spot.

 

[andrespp]

Painted is cheaper, and probably easier in regulatory compliance, but suck....

I do not think it is cheaper, as the Faber typical coating is a three steps process: a zinc galvanizing spray, followed by an epoxy paint and then a top coat of polyurethane.

The main adventage of the HDG I can think of, is that aside the mechanical protection to the steel, the zinc acts as a sacrificial anode, preventing rust to occur. Maybe that the galvanizing is much harder to damage that the Faber coating, have seen cave divers using HDG tanks without protective nets, so...

 

[rhwestfall]

I do not think it is cheaper, as the Faber typical coating is a three steps process: a zinc galvanizing spray, followed by an epoxy paint and then a top coat of polyurethane.

Regulatory compliance for that process is likely costlier than paint...