Tank tumbleing?

[Linedog]

Long story short. A friend of mine adopted a 3 year old HP steel tank from a diver who neglected it. Now everytime it gets VIPed, it needs a tumble. His other tanks are fine, but he takes very good care of them. What gives?

[fishb0y]

is he storing it empty? It should be fine after it gets tumbled then filled, maybe with a little flash rust.

[boydski]

Long story short. A friend of mine adopted a 3 year old HP steel tank from a diver who neglected it. Now everytime it gets VIPed, it needs a tumble. His other tanks are fine, but he takes very good care of them. What gives?

The vast majority of the rust that I see in steel tanks is the result of filling the tanks without blowing the valve clear of water by cracking the valve open for a few seconds before attaching the fill whip. This is usually obvious by the spattered droplet pattern of the rust in the tank. The DIN valves that are angled up are especially prone to collecting water in them.

If the entire bottom of the tank is covered with heavy rust and scale, it usually means you've been getting wet fills (i.e. the filters are saturated on the compressor and need to be changed), but that is very unusual and would be affecting a lot of customers.

Your friend might also want to check and be sure that the rust has been removed when it does get tumbled. Tank Tumbling can be done using several different methods and some work much better than others but are very labor intensive.

[Dusty2]

I would suggest in addition to tumbling that he have it oxygen cleaned. This will leave a thin coat of protectant on the inside to prevent oxidation.

[Geek]

I would suggest in addition to tumbling that he have it oxygen cleaned. This will leave a thin coat of protectant on the inside to prevent oxidation.

??

Ummm, what is added to the inside of a tank during O2 cleaning?

[renoun]

It could also be that your friend is having his tank viped at a shop with a propensity for tumbling tanks rather than applying critical thinking skills. I would suggest your friend look inside the tanks before he sends them in and request that the shop call him before preforming other work. A shop I'm familiar with had a propensity for tumbling my friends tanks, they wrote "VIP only- call before other service" on the tags when they sent in their tanks, and started getting free tumbles until the shop started paying better attention.

[Linedog]

I'm just scratching my head as to why 2 HP 100's, same manufacturer, same shop doing the fills, same storage location, same dives would need a yearly tumble. If the shop is just trying to generate income I would be more inclined to believe that both tanks would need a tumble
Not the same one for 3 years in a row.

[ArcticDiver]

It could also be that your friend is having his tank viped at a shop with a propensity for tumbling tanks rather than applying critical thinking skills. I would suggest your friend look inside the tanks before he sends them in and request that the shop call him before preforming other work. A shop I'm familiar with had a propensity for tumbling my friends tanks, they wrote "VIP only- call before other service" on the tags when they sent in their tanks, and started getting free tumbles until the shop started paying better attention.

+1

[camerone]

A shop I'm familiar with had a propensity for tumbling my friends tanks, they wrote "VIP only- call before other service" on the tags when they sent in their tanks, and started getting free tumbles until the shop started paying better attention.

Similar story about unnecessary work... I had one new (used) bottle I needed hydro'd a while back, and didn't have time to take to the hydro facility myself...so I took them to an LDS chain locally for a hydro... and explicitly wrote "hydro only - no VIP" on the tags.

Got them back replete with inspection stickers, a VIP charge, full of air, etc. Nothing irritates me more than people too stupid to follow extremely clear directions...except maybe having to scrape stickers off of tanks. So they hit two hot buttons of mine at once, which pretty much opened up the wrath of unhappy-and-seriously-pissed-off me, and that's not fun to be around.

I made them scrape every sticker (shop, VIP, etc) off the tank themselves, even though when they noticed the service tag after having it pointed out they said, "well, we'll throw in the VIP and fill for free, and you need the sticker anyway. We do them as a matter of policy." I don't need the sticker. I need to clean and rebuild that valve, anyway. I don't give a rat's ass about shop "policy" - that's their problem for accepting the business, not mine once they've accepted the service contract. I don't want the air fill in a tank that I'm intending to clean myself and use for oxygen. I'll do my own VIPs, thank you.

Somewhere, we stopped teaching kids to read in school

Ummm, what is added to the inside of a tank during O2 cleaning?

Nothing, necessarily.

O2 cleaning involves a dilute degreasing solution (Blue Gold, Crystal Simple Green, etc), and agitation. This may be combined with tumbling (ceramic or glass beads, usually). Following the cleaning stage, the tank is rinsed with clean water and dried. A little flash rust is harmless. I've never had a problem with it using a hot water rinse and immediate drying with very dry air.

Steel tanks have a propensity to develop flash rust after the rinse step (and often after a hydro, too, since that involves filling with water.) This can usually be averted by rinsing with hot water, and immediately drying with very dry air - scuba air actually works well since its dew point is super low.

Some places instead use a cold water rinse and an O2 compatible rust inhibitor in the rinse water. Global makes one they call "Compound O". It works really well, from what I've seen, but I don't think it's totally necessary.

[BASSMAN]

I almost tumbled my own tank and myself, getting out at Jorsted creek! That's one steep hill!
Now back to your original topic...