New tank rust

[captain]

I have 40+ years with PST steel tanks. In fact I still use a 47 year PST 72. What ChrisA said is right on. You can tumble them until they look like chrome but in a short time they will have light surface rust. No air is ever moisture free, it's would be impossibly expensive to make moisture free air with an air compressor and filters. You will always end up with 100 or 200 or more PPM of water. The closest you could get to moisture free air would be to partial pressure blend commercial oxygen and nitrogen. Commercial oxygen and nitrogen is less usually than 2 ppm moisture.

 

[fugu]

Hey guys. Ok, I just attempted to O2 clean my PST HP 100's and found some rust. Not flakes, just the brown/orange tinge when I wiped out the inside of the necks with a rag. The tanks are only about a year old by the way.

So, there must be some kind of rust inhibitor that's 02 compatible and safe to breath. Probably something you can get at Canadian Tire, Rona or Walmart.
Does anyone know of something like that?

I dont think sending the tanks back because of a little rust is nessisary. Like the other guy said, there is always going to be moisture and steel rusts. Just try to keep it to a minimum.

cheers,
Clay

 

[Web Monkey]

If they're new, take them back and have them serviced (should have been done before you got them).

If they're used, get them serviced (tumbled/cleaned), especially if you're going to be using Nitrox.

I understand that some tank brands rust almost immediately, however tha doesn't mean you should be diving with them rusty.

Terry

Just received 2 E8-119 tanks. Both have some rust inside, not a lot but clearly visible.

What is best course? I could ship them back, but if there is an easy fix I'd like to do it. Is it common to get a little rust in newly delivered tanks?

 

[DA Aquamaster]

A thin dusting of flash rust is entirely normal and is not a contra-indication for service.

If, as indicated above, it starts to form flakes or spots it should be removed through tumbling. The concern here is that a heavy flake or spot of rust could be starting to form a pit or obscuring a rust pit.

In less serious cases the inside of the tank can often be wire brushed to successfully remove the excess rust.

If a Faber selling LDS VIP'ed the tanks and suggested you should return flash rusted PST tanks, I suspect it had a lot more to do with you buying PST rather than Faber tanks. Returning the tanks is ok I guess, but how exactly do you plan to handle it when the replacement tanks arrive with a normal amount of flash rust and you try to get them VIP'ed at the same shop?

 

[Web Monkey]

PST tanks, I suspect it had a lot more to do with you buying PST rather than Faber tanks. Returning the tanks is ok I guess, but how exactly do you plan to handle it when the replacement tanks arrive with a normal amount of flash rust and you try to get them VIP'ed at the same shop?

The Faber tanks are coated on the inside and shouldn't come with rust.

Terry

 

[derwoodwithasherwood]

So, there must be some kind of rust inhibitor that's 02 compatible and safe to breath. Probably something you can get at Canadian Tire, Rona or Walmart.
Does anyone know of something like that?

Interesting idea. Autobody shops carry a few variations of "Rust Converter". The simplest is a mixture of phosphoric acid (that's the stuff in Coke that cleans rusty nails) acetic acid (the stuff that gives vinegar it's odour) and manganese carbonate. It reacts chemically with rust turning it into a hard, black and inert paintable coating. Other variations add things like tannic acid (tea), vinyl acrylic resin, latex or metal powder forming a sealant to prevent further contact with air and water.

I'd be a bit nervous of using anything with a vinyl component (because of possible off-gassing) but I bet one of the simpler concoctions would work nicely.