Rust in steel tank

[rob.mwpropane]

Here's a different take on using chemicals to do the job.

O2-Safe Rust Inhibitor for Steel Tanks

So I'm planning on tumbling and cleaning my OMS/Faber LP85s. I've been looking at using rust inhibitor, but I don't really want to spend the $50+ and shipping to get a gallon of Compound O (Diethanolamine/DEA/DEOA). Looking for alternatives, I came across Evapo-Rust and also Cocamide DEA...

scubaboard.com

 

[tbone1004]

Thanks Tom. Now does rust tend to occur on the bottom? Is it possible to have a small wheel brush (that will fit inside the cylinder opening) or is that just impractical and better to do tumbling?

the brush included gets into 3/4" necks, not 7/8"

 

[wetb4igetinthewater]

the brush included gets into 3/4" necks, not 7/8"

Do you mean the other way around? As 3/4 is 0.75 and 7/8 is 0.875.

 

[Walde]

Does the whipping leave some "dust" in the tank and if so, what is the best way to clean it?

 

[boulderjohn]

Cylinder Quick Whip Kit

Cylinder Quick Whip Kit

www.scubatools.com

same as this one, just has a short and long rod.

View attachment 763674

I have this apparatus, and in my experience, the parts that are supposed to clean the tank walls are useless. Another form of a whip has loose steel cables, like a cat-o' none tails. I have never seen one of them at work.

 

[Tracy]

Do you mean the other way around? As 3/4 is 0.75 and 7/8 is 0.875.

No, he meant what he said. 7/8 valves are smaller than 3/4.

It is 7/8 UNF vs 3/4 NPS.

 

[rob.mwpropane]

Do you mean the other way around? As 3/4 is 0.75 and 7/8 is 0.875.

3/4" NPS vs 7/8" UNF

Edit: Tracy beat me to it.

I have mostly 7/8" which is why I posted the chemical way earlier... too much of a pain trying to get something in there and still protect the threads.

 

[boulderjohn]

I believe the primary reason for rust on the bottom has to do with cleaning the tanks. In one case I saw, it was obvious that the person doing the cleaning did a great job cleaning and drying the tank, and then put on a valve that had been cleaned but not so thoroughly dried. The rust came from water dripping from the valve.

 

[tbone1004]

Do you mean the other way around? As 3/4 is 0.75 and 7/8 is 0.875.

nope. 7/8 UNF is smaller than 3/4 NPS

Does the whipping leave some "dust" in the tank and if so, what is the best way to clean it?

yes, you can usually blow it out with HP air or rinse it out with scalding hot water then blow it out depending on how bad it is.

I have this apparatus, and in my experience, the parts that are supposed to clean the tank walls are useless. Another form of a whip has loose steel cables, like a cat-o' none tails. I have never seen one of the at work.

I like the brillo's for flash rust and for use in aluminum tanks if they get spots. Since it has the bit for the brush on the bottom I find myself using it for the bottom primarily and whatever I get from the brillo on the sides is more of a bonus.

This one is for steel tanks only and is the whip John was talking about. This gets serious stuff off of the walls but obviously doesn't have the bottom brush so wouldn't do anything for the OP's issue.
Crazy John does have dedicated bottom brushes in this link below but they don't have the brillo pads and it's one of those "nice to have" kind of things.

I believe the primary reason for rust on the bottom has to do with cleaning the tanks. In one case I saw, it was obvious that the person doing the cleaning did a great job cleaning and drying the tank, and then put on a valve that had been cleaned but not so thoroughly dried. The rust came from water dripping from the valve.

fact, when cleaning valves I find it is ideal to hook them up to a transfill whip and blow them through before I put them on a tank.

 

[wetb4igetinthewater]

No, he meant what he said. 7/8 valves are smaller than 3/4.

It is 7/8 UNF vs 3/4 NPS.

And others,

You all can appreciate the source of confusion I hope. LOL.