Rust (streaks?) in steel tanks

[SquareJ]

Careful with your air compressor. Those things are notorious for having wet or oily air blowing out the hose. Use a full tank or some other clean and dry air for an HP blast.

This is an underrated comment. Home air compressors spit out a "lot" of oil relative to how clean all air needs to be that enters a scuba tank.

 

[stretchthepenn]

So went back to the same shop. Rejected for nitrox for the flash rust. Going elsewhere and going to renew my VIP certification.

 

[wetb4igetinthewater]

View attachment 777227

so I did a bit more search, and found "official" recommendation for cleaning with 5% phosphoric acid, rinse with hot water, then blow dry with compressed air from a cylinder. As soon as I receive the phosphoric acid, I'll redo the cleaning and see if I can avoid all flash rust.

But I'll be taking it to a different shop. It will take a bit to set up a VIP course.

 

[Eric Sedletzky]

@Eric Sedletzky

How do you like my redneck setup? Best I could do on short notice!

View attachment 777121View attachment 777122
Seems to work pretty well. First blast and a bunch of dust came out.

It's not stupid if it works!

I will work on a better long term solution per your advice.

I’m hearing banjo music.

 

[Eric Sedletzky]

This is an underrated comment. Home air compressors spit out a "lot" of oil relative to how clean all air needs to be that enters a scuba tank.

That’s an understatement!
Regular air compressors have no business being used anywhere near the inside of a scuba tank.

 

[wetb4igetinthewater]

I’m hearing banjo music.

Fortunately, I don't have a perdy mouth.

 

[BoltSnap]

have no business being used anywhere near the inside of a scuba tank

Not anywhere near ANY dive related equipment.

 

[Tracy]

Not anywhere near ANY dive related equipment.

My shop compressor is as clean and as dry as any breathing air machine. Not all things are created equally.

 

[TrimixToo]

My shop compressor is as clean and as dry as any breathing air machine. Not all things are created equally.

Do you have an air test that shows that? Just getting low pressure air that dry would be a real challenge.

 

[Tracy]

Do you have an air test that shows that? Just getting low pressure air that dry would be a real challenge.

It gets tested for Grade D breathing air.
My HP compressors have a lower dew point, but it is plenty dry for scuba use.