I m Tired of Cleaning Rust Off...

[sandyeggoxj]

My stout kettles. I have f#$@ed up tig welding stainless before. I know how easy it is to cook the chromium right out. But this is ridiculous. Somewhere in the neighborhood of 50% of the ferrules welded suck. Plus there is tooling marks from non-stainless tooling that keep rusting on me. The inside of the handle on the BK is all sugared. It was polished to try and remove that, but it is still there. Or welds inside fittings that didn't quite penetrate fully before interior polishing so there is a crack that rusts inside the crack. I know they are made in China but I thought that a couple grand would get me something that didn't rust.

 

[GilaMinumBeer]

My stout kettles. I have f#$@ed up tig welding stainless before. I know how easy it is to cook the chromium right out. But this is ridiculous. Somewhere in the neighborhood of 50% of the ferrules welded suck. Plus there is tooling marks from non-stainless tooling that keep rusting on me. The inside of the handle on the BK is all sugared. It was polished to try and remove that, but it is still there. Or welds inside fittings that didn't quite penetrate fully before interior polishing so there is a crack that rusts inside the crack. I know they are made in China but I thought that a couple grand would get me something that didn't rust.

Try chemically passivating tham with five star acid number 5.

 

[sandyeggoxj]

I'll do that. I passivated them with BKF like stout told me to do when I got them. I clean them with BKF regularly. I only use a sponge. Nothing abrasive. And I keep using that sponge to wipe rust off the same spots.

 

[GilaMinumBeer]

I'll do that. I passivated them with BKF like stout told me to do when I got them. I clean them with BKF regularly. I only use a sponge. Nothing abrasive. And I keep using that sponge to wipe rust off the same spots.

I would soak them with phosphoric acid to stop.the rust in its tracks. And follow that with acid 5 to deeply passivate the steel.

 

[orangehero]

Acid 5 is a blend of phosphoric and nitric acid.

A safer alternative is to use a 10% w/v citric acid solution or 5% w/v citric acid and 5% w/v ascorbic acid. Heat it up to about 160°F and recirculate overnight or until it's back to room temp. Repeat as necessary.

BKF is abrasive, so I'd keep hitting it with that too after every brew.

 

[GilaMinumBeer]

Acid 5 is a blend of phosphoric and nitric acid.

A safer alternative is to use a 10% w/v citric acid solution or 5% w/v citric acid and 5% w/v ascorbic acid. Heat it up to about 160°F and recirculate overnight or until it's back to room temp. Repeat as necessary.

BKF is abrasive, so I'd keep hitting it with that too after every brew.

Yes. However the straight phos will more quickly convert the rust to black oxide. Leaving the blend to focus zolely on passivation.

 

[sandyeggoxj]

Well I have a couple gallons of acid 5 hanging around. Should I circulate it hot? Also, how do I do the outside of the kettles?

 

[GilaMinumBeer]

Well I have a couple gallons of acid 5 hanging around. Should I circulate it hot? Also, how do I do the outside of the kettles?

If I recall correctly, yes. It should be hot. Five star is the best resource there. I used to have a chart and recall temps near 170. But I suggest you call them and talk to a chemist about your specific issue.

 

[sandyeggoxj]

Will do. Five star is always very reaponsive. Not sure if I'll have time during biz hours tomorrow but I plan to call stout too.

 

[Bensiff]

Agreed on the quality of the welds. I have the same issues but they are not as bad as yours sound.

 

[orangehero]

Well I have a couple gallons of acid 5 hanging around. Should I circulate it hot? Also, how do I do the outside of the kettles?

If you have silicone in your brewery you should be careful with phosphoric and nitric acid as they each can quickly degrade it, especially at high temps. If you do use it I would try to keep contact as short as possible. On the other hand citric acid is safe in that regard as well.

 

[sandyeggoxj]

Good to know about silicone. Most of my TC gaskets are the teflon type hard gaskets but I do have a few silicone here and there. The sight glasses don't line up so I use a silicone at the bottom to seal even when it is out of alignment a bit.