Corrosion on metal reg parts... how much is too much?

[fjpatrum]

I finally started cleaning the old regs I bought last spring. Well, the second stages anyway. I am awaiting a couple of helpful tools and working out parts lists before I get to the first stages. As I was saying, the second stages got a bath today. The Swimaster was actually in much better shape than I expected. Diaphragm is in good shape, not much corrosion interior or exterior and everything seems to be working well. Not the best tasting thing I've ever had in my mouth, but seems functional at this point. The Dacor Pacer, on the other hand, was worse than I originally thought. This thing looks like it didn't get a good rinse after its last saltwater bath. Heavy corrosion inside and the exhaust valves were so dried out that they had glued themselves to the metal of the reg. I hadn't expect the soft rubber in either unit to be still good so no harm there, really. The diaphragm on the Dacor has two small tears in it so that will have to be replaced.

My big concern is the corrosion. As you can see from the pictures the 6 minutes I dunked the unit in the sonic cleaner and 20 minutes or so after that with a soft toothbrush really made a world of difference. There is still a bit of corrosion left, however, and I am wondering if I should hit that with some sand paper to make sure it's all gone or not stress over it. I'm not too concerned with exterior stuff as that's mostly cosmetic, but breathing corroded metal isn't exactly what I consider a great idea.

Any insight from you more experienced folks? Get it all gone or don't worry?

 

[halocline]

I would just clean all the verdigris off and make sure there's no flaking metal. The loss of plating on the sealing surface for the exhaust valve might mean a bit of seepage there, which I suppose would make the reg breathe a little wet while inverted...with double exhaust valves I wouldn't doubt that it did that to begin with.

Other than that I wouldn't worry too much about it, I've seen way worse.

 

[dumpsterDiver]

Sand paper??? No Way.. Maybe a steel wool super gently or maybe a scotch brite pad gently... but it looks to be in fine condition. I would very gently polish the end of the bolt thing.. the sharp edge that goes to the seat. That and the exhaust valve areas are the only areas were a little corrosion may matter (and they look fine to me) . I use a good bit of grease on the scew that secures the ring on the second stage as well as the threaded bolt, whatever the hell it is called.

That is the reg I've used on my pony bottle for 10-15 years and it is dented and works fine.

 

[Mr Carcharodon]

Try 50% white vinegar and 50% hot water (about 120 F) and a dash of simple green. The acetic acid in the vinegar will take care of of most of the corrosion. Don't leave it in the bath for more than about 5-10 minutes since acid will get through holes in the chrome plating and attack the base metal. You want in in there just long enough to get the corrosion off. Some plating defects around sharp features like threads is to expected. And while you can remove the copper oxide it will return quickly.

Sandpaper has real potenial to make things worse instead of better. I'd proceed cautiously with that.

 

[Zung]

Yeah, vinager, then rinse well, then maybe a bit of Brasso (brass polish fluid) to finish it off.

I have a MK20 or 2 with a few patches of brass showing up inside the cap, where the crown of the piston rides. After the above treatment, it seals OK, no leak whatsoever.

 

[herman]

I'm with the rest, don't sweat it, that reg looks darn near new compaired to some I have done. A 50/50 vinegar bath followed by a toothpast scrub and let it go. I would not use steel wool, too much chance for slivers to remain, Scotchbright is better and that just on the mating surfaces where seal is important. I prefer the look of battle scar missing chrome as opposed to sanded spots with more missing chrome so I would leave the outside as is.

 

[fjpatrum]

Thanks, everyone. My vinegar solution was about 10% but worked quite well. I ended up leaving the Swimaster in the solution much longer than I intended but it got a good rinse after the fact. I'll leave both as is (which was my original instinct) and not worry about the remaining blemishes. Now for the real fun... the first stages. I'm sure I'll be back with more questions soon.