Possible red rot?

[Jim2195]

I bought a used King 606 trombone around three days ago. It’s in relatively good condition with a few scratches here and there, and two small dents on the bell along with one dent on the tuning slide. Yesterday I’ve started to notice that there were pink-brown colored “corrosion spots” on the bell area, near the dents. (it looks like corrosion to me, I’m not sure) The corrosion there does not extend to the inside of the bell, but inside the bell there also is a tiny bit of the corrosion, but in a different location of the bell. There is also a small amount of this pinkish brown stuff on the lead pipe and some on the end of the outer slide, around the water key. I am suspecting that this can possibly be red rot, although I have heard that red rot has dark spots in the middle of pink-red circular shaped splotches, and this corrosion doesn’t seem to have dark spots nor are the "spots" circular. I have also heard that red rot comes from moisture or from acidic conditions, and the trombone has not come in contact with water since I got it. However I am nowhere close to an expert so I am reaching out to this forum for answers. I want to know if this “corrosion” is truly red rot, if there is anything I can do to stop the presumed red rot, or what I can do to prevent it from spreading further.

[Jim2195]

I have some more pictures here. For some reason I was not able to post them in the main post. I apologize if these pictures aren’t good. My phone camera is not the greatest.

[Elow]

It’s looks like some raw brass that got left in chemicals too long to me. I think it’s too pink to be red rot, but i’m no tech.

[tbonesullivan]

Red Rot usually only happens where water can rest for a long time, such as the end bow of the slide. The pink spots with dark centers on the end bow could definitely be red rot.

The area near the hand slide grip looks like acid bleed. The areas on bells look like either acid bleed, or just missing lacquer which has oxidized. Brass is an alloy so it can oxidize into several different colors, one of which is red / pink, or even orange.

[BGuttman]

One thing: red rot comes from the inside out. If you polish the stain and it's not red ot it will eventually disappear.

Red rot takes a while to develop, so I don't expect it on newer horns, except if they have been mistreated with an acid bath.

[Jim2195]

One thing: red rot comes from the inside out. If you polish the stain and it's not red ot it will eventually disappear.

Red rot takes a while to develop, so I don't expect it on newer horns, except if they have been mistreated with an acid bath.

Thanks for informing me. I don’t know how old my trombone is. All I see is a King 606 in relatively good condition,. Also, how can I polish the stain?

[Jim2195]

Red Rot usually only happens where water can rest for a long time, such as the end bow of the slide. The pink spots with dark centers on the end bow could definitely be red rot.

The area near the hand slide grip looks like acid bleed. The areas on bells look like either acid bleed, or just missing lacquer which has oxidized. Brass is an alloy so it can oxidize into several different colors, one of which is red / pink, or even orange.

Thank you for helping. I do not know if the pictures make it look like there are dark centers on the pink spots at the end bow of the slide, because as far as I can see, I don’t see any dark centers. However I have no experience whatsoever regarding red rot, so I will assume there is a possibility. Do you know if there is anything I can do about it if it is actually red rot?

[Jim2195]

It’s looks like some raw brass that got left in chemicals too long to me. I think it’s too pink to be red rot, but i’m no tech.

Thanks for helping. Do you know if there’s a way to check if it’s red rot or just raw brass?

[Elow]

It’s looks like some raw brass that got left in chemicals too long to me. I think it’s too pink to be red rot, but i’m no tech.

Thanks for helping. Do you know if there’s a way to check if it’s red rot or just raw brass?

I would try to buff it, but you might not be able to do that. I’ve heard wrights brass polish works well, not sure if it’s as effective though.

[tbonesullivan]

Thank you for helping. I do not know if the pictures make it look like there are dark centers on the pink spots at the end bow of the slide, because as far as I can see, I don’t see any dark centers. However I have no experience whatsoever regarding red rot, so I will assume there is a possibility. Do you know if there is anything I can do about it if it is actually red rot?

Either way, I would just ignore it until it becomes a problem. If it is red rot, there is no way to really stop it once it has gotten all the way through. If it stays the size it is, it shouldn't be a problem unless you dent that part, which could cause it to crack.

The only solution then is to replace the end bow.

[greenbean]

The slide crook spots might be red rot. But does it matter? If it is red rot, it might start to leak in about 20 years. You probably won't be the owner when that happens.

[Jim2195]

The slide crook spots might be red rot. But does it matter? If it is red rot, it might start to leak in about 20 years. You probably won't be the owner when that happens.

That’s a relief. Hopefully that’s the case.