TromboneChat

Just did my yearly homebrew chem clean on my greenhoe tenor. I used to take it to a tech, but I don't really trust the remaining local techs to carefully disassemble this valve...

This is what it looked like. Last year was the same. I'm always taken aback by just how bad this horn seems to get inside. What could be causing it? Is this normal? I'd expect this amount of horrible junk after a decade, but this has been less than a calendar year of regular oiling and very good oral hygiene.



There's so much scale that builds up on this valve that it's a struggle to get it out of the casing. I'm sure the fact that the valve core and case are not tapered doesn't help, either.

What oil do you use?

Ultra pure.

The amount of scale that builds up depends on a few factors: the pH of the player, amount of use, how it is stored when not in use, etc….

I have seen horns that get like your image in 3 or 4 months. Others take years. For your situation, just remember that the scale is not just in the valve….it is throughout the horn. Thus, make sure you do a chemical clean or ultrasonic clean regularly. Swabbing will not remove it.

What are you using to clean it with?

Limescale can only be removed by an acidic solution. Detergent does not dissolve it. Detergents remove grease and organic matter only. Oxidation, which is the dark brown discoloration on the rotor, is also removed with acid.

Having said that, you have to ensure that any acid used to clean is correctly neutralized, or, you will end up with deposits forming much more rapidly, due to the surface of the material being "unstable". (That isn't the technical term, but it is easily understood)

I use white vinegar and then thoroughly wash with dishwashing detergent to neutralize.

Maybe it’s worth soaking in a dishsoap solution for a while to ensure the vinegar is fully neutralised?

Dish soap isn't very alkaline and won't neutralize the vinegar. Baking soda is much better as a neutralizer for the vinegar. You won't need much. Maybe add 2 tablespoons to your dish soap solution. Remember to rinse well.

Bruce, what about sodium carbonate - Arm & Hammer Washing Soda - as a neutralizer?

Sodium carbonate is even more effective. One tablespoon to the dishwashing liquid. It's just that more people have baking soda than washing soda, so that's why I recommend it.

I didn't clean mine until it stopped working well, which was more than ten years of playing. (At the time i didn't know how to disassemble, so i waited until I had to.)

It didn't look anywhere near as bad as that. That looks like more than scale to me, do you by chance eat while playing? If not, then I think you just have a body chemistry that does that, so maybe lubricate more heavily and more often, and clean more often.

I'm very fastidious about flossing and brushing my teeth before I play. Maybe I'll have to experiment with different valve oils.

Re. using dish soap - which I would imagine is the equivalent of what we call 'washing up liquid / detergent' in Britain. May I suggest that you check the ingredients in dish soap before use, as the stuff we use over here has a lot of salt added to it? Reason is that pure detergent is as runny as water, housewives prefer it to be thick, and salt is the cheapest way for the makers to thicken it up - with the added bonus of reducing the surface tension of the water when you wash dishes.

A friend of mine used to use washing up liquid in his car's windscreen washers, and couldn't figure out why his windscreen was always smeary. I licked my finger, wiped it on his windscreen, tasted it, and said "Pat - those smears are salt!" After he switched to using proper windscreen washer fluid, no more smears.

HTH, and best regards,
Jack

PS - that's also the reason why I never use washing up liquid to wash my beer glasses - only warm / hot water.

Actually it's not salt, but more likely a sodium phosphate (often sodium tri polyphosphate or tetra sodium pyrophosphate). In the US we use high viscosity polyoxyethylenes, which thicken the soap but remain free-rinsing.