JackD

Ok, this may sound very stupid, but what exactly do valve caps do? Why not just seal off the bottom of the valve casing? What's that hole for? I know trumpets play without caps on at all, so what exactly are they for?

Robert Rowe

Among other things, the caps keep the oil / sputum build-up from capriciously dripping on you and your clothes. They keep dirt out; they remove (unscrew) to allow access to the casing tube for maintenance, repairs, cleaning, etc. They do have that "weep hole" that does leak somewhat, but their presence helps contain the oil / sputum mixture to assist in moving "down-stream" towards evacuation via a water key. I believe the "weep hole" provides venting, as well -- I'm not sure, but this may help prevent a partial vacuum from forming inside the valve casing tube.
Just a few thoughts ....


Regards,
Robert Rowe

Gilligan

If you look at the older vintage valve bottom caps you will see that the holes in the bottom all had a short extension (weeping) port. This was to direct the spittle down out of the valve bottom without spraying onto clothes. The older vintage valves didn't have the air tight tolerances of todays horns.

With todays horns the bottom valve caps provide protection from dirt and the hole prevents a vacuum from forming and slowing the return of the valve. With the tighter tolerences of todys instruments a hole for drainage is no longer needed as most of the moisture exits through the water keys or out the bell.

trumpetgirl612

so what, then does the difference in weight of the valve caps make?

iguananaught

Trumpetgirl,
there is a lot of discussion about the weighted valve cap issue. Some say that the extra weight makes no difference, others think there is a big difference. When I had heavy caps on my horn, I found the slotting to be more even, and the response to be a bit better. It seemed that the horn may have sounded a bit darker as well. The added weight takes away some of the vibration in the valve casing, which may or may not make any difference. I don't think I could have been any more wishy-washy in that answer. Have a nice day,

patrick

trumpetgirl612

thnx man, idk i have heavy caps on my student horn. if they fit my pro horn ill put em on and see if i feel a difference i guess
thnx
Emily

Adrian_H

I bought a set of Curry XXX heavyweight caps for my Bach ML43 a while back to experiment with.

They really changed the feel of the horn, but unfortunatley, the changed the feel for the worse for me.

With the XXX Caps on, the horn become incredibly stuffy, I lost about a fourth off my upper range, the slots became way too tight, there was no play for bending/tweaking notes.

In conclusion, for me and my instrument, they were awful - however, one good thing was, that because of the weak dollar and the fact that I imported them from the US (I'm in the UK) I sold them on Ebay for more than they cost to buy! So in the end a wise investment!!!