An alternative to cork and felt

On Tubenet, there was a discussion on replacing corks and felts with spacers of neoprene or brass, and O-rings. They are supposed to be durable and keep the horn in alignment. Seems like an interesting idea.






Reply #1 - May 25th, 2008,

Neoprene is an incredible material for use on brass instruments! It is all I use for water key cork replacements. It is very consistent compared to cork and much more durable. My only concern with using brass washers, although durable, would-be noise. Felts/corks really serve two purposes: alignment and dampers.


Reply #2 - May 25th, 2008,

I agree. My King helicon had neoprene washers put over the valves/under the caps in '86. They are still in good condition but have always been noticeably clunky. Rubber O-rings might be less noisy as the rubber will have more give than neoprene.


Reply #3 - May 25th, 2008, at 3:37pm

The response to that concern was that the O-ring held it firmly in place. Whether true or not, I don't know.


Reply #4 - May 25th, 2008,

The valve cluster in the picture looks to be from a Conn 20K BBb Sousaphone. I haven't seen a new 20K in some time and it would be interesting to find out what they are using now. Those large valves would really clunk when the felts wore out.



Reply #5 - May 26th, 2008,

Does neoprene have any give? I would shy away from brass, there is a reason the guys who made the horn left space enough for a cork washer.



I do like the O ring idea if it sits out far enough to hit the cap. But since I always carry an extra set of felts, I have never really had a problem. I really like being able to cut the cork to the exact length I need. You could do that with neoprene, and brass could just be filed down to fit.




Reply #6 - May 27th, 2008,

I guess I wasn't thinking so much about the sound from the washer moving around. I would be more concerned about the sound of brass hitting brass such as the finger button hitting the washer. Like Kevin said, if the O-ring were wide enough to stop the valve, that would solve the noise of metal on metal but make the brass washer unnecessary.


Reply #7 - May 28th, 2008,

The brass or neoprene washer was just to bring the alignment up to the correct position. The O-ring was the bumper and held the washer down to the top of the piston.




Reply #8 - Aug 3rd, 2008,

I have some sort of rubber or neoprene water key cork replacements. How do you go about using them.



I mean, do you have to dig out a little concave indent in them, or do you just use them as is. they dont seem to exactly work as is.




Reply #9 - Aug 3rd, 2008,

Some water key assemblies that are sold as replacements sometimes come with rubber corks. I guess they work well enough with those which they are intended, but I think regular cork is easier to use to get a good seal when replacing one.

I wouldn't want to try to cut the face of one to seal, I think you would get an uneven surface. Better to cut the back side to give the face the approximate angle. They will compress a bit.


Reply #10 - Aug 4th, 2008,

I've used soft neoprene and rubber-like corks in water keys with good results.



I've always mounted them, then put in a small piece of sandpaper between the water nipple of the horn with the grit facing the key. Lightly push down on the key while working the paper back and forth, just as you would with hard cork. The horn should be fine

because the back of the paper is the only contact, while the neoprene/rubber will be sanded to match.