Leaky Pollard key

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kingrob76
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Leaky Pollard key

Post by kingrob76 »

One of my Pollard water keys has a slow drip. It's not from where it's attached to the horn, but, from the drain opening itself which tells me something isn't consistently seating properly. I've tried adjusting the tension but still get the same results. It's a newish key so it's pretty clean, no gunk in that I can tell (or would expect). This key will be infrequently used Any suggestions on ways to limit the water flow or troubleshoot the exact cause?


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bort2.0
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Re: Leaky Pollard key

Post by bort2.0 »

kingrob76 wrote: Thu Sep 29, 2022 8:13 am One of my Pollard water keys has a slow drip. It's not from where it's attached to the horn, but, from the drain opening itself which tells me something isn't consistently seating properly. I've tried adjusting the tension but still get the same results. It's a newish key so it's pretty clean, no gunk in that I can tell (or would expect). This key will be infrequently used Any suggestions on ways to limit the water flow or troubleshoot the exact cause?
The Pollard website says they're supposed to seat better as they wear in over time. Maybe you just need to use it a bunch to get it broken in? Take the slide off and take it to your desk, and fidget with it during your next Zoom call?
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the elephant
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Re: Leaky Pollard key

Post by the elephant »

I use these. It could be a tiny burr inside due to having been machined improperly. I would contact Jerry about it. He is a nice guy and very accessible. He will likely send you to the trumpet builder who makes these for him. (If it is even the same guy. I really don't know.)

Either one of them might know of an issue where these might leak a bit, and therefore might know of a secret to cure the drip. I think using a Swiss file inside the case might solve it if a burr is present. It could also be a very small bit of solder that got inside when it was assembled. Remember that this is an open or closed system, with no other state possible (unlike the Amado waterkey) so it is either not seating properly due to a tiny bump somewhere in the seat, or too much material was removed from the seat when it was machined. The spring is not part of this system, so far as leaking goes, and adjusting it will not fix the issue. It is only in the seating of the plunger, and that has to be an obstruction of some sort or a genuine leak due to a gap in the seat.
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bloke
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Re: Leaky Pollard key

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Via my connections with NASA, NIST, etc. (as others were born with "perfect pitch" - I was born with "perfect time" - so these folks will contact me - from time-to-time - to check their instruments/equipment/data), I've stepped up my own personal tubas' technology to their nearly flawless technology: which utilizes tight-fitting formed rubber to seal up gaps.

The technology involves a soldered-on nipple - with a plateau-shaped opening - spring action, a short cylindrical piece of rubber, which presses tightly against the plateau-shaped opening, and a control lever. (These work in outer space, as well as in the past, present, and future, which is why their development was a collaborative effort. These devices - occasionally - can end up costing as much as ¥285, and that doesn't even include flying in an RTE "Repair Technical Engineer" to do the installation and adjustments.)

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Last edited by bloke on Thu Sep 29, 2022 9:58 am, edited 1 time in total.
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kingrob76
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Re: Leaky Pollard key

Post by kingrob76 »

I pinged Jerry and will wait to hear what he says, hopefully it's something really simple and minor. I do see it hang up once in a while when I press the button down so that would definitely lend credibility to a burr of some sort. I did not test them prior to install, choosing to leave them safe in the packaging (mostly safe from being lost).
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