How screwed am I?

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Diego A. Stine
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How screwed am I?

Post by Diego A. Stine »

I recently purchased a pt-6 made in 1992, so it's a lovely handmade example that sounds wonderful and is very in tune. The only issue is that due to either it's age, assembly, or something else, the valves leak (mostly 3+4). Anyone have ideas for a temporary "fix", or is this a $$$$ job? How do tubas get to this point?

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Diego Stine
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LeMark
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Re: How screwed am I?

Post by LeMark »

I think the leak can be stopped fairly easily by a skilled repairman, but it would be just a patch.

long term, the valves could be replaced
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bloke
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Re: How screwed am I?

Post by bloke »

Are you saying that they leak where the knuckles are supposed to be brazed into the casings?

If that's all it is, I would just take a dental pick, scratch out where there is separation - to get it really clean, and just float some lead solder in there. That should way outlast your own lifetime.

Assuming the same, a hillbilly fix would be with epoxy glue, but I think that would be a damn shame.

The better the person you take it to is at painting with heat, the neater the job will be.
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MiBrassFS
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Re: How screwed am I?

Post by MiBrassFS »

You’re not screwed at all. Simple fix by a capable brass repair person. Avoid doing anything (no glue, caulk, chewing gum) but allowing that person to correctly soldering the areas. Good luck.
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bloke
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Re: How screwed am I?

Post by bloke »

If there's lacquer on those two valve casings, it would be a good idea to get it off first, because - since it's thicker brass - it's going to take more heat than just soldering tubing together, and even epoxy lacquer could end up burning... maybe. You can't buy paint stripper worth a crap anymore in the store, but real repair guys can buy it, and we know where to buy it. Anyway, I already posted and told you that this can be done and it's not hard for someone who is skilled, but now I'm just additionally suggesting that you might consider stripping the lacquer off of those two valve casings (at least the portions of them that are going to be heated a lot) prior to doing this, and it's probably going to be your repair guy who's going to strip the lacquer off of those casings, unless you or your dad has saved back some paint stripper from a decade ago and it's still in good shape.

This post only has to do with cosmetics, and is only an addendum to my previous response. Everyone says, "I only care about the sound", but I call bullsh!t on everybody.

... going off on a bit of a tangent, band directors who tell me they don't care about having the dents removed from instruments that their young scholars have torn up (because they're trying to save money) are just asking their young scholars to tear them right back up again, because there's no motivation to try to keep something nice if it's already not nice.
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Mary Ann
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Re: How screwed am I?

Post by Mary Ann »

I'll be thrown off the board for this, but I have fixed many a thing with good metal tape, which ends up air tight. Way better than caulk, as long as it can be made to fit over the hole. And totally removable.
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bloke
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Re: How screwed am I?

Post by bloke »

One of my instruments has some vent holes that were drilled into it at imbecilically wrong places. Miraculously, the spots where they were drilled did no harm. (The previous owner told me who drilled those holes. The person who reportedltly drilled them has a reputation, and I'm not going to sully it.) I've been considering taking the valves out, filling those holes with epoxy, and then coloring them with brass colored paint. Ie. Mary Ann isn't off track at all. :thumbsup:

Something that I've been thinking about those rotors - since this thread started - is that they may be perfectly fine on the insides, but simply the brazing material didn't get pooled up all the way to the outside of the knuckles. Just like my stupid vent holes, the fact that those brazing joints weren't filled all the way to the outside makes no difference at all if they are sealed on the inside...(assuming my guess is correct...??)

...Next, someone is going to suggest some particular brand of valve oil. :laugh:
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MiBrassFS
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Re: How screwed am I?

Post by MiBrassFS »

Someone vented the rotors on one of my tubas years ago. They had a way of putting felt over the holes (they called it a “mustache…”) to prevent a puff of air (or something to that effect) when playing. I decided I didn’t care for the whole thing, so I soldered the holes back closed. No harm, no foul. Just not for me. The location of the hole is (of course…) critical as is (of course…) the condition of the valves to begin with.
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