Valve issue. About to go crazy!

[euphomate]

Against the better half's advice I bought a brand new chinese manufactured four valve euphonium, bought at a closing down sale for 30% of it's original retail price (which was $3000). It looks to be well put together, and made under licence for B&S as their intermediate line. It plays nicely, intonation good, slides move freely, threaded parts fit well. However, the first and second piston valves drag a little when the instrument is played. I can't reproduce the drag by twiddling the valves up and down while just holding the horn, everything goes beautifully. It is only when I blow the thing that the drag cuts in. I have washed out the horn, hand lapped and polished the valves, checked that the plastic valve guides are not damaged, burred, misaligned or jam on the valve guide slots. The valve guide slots themselves look in perfect condition. I have tried both synthetic and non-synthetic oils. The supplied valve springs have good rebound tension. I cannot feel any uneveness or drag when moving or rotating the piston inside the casings with springs and bottom caps removed. If anything is "out of round" it's not obvious. But something is catching in the valve action when I play the thing, and I'm fresh out of ideas. The store has closed so I can't take it back or look for warranty protection. I took that risk when I accepted a 70% discount. Playing the horn with my fingers at different angles and positions on the buttons doesn't make any difference either. The valve venting is clear. Anything I haven't thought of? You might just save my sanity and my marriage.

[Wyvern]

You need to take to experienced repairer to check out.

I once had a B&S compensated Eb tuba with similar problem which also drove me nuts - don't live with it but get sorted! Might cost you a bit, but it is useless as is.

[sousaphone68]

Neptunes suggestion to go see a repair tech maybe your final recourse but before you do there are two simple non tech things to check and try.
I experienced similar problems to yours with my Eb fresh out of the box, at first I thought it was a bad valve guide and Neptune supplied me with 4 new ones they improved the problem at first but it came back.
Upon further investigation ie trial and error I found two scenarios that caused the drag you described.
The factory springs look good and work but every so often on my set the top ring of the spring would dip below and entangle in the coil below and the piston drags, sometimes with a tell tale new noise. New springs fixed this.

The valve guides on my tuba are a plastic covered metal tang makes for quiet valves but I found that over time the guides creep out so once a month I strip of the guides and refit them being careful to keep pressure on the guide while tightening the stem and washer to prevent it from creeping while tightening. There is a location pin on the guide and a hole on the piston top to stop creep but the tolerances on mine are too great.

Your signature shows you have access to other euphoniums try borrowing a set of springs and refitting the guides you may be pleasantly suprised.

[pgym]

Funny this should show up just now.

I purchased an Andreas Eastman baritone (British bore) in July 2010 on the strength of Steve Shires' involvement in tweaking the design, training the factory workers, and QC of the finished horns. Your description of the intonation and fit and finish matched that of my Eastman to a T. Unfortunately, so did the sluggish valve problem, though mine were with 1 and 3 rather than 1 and 2, even after several rounds of washing, lapping, replacing the springs and valve guides, cleaning and deburring the guide slots, trying various oils, etc. When I finally got through to Eastman (which took several months), they arranged to have me ship the horn back to them at their expense for inspection, the result of which was they replaced it with a new horn.

Unfortunately, the sluggish valves showed up on new horn as well, at which point I wrote the whole thing off as a lesson learned. Stuck the horn back in its case, stuck it in the garage. That was Oct 2010.

Short story longer, last Monday, had one of those, "I wonder" moments while cleaning my euphonium, as in, "I wonder whether there's some residual lapping compound in the leadpipe and/or valve knuckles and slides that survived the factory power washing that's washing into the cylinders when I play?"

Retrieved the horn, mixed up a 60/40 solution of Simple Green and warm water, filled the horn and let it sit for a couple of hours, then pulled the valves and bottom caps, wiped down the pistons and snaked out the valve casings, leadpipe, and slides with straight Simple Green.

Oiled up the valves, reassembled everything, started playing and ... a week, Advent IV and Christmas Eve services, two Red Kettle sessions, and 8-10 hours of practice later, have yet to re-experience sluggish valves.

Maybe a (homebrewed) chem cleaning is in order?

[Dan Schultz]

Funny this should show up just now...... Short story longer, last Monday, had one of those, "I wonder" moments while cleaning my euphonium, as in, "I wonder whether there's some residual lapping compound in the leadpipe and/or valve knuckles and slides that survived the factory power washing that's washing into the cylinders when I play?"

Retrieved the horn, mixed up a 60/40 solution of Simple Green and warm water, filled the horn and let it sit for a couple of hours, then pulled the valves and bottom caps, wiped down the pistons and snaked out the valve casings, leadpipe, and slides with straight Simple Green.

Oiled up the valves, reassembled everything, started playing and ... a week, Advent IV and Christmas Eve services, two Red Kettle sessions, and 8-10 hours of practice later, have yet to re-experience sluggish valves.

Maybe a (homebrewed) chem cleaning is in order?

I had the same experience with some Eastman tubas that are owned by a local middle school. In my case... I think it was a combination of buffing grit and stainless steel valves. The valves would first become stained by 'black-ish' something and get sluggish. A few 'deep cleanings' and the problem went away.

[iiipopes]

Indeed. Thorough cleaning. For me, it's when I forget to clean the tuba after a gig where beer is consumed, and the residual malt crystalizes around a rotor.

[Rick Denney]

Has it occurred to you to consider taking it somewhere and getting it fixed?

That would involve paying a repair tech. That is obviously not be considered at all.

Rick "of course, not all of them are worth their money" Denney

[PaulTkachenko]

I ordered the bits to have a go at your DIY linkages, Rick.

If I can pull it off (I reckon I can), I will be most indebted to you ...

I think it's good to have an understanding of how our instrument works. I still spend a small fortune each year taking my tubas to expert repair people, but it's nice (and rewarding) be able to sort small problems out yourself ...

[MikeW]

This topic comes up frequently. An advanced search on "sticky valves" will turn up much useful stuff.

The problem only shows up when you are playing, so the most likely cause is crush syndrome - the instrument got a bit squashed or mildly clobbered in transit or storage, so the valve cluster and tubing has been bent very slightly towards the bell, which leaves torque in the tubing, which tends to distort the valve casings. Several people have mentioned that their valves seem free, but the extra forces on the instrument arising from holding and playing it are the last straw, and the valves start sticking. You can test for this by gently pulling the valve cluster etc. away from the bell while playing, to see if this eases the problem (or GENTLY press the valves etc. toward the bell and see if it gets worse).

If this is the problem, the damaged tubing needs to be eased away from the bell, back to its correct shape. This is not an operation for the inexperienced hand, you can very, very, easily make the problem worse, or wreck the instrument; Take it to a skilled repair tech.

An alternative cause is flimsy bracing. Again,consult a skilled repair tech.

PS. my own experience: after dropping the instrument and having it overhauled, there was a residual "ghost" that caused a sticky valve after playing for about half an hour. This turned out to be caused by torque in the mouthpipe; eventually the solder on the receiver brace gave way, which released the torque, and the problem stopped.

[euphomate]

bloke wrote:Has it occurred to you to consider taking it somewhere and getting it fixed?

I should have explained that I write from the southern hemisphere (Australia). It's summertime down here, a sunny 35C today in fact, but we need some rain soon. Our annual summer vacation time is centrered around the Xmas to third/fourth week of January. Factories and smaller trade places (inc brass techs) close down and head for the beach, leaving suckers like me with sticky valves. So I'm having a go to see if I can handle it in case it was to be an easy fix. Bloke, many thanks, but I had already done exactly what you described before I wrote. Didn't work. I'm attracted to the distorted tubing idea, as the horn has to be jammed real hard into the supplied case to zip it up. Feels as though the case is a tad too small, and distortion to the horn may have happened. I will also try swapping valve springs with the heavier duty Yamaha item from the 642. I appreciate the time taken by all to assist me with the problem. It's interesting that whatever I have tried hasn't made any difference at all, neither improved the situation or made it worse. This seems to point to one cause, not a combination of things. Keeping in mind that we down here spend our entire lives upside down, so it could be a gravity issue! LOL.

[Dan Schultz]

......I'm attracted to the distorted tubing idea, as the horn has to be jammed real hard into the supplied case to zip it up. Feels as though the case is too small, and distortion to the horn may have happened. ....

It's a very bad thing to grab a horn by the valve cluster to push or pull it into/out of a tight-fitting case. I haven't seen it happen on a lot of euphoniums but this practice will sure 'kill' an F horn.

Properly fit.... pistons only have about .0005" of clearance. It doesn't take much valve cluster distortion to eat up that sort of tolerance.

[euphomate]

the guides are too tight.

The guides are just solid plastic, and if I move the valves up and down while twiddling the guides back and forth in their slot there seems to be plenty of clearance, as I can hear and feel the guides tapping away against both sides of the slots (if that makes any sense). But I will take all advice offered and start the process again. If no success, I'll wait for my tech to return from his summer vacation. But heck, would love to fix it myself.....................

[termite]

Hi John

He's probably on holidays right now but the best person I've found in Melbourne for valves is Daniel Bogeman on 9818 8520 in Hawthorn.

He fixed the long standing first valve problem on my 1291 once and for all.

There's another long established business known for their excellent scratch and dent work that I would NOT takes valves to.

Regards

Gerard

[euphomate]

He's probably on holidays right now but the best person I've found in Melbourne for valves is Daniel Bogeman on 9818 8520 in Hawthorn.

Thanks Gerard. I think I've fixed it, a mixture of the kind advice I got through TN. I heard today that Markham (brass tech) down at Brass & Woodwind has left. Pity, he was good with a magnetic dent kit.That doesn't leave many of his type left with Billy Hyde gone. Daniel might come in handy. Happy New Year.

[termite]

G'day John;
Happy etc. etc.

Daniel is ex. Billy Hyde - he and the woodwind guy went out on their own.
Markham is pretty good too although the shop he was at knew how to charge. (No-one's reading this, right??)

Regards

Gerard