Piston valve problem.

[Tubaplayar]

Hello there, I am new to this forum, and I was wondering because I have a EEb Miraphone, which has piston valves, which I got second hand and for some odd reason, even though it has been happening less and less recently (because I have had it for a few months now!) it still happens once or twice during my practises, the valves have been going up slowly at random times, I do not get why it does it, but it does it, please could someone help me try to get to the bottom of this?I have cleaned the inside of the casing and I have cleaned the valves and I have oiled them.

And I am sorry if this topic is in an inappropriate place to put it, but I do not know where else to put it as I am new to the forum!

[ddoppler]

I should start off by saying that I am certainly not an expert in this area and there are several members of this forum that repair instruments for a living that routinely give GREAT advice and might give you different advice from what I'm about to suggest (which is one of the reasons I love this forum).

Having said that... I think one thing you could try is to switch to a different valve oil. I was having a similar problem with my euphonium and my baritone, both Yorks with stainless steel valves. I was using Al Cass valve oil and I switched to using La Tromba. I believe the difference here is that La Tromba is synthetic and Al Cass is not. Since the switch about 3 months ago, I have not experienced the same problems. There are other oils that people swear by as well that could also work... Yamaha synthetic, Hetmans, etc.

If you try this, make sure to clean out the casings again (don't mix the different kinds of oil). Good luck and welcome to the forum!! I hope you get as much out of it as I do!

[Tubaplayar]

Thank you very much sir! I certainly see a lot of things that would come in handy for tuba playing and maintenance!

[prototypedenNIS]

If the horn is clean and the problem is intermittent while playing, the first thing I'd check would be technique.
Are your fingers applying force directly downward on the top of the finger button?
Are you using your right hand for the bulk of horn support and pulling on the tops of the stems or pulling (by friction) on the tops of the finger buttons?

A good home way of checking for mechanical problems is to place the horn upside down on top of a table (on bell), remove the bottom valve caps and springs, push the valves up and release. Given the weight of the valves alone, it should drop back down immediately and without binding.

[davewerden]

How are the braces on this horn? If you have a missing or loose brace, and if you squeeze the tubing too tightly, it is possible to distort the framework just enough to hang a valve.

I still remember the very first production model of the compensating Miraphone euphonium. It was not braced well enough on the first valve slide and you could push it just a bit and stop the valve in its tracks. But I think that was a rare thing for a Miraphone design, which is why I wondered if your bracing is not factory-fresh.

[prototypedenNIS]

nice point Dave, that is a very common problem in Amati tubas and euphs.

[Tubaplayar]

Thank you for the suggestions, and what are the braces? And thank you Prototype, I generally try to play without putting any friction on the valves and make sure that I push straight down onto the valve, but when I do practise next I shall pay extra attention and get back to you on that one! Thank you so much, I will try these things out. I am highly appreciative of this!

[davewerden]

Originally posted by: Tubaplayar ...and what are the braces?

Braces are the skinny rods that go between the main tubing and "brace" it so the horn is structurally strong.

[Tubaplayar]

Thanks for the input people, my name is Ben, and I have tried to make sure that my fingering didn't cause friction, but every so often it does still do it, but I think it is mostly my technique and I have changed it and it happens mostly with second valve, and sometimes the 3rd valve is hard to press down (even after just oiling it). The person who I bought it from suggested that I brought it back to have the valves grinded? I don't really know what that does, but what do you think?

[davewerden]

I would not hurry to have the valve ground. In most cases it is not necessary.

But it might be wise to take it to a good repair shop and ask them what they see. It's possible that the horn needs a good cleaning inside, and any good shop can do that. If the interior of the horn is not clean, small bits of crud can find their way to the valves and cause trouble. Even if the interior of the valve cylinder looks good, there could still be dirt/slime/etc. hiding in the tubing, just waiting to work into the valves.