Page 1 of 2
Valve Realignment
Posted: Thu Jan 11, 2007 6:01 pm
by Thomas Maurice Booth
I have a four piston/1 rotor 4/4 CC tuba that I believe needs a slight valve alignment. What should I expect that to cost? How difficult is the fix, how long will I need to have the horn in the shop? Any recommendations on repairmen from Central Indiana or Southwestern Ohio? All input appreciated.
TMB
Posted: Thu Jan 11, 2007 8:42 pm
by Dan Schultz
If nothing has been broken or bent, an alignment check/adjustment should be fairly painless.
Posted: Fri Jan 12, 2007 12:46 pm
by Chen
Has anyone got valve alignment done by Bob Reeves in California?
Posted: Fri Jan 12, 2007 12:47 pm
by ASTuba
Chen wrote:Has anyone got valve alignment done by Bob Reeves in California?
Yeah, I know people who have had them done by Bob and other people. It's made a difference, although some of them will argue if it was worth the cost of having it done.
Posted: Fri Jan 12, 2007 1:55 pm
by ASTuba
the elephant wrote:This is not some deep voo-doo like realigning valves in a car engine.
It is simply using a light and a special little mirror to see whether you need new felts and corks under the finger buttons and valve caps. That is it. No mojo. It is easy, but a bit time consuming. The tech needs to make certain that the piston port and the casing port are exactly in line when both up and down. Then they shim both ends with felts and corks of the correct thickness. Just be aware that some felts bloat with water and oil even if you are very careful and try not to get oil on them (keeping felts dry is pretty much impossible*), so what looks great today will be "off" after a few hours of playing. A good tech will know which felts bloat and by how much and will oil them a bit so that they are "pre-bloated" prior to making the adjustment.
Wade,
It's not quite as simple as that. Bob, Wayne Tanabe, and others, often will make plastic inserts for the top of the valves, thus allowing as thin of a felt to be used. The thought behind this is to allow the alignment to last longer, because they're not using a cork washer.
I've never had a Reeves alignment done, but I'd be interested to try my tuba out after one, and see if I notice any difference.
Posted: Fri Jan 12, 2007 2:11 pm
by ASTuba
the elephant wrote:I know that. I have repaired horns quite well for about 13 years now. I was trying to simplify what is going one. It is not some magical process like some seem to believe. That was my point. I have done many valve realigments, and that is exactly what is done by most people. I don NOT want such a thin felt in my horn. I hate that dead feeling. I have made shims too but stopped after I decided that I did not like the resulting feel.
Wade,
Just explaining a little more detail. I have no idea about anyone's background on here, so I thought I would explain a bit more.
I like thin felts as much as possible, as I hate how felt compresses over time.
Posted: Fri Jan 12, 2007 2:20 pm
by Dan Schultz
ASTuba wrote: I like thin felts as much as possible, as I hate how felt compresses over time.
Me too. No more than 20% or so felt. The rest cork.
Posted: Fri Jan 12, 2007 2:39 pm
by Thomas Maurice Booth
To further explain my problem, my 2nd and (sometimes 4th) get stuck up halfway up after the piston is released. There doesn't appear to be any marks on the side of the piston as if the valve was scrapping against the casing. I switch the angles I push the piston in and that doesn't seem to always work either. Hope this will help me figure out if a valve alignment is necessarr or what else needs to be done. Thanks again.
TMB
Posted: Fri Jan 12, 2007 2:43 pm
by ASTuba
Sounds like you need a trip to the shop, there may be a need to repair a slightly out of round casing, valve, or something else.
Posted: Fri Jan 12, 2007 2:46 pm
by ASTuba
Wade,
I've stopped using cork washers anymore. I'm using synthetic washers I get from either JL Smith or Ed Kraus.
Posted: Fri Jan 12, 2007 2:53 pm
by ASTuba
They cost a bit more, but they don't squish at all, and I've never had to replace a set of them due to a change in their dimensions, only because they got ripped by some one's attempt to do something else...
Posted: Fri Jan 12, 2007 2:58 pm
by Alex C
Thomas Maurice Booth wrote:To further explain my problem, my 2nd and (sometimes 4th) get stuck up halfway up after the piston is released. There doesn't appear to be any marks on the side of the piston as if the valve was scrapping against the casing. I switch the angles I push the piston in and that doesn't seem to always work either. Hope this will help me figure out if a valve alignment is necessarr or what else needs to be done. Thanks again.
TMB
That isn't an alignment problem, you have other issues.
Wade is right, aligning valves is not a huge issue most of the time. Not meaning to take away needed work from a repairman but...
I've bought a dentist's mirror (on an angle) and used a small gooseneck light to line up the valves on my new tuba. Not only were they out of alignment but it became clear to me that it was impossible to line the valves up with all of the ports.
At the Midewest Clinic, a friend mentioned this to the manufacturer who confirmed what I found. They build the valves so that the ports are aligned with all of the valves UP. When depressed, it's a matter of trade-off's.
Which leads me to Dan Oberloh's wonderful web-pages where he rebuilds the Holton valves. It's the only solution that makes sense even though it's probably overkill.
http://www.oberloh.com/gallery/tubavalvereferbish.htm
Posted: Fri Jan 12, 2007 7:04 pm
by Dan Schultz
Thomas Maurice Booth wrote:To further explain my problem, my 2nd and (sometimes 4th) get stuck up halfway up after the piston is released. There doesn't appear to be any marks on the side of the piston as if the valve was scrapping against the casing. I switch the angles I push the piston in and that doesn't seem to always work either. Hope this will help me figure out if a valve alignment is necessarr or what else needs to be done. Thanks again.
TMB
Could be lots of things but it's not likely that a valve alignment would help. Take your horn to a repairman and let him have a look.
Posted: Fri Jan 12, 2007 11:26 pm
by Thomas Maurice Booth
The valve does not stick all the time. I notice it most after several hours of practice or when I am first picking up the horn. I am preparing for a good number of auditions and do not want my horn to act up at an inopportune time. Thanks for everyone's input it has been very helpful.
TMB