Valve Alignment at Home

Discussion in 'The Rehearsal Room' started by DS2014, Apr 21, 2015.

  1. DS2014

    DS2014 Active Member

    Warning: Geek alert!
    I know I'm a geek, so, don't bother reading this thread if you're not also geeky about the engineering of brass instruments.

    Apparently, it is quite common for the valves on brass instruments (even new ones!) to need alignment. The difference this makes to the play-ability, intonation, and slotting of the instrument is supposed to be quite significant. I've been doing a bit of research on this, and have discovered that it is possible to do a pretty good job at home with only some basic tools, and I wonder if any of you have ever taken this on? If so, what tools did you use? I'll post a piece I found on The Trumpet Herald about how to do a DIY valve alignment in the next posting.
    Last edited: Apr 21, 2015
  2. DS2014

    DS2014 Active Member

    The following was posted by a fella from London, and the original thread can be found over on The Trumpet Herald

    Some don't agree with doing this and that's fine. Sure some will feel they need .001 to be happy. If you start with an instrument that is off by 1/32" you will love getting it to better than .01 for sure! Someone is sure to come out with a machine that will do .0001 someday, and there will be folks out there willing to pay for that kind of accuracy too, and suddenly .001 will be frowned on.

    A valve alignment done correctly at home can significantly improve your horn's playability. One set of ports (the "thru" ports) must be aligned with the main "thru" tube (in the up position), and the other set (the "valve" ports) must be aligned with the valve slides (in the depressed position). You need to have a quality measuring tool (something at least as good as a narrow 1/64" increment metal rule and preferably closer to a precision instrument. Yet even with the simplest tools and careful work, one can get within a hundredth of an inch vertically. And while it isn't the thousandth of an inch that the best pros can do, it's virtually free, takes about an hour (the first time), is far better than doing nothing, and frankly, I don't think I'm enough of a player to notice a few 1/1000s difference. My goal is to prevent any significant inconsistencies, reduce valve cluster induced intonation problems, and achieve the best performance/price ratio that I can.

    Then one needs to be very patient taking precise measurements. Remove all worn or additional shims before you begin.

    First let's define these terms.....
    For the purposes of this explanation, I'm choosing to call the tube going from mouthpiece to bell (without depressing any valves) the "thru" tube. The ports on each valve that line up with the thru tube will be called the "thru" ports. Likewise, the ports on the valve that line up with the valve slides will be called the "valve" ports. Finger buttons are what you put your fingers on, and valve caps are what you tighten to hold each valve in its casing.

    Then we define the measurements for each valve.....
    A= distance from bottom of the valve casing to the bottom of the valve itself in up position.
    B= distance from bottom of the valve itself to top-centre of lower thru-port on the valve itself. Measure this with the valve removed (obviously).
    C= distance from bottom of the valve casing to top-centre of the thru-tube inside casing, again with the valve removed.
    D= distance from bottom of the valve casing to bottom of the valve itself in depressed position.
    E= distance from bottom of the valve itself to top-centre of the lower valve-port on the valve itself. Measure this with the valve removed (obviously).
    F= distance from bottom of the valve casing to top-centre of the lower valve-slide inside casing, again with the valve removed.


    (1) Compare thru-ports with up-position. Measurements should equal A+B=C. If A+B>C, add shims under the valve cap. If A+B<C, remove shims from under valve cap.

    (2) Compare valve ports with down-position. Measurements should equal D+E=F. If D+E>F, remove shims from under finger button. If D+E<F, add shims under finger button. Writing down your measurements with no shims used at all will give you a baseline that you can use again and again without having to go through this process.

    A word about shims. Yes, felts do compress, but yes, they are quiet. I prefer using rubber washers for big adjustments and mylar notebook reinforcements for small adjustments. They last a long time and do not appreciably compress. If the valve noise is bothersome, you can use a very thin felt on top of everything else (thickness factored in, of course) and replace only the felts as they age or compress with new ones to regain alignment accuracy.

    I do my own "AVA's" (Amateur Valve Alignments) and I've had very good luck with them. My non-compressible spacer materials consist mostly of a stack of mylar notebook reinforcements. I can only adjust the vertical alignment, but I can easily get beyond .01 of an inch with a metal rule calibrated to 1/64", and even better (at least more reliable) with a precision measuring instrument.
  3. Bbmad

    Bbmad Active Member

    As it happens, yes.
    2inch spanner
    A garden trowel
    5kg of plaster of paris
    A sturdy hammer
  4. Feel My Rath

    Feel My Rath Member

    Get a slide, it's much more simple. I'm sure Mr. Bbmad would agree.
  5. DS2014

    DS2014 Active Member

    Ah yes, those lottery-era Besson instruments did need a lot of work :)
  6. Tom-King

    Tom-King Well-Known Member

    I'm aware that valve-alignment makes, potentially, a big difference (especially if way off) and noticed significant improvements in almost every instrument I've done it on (2 sops, 2 Bb's, a Flugel - on a particular Courtois flugel no improvement, it was still awful).

    What you've posted is a thorough and well thought-out method and it'll work... however, a few criticisms:
    1) It's only as good as your measurements.
    2) Any mistakes in measurement or recording will result in errors in your alignment at the end of it.
    3) It's very slow. Whether you're writing this out on paper and calculating yourself or rolling the numbers through excel, it's going to take time.

    I do mine myself, but use a different method.

    First things first - the basics:
    Valve alignment affects open (up positions) just as much as it does when the valves are pressed.
    The down positions are effected by the thickness of the felt on the topcap (or in the finger button), the up positions by the felts on the valve stem (the one you don't see when the valve cap is screwed on, which rests against the underside of the cap).

    You can see the alignment of the down position of the second valve easily - pull the slide out, press the valve down and have a look. The 1st and 3rd aren't quite as easy to see.

    To see the "up" position, how the valves align when not depressed, you'll need to look through the port of the valve next to it... which means you need something that enables this, fortunately a suitable tool is available on Ebay for <£10 (search for "borescope" and you'll find USB cameras that will do the job -- note: you need one that comes with the 90 degree mirror attachment, which most seem to).
    ***Warning: The head of this is metal (probably aluminium), so be careful not to scratch the valve casings***

    The images you'll see are like this (not the best picture):

    As you can see, this valve is sitting too high, the misalignment is an obstruction.... as this is the "up" position, this means the felt is too thin.

    There are two solutions:
    1) Get new felts and fit one on this valve. If they're old anyway, I'll start there (as I have some anyway).
    2) Put something thin underneath the felt to boost it up. Curiously, the valve stem is the exact same size as a standard holepunch... so hole reinforcers work nicely.

    Now put it back together and look again - is it right?

    Removing valve 2 you can align 1&3, either 1 or 3 (or both if you like) can be used to see #2.

    To do the down positions:
    Push the valve down, and use the borescope to see the alignment (without the mirror on #3, depending on your eyesight maybe not at all on #2... on some instruments #1 is difficult to see).
    If the valve is sitting too high then the felt is too thick - either use a thinner felt or thin the felt down (rubbing on emery paper or very fine sandpaper will do this... coarse sandpaper will make a mess of it). If the valve is sitting too low then the felt is too thin, either replace with a new (or thicker) felt, or stick bits of sellotape to the cap so that the felt sits higher.

    This whole process will take about half an hour the first time, and can be done in less as you get used to it.
  7. Ianroberts

    Ianroberts Well-Known Member

    Mole grips, big hammer and WD40 are all that is required
  8. DS2014

    DS2014 Active Member

    Tom, thanks a million for this. I've ordered myself a borescope off eBay for less than a tenner.
  9. Tom-King

    Tom-King Well-Known Member

    Anytime :)

    It's a really easy and satisfying way to get a noticeable improvement* - a slightly more open, even blow and slightly improved intonation.
    *Well, as long as the alignment is off to begin with

    The only experience I have with checking a new instrument is with my Eclipse Sop.
    Knowing how worthwhile it was with the Xeno I decided to check it (regardless of the fact it comfortably outplayed the Xeno anyway), all positions were pretty much spot on except for 2nd valve down - rubbing the top felt on emery paper reduced it enough to get the alignment perfect. Nowhere near the huge improvement that I noticed on the Xeno sop (which needed 5/6 alignments modifying, and is a much tighter blow & smaller bore to start with) but I'm still glad I checked - if nothing else, I know there's nothing compromised there.
  10. 2nd tenor

    2nd tenor Well-Known Member

    Thank you for raising this topic, and thanks too to Tom King for his helpful comments. In my experience making sure that what you play is correctly set up and in in good condition does make a difference to how well you can play and allows you to make the best of what you have got.
  11. 2nd tenor

    2nd tenor Well-Known Member

    I believe that Mr Bbmad is a BB Bass player (BBmad?) so he probably wouldn't know much about trombones - he has expressed interst in becoming a trombone player but it is a big step to (sucessfully) make.

    For those that haven't played a trombone I would add that whilst slides look simple they aren't and slides are a real pain to get sorted and keep in good condition. I had a slide rebuilt a while back and can now concentrate on playing rather than managing a slide that has a mind of its own.
    Last edited: Apr 22, 2015
  12. Bbmad

    Bbmad Active Member

    2T, I think that you might have the wrong thread, the "I Believe" thread is in the Off Topic and Random threads section.
  13. 2nd tenor

    2nd tenor Well-Known Member

    A very clever answer, skillful. What's such a puzzle is why someone with brains (you're far from thick) would write responses (like #3 above) that have so little use. Why be difficult and damage the forum with unhelpful and seemingly silly posts when you are capable of being an asset to the forum and someone who might have something useful and constructive to say?
  14. DS2014

    DS2014 Active Member

    OK, fellas, here's an update on my DIY Valve Alignment.

    So, I ordered two tools off eBay: a depth gauge (a thin ruler with a sliding measurement reader) for £2.99 and a borescope for £6.99. I got both in order to cross check my measurements.

    First, I did the detailed manual measurements as described above just to see how accurate they were. What they showed was that the upstrokes on all three valves of my mint-condition, 2011 Yamaha Xeno cornet appeared to be out by either 1/64" or 1/32". The downstrokes on valves 1 and 2 were out by a similar distance, but valve 3 was fine on the downstroke.

    Second, I used the borescope to have a look, and, sure enough, what I could see on all three valves matched with what my manual measurements said.

    So, I dealt with the upstrokes first, because they're the easiest. I added some of those hole-reinforcement things that one uses to protect the holes on papers to be put into a ring-binder. I placed two or three of these under the felt that sits on the valve stem under the valve cap. By trial and error, and using the borescope to check the alignment inside the valve, I got it lined up perfect...valve by valve (using the empty cylinder #2 to look in at valve #1 and valve #3; and then using the empty cylinder #3 to look in at valve #2).

    Next, I dealt with the downstrokes. I used a small screwdriver to loosen the felt that sits on top of the valve cap (the one that stops the finger button making a noise on the downstroke)...they need to be gently loosened since they are lightly glued on and you don't want to rip it. Once removed, I cut a thin piece of cardboard into the exact same shape as the felt and inserted it beneath the felt and reassembled the valve. Then I checked alignment with the borescope and, as luck would have it, the cardboard was exactly the right size (if it hadn't been, I would have just looked around for something else).

    So, tomorrow, I'll get a chance to give the cornet a good workout and see if I can detect any difference and I'll post something on here.

    Even if there is no discernible difference, I still think it was a good process to go through. I learned a lot from it, and, in the end, the cornet is better aligned than it was. After all, you wouldn't buy a £1000 suit and not iron it, now, would you?
    Last edited: Apr 26, 2015
  15. Tom-King

    Tom-King Well-Known Member

    Good stuff.

    Sounds like your measurements were pretty good! The borescope makes it nice and easy to see when it's wrong and whether you've got it right or not.

    Hopefully you'll notice a worthwhile difference!
  16. Cornet Nev.

    Cornet Nev. Member

    OK, sticking my neck out a bit, as a part time repairer and not pro, I do sometimes wonder about what else might be wrong on an instrument if the manufacturers can't be bothered to make sure valve alignment isn't correct before it leaves the factory.
    I haven't commented on this thread till now as I wanted to see what others thought first. However it is something I have also found and rectified on instruments that weren't even given for repair for that reason, usually broken joints or dents perhaps and poor playing and intonation not even mentioned.
    Indeed those hole strengtheners for paper documents are ideal and used them myself.
    As for why it makes a difference, a badly aligned valve presents a wall to the air flow, that creates swirling eddies in the air flow which can really mess up overall performance of the instrument.
  17. Tom-King

    Tom-King Well-Known Member

    Not sure it's anything to worry about - I'd put it down to simple tolerances and assumption.
    Several bits and pieces being off just enough to add up to minor misalignment (eg: felt thickness, rod length, topcap thickness, valve port positions, casing port positions), even with tight tolerances, a few of these being out by acceptable amounts may well add up to a few fractions off perfect alignment.
    As long as individual parts are within tolerance, it's probably expected that the alignment will be tolerable, which it is (the instruments we're talking about here are playable) taking the time to get it closer it doesn't make unplayable instruments playable, but it can give you a noticeable improvement.

    Sure it's simple enough to check it (as we're describing here) but that's extra labour time... which would be reflected as extra cost - not sure how many people would want to pay for that, especially considering these alignments aren't even permanent!

    And therein lies the rub - alignment changes over time.
    The felts wear and that changes the alignment, it may be necessary to check at regular intervals and re-adjust.

    In the case of the Yamaha's being discussed here, if you look at the buttons (and at the felts on the topcaps), what you'll notice is that the edge that contacts the felt is thin, and that it leaves a clear imprint (a circular slice/cut if you will).
    So lets assume (dubious as it is) that a given cornet leaves the factory perfectly aligned... with use, the button will cut into the felt when depressed, causing the downstroke to be misaligned a little.
    Last edited: Apr 30, 2015

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