The Art of Woodwind Repair www.woodwindshop.com

20Mar/121

The Art of Fitting a Sax Neck

Back in the '70s I had the opportunity to work with the guru of neck fitting, Bob Gilchrist. Bob later went on to work at the mecca of repairs for the San Francisco Area, the House of Woodwinds in Oakland. Bob and owner/repairman George worked together to bring the art of neck fitting to a new level. Bob later moved to LA, and then a few years later I was able to get him to move back to the Bay Area to work in my shop, Marin Woodwinds. It was truly a privilege to work with one of the Masters.

Bob really preferred to work on flutes, and he is probably the foremost authority on fitting flute head joints. The principals of sax neck fitting and flute head joint fitting are very similar. At one point I also specialized in flute heads, but over the years I gravitated towards saxes, which are my favorite horns to work on. I've hand fit the neck on brand new out of the case saxes, overhauls, and horns only needing minor adjustments. They all benefitted from an adjustment of the neck fit. I've repaired for over 20 years and worked on several saxes a week, so I estimate I worked on no less than 2000 saxes, many of them top end horns. You learn a lot over 20 years! Some is pretty esoteric stuff, some is quite tricky (fitting the double neck on an old Conn, for example), some is pretty cut and dried (100% of the Selmers I've work on have exactly the same problem!).

First, why does fitting the neck affect the tone? I honestly don't know the physics of this, but I have a pretty good guess. Get the idea that the wave for each note is a different length. That means the peak for each wave (node) will strike the inside of the bore at a different point. Imagine that the high B and Bb peak just before the tenon of the neck. The A and G# peak just inside the neck, the G just below. The notes that peak inside the neck are more affected by the fit than those that peak just above or below. The notes that are MOST effect by the neck fit are D,F# A.

Ok, let's test this out. Play a middle F and F#. Are they equal? If the F# is weak, you need to have the neck fit! Play second octave A, G#, G. Is the tone quality and color exactly the same on each? If not, you need to have the neck fit!

I like to use the F-F# as my starting point. As you work on the neck the F will barely change, but the F# will get better and better until the F and F# sound almost exactly the same. The same is true playing A, G#, G. And, as an added bonus, when the A and F# are clean and clear the middle D will also improve.

I know there are those that will say this is all BS. But, as they say, the proof of the.... All you have to do is pick up any horn at random and see if the A, G#, and G are equal, does the F and F# have the same tone quality, and if they are not all balanced, does the middle D sound weak? If the horn is a Selmer and the F# really sounds bad, look in the receiver and see if there's a little bright 'bar' of contact next to the screw slot. I see that on 100% of the Selmers I work on (unless it is new out of the box).

What, exactly do I do to fit a neck? I look at it. I know that sounds too stupidly simple, but that is what I do. I look. And what do I see? I can see high and low spots inside the receiver and on the neck. And then I raise up the low spots and rub or file down the high spots.

Obviously it is much easier to grind away the high spots. Just get a big file and have at it. Ok…that's not really how you do it! Just grinding away the high points will very likely make the fit too loose. When I fit a neck I do remove some metal, but I use #6 files and #600 grade sand paper. You may have never seen a #6 file...I had to order them from a jewelry supply house. They are so fine you can hardly feel the file surface, so they are perfect for removing as little as 1/1000th of an inch (or less). As a point of comparison, 1/1000th is about the thickness of a sheet of tissue paper.

I start by just looking at the neck the way it is. You can see easily patterns of light and dark. The light is where there is contact (high point). The dark is where there is no contact (low point).

I start with the receiver. Unfortunately you can only work down the high points. As much as possible I rub them down using a dent ball or burnisher (a burnisher is a very hard highly polished tapered piece of steel). Remember that really bright little bar inside the Selmer receiver? You have to really put some pressure on it to work that down, and for that you definitely need to use a dent ball.

If it's necessary to polish out a few high points I use either #600 sand paper, or a fine grit jewelers polishing wheels for a dremel type motor. The one that's easiest to work with is shaped like a bullet. Using that it's possible to remove very small and specific points within the receiver.

The neck tenon is a little easier to work with because the outside surface is more accessible. If the highs and lows are very obvious I can start right in by raising the low points or removing the high points. If it's not very clear, you can either run a #6 file around the surface and the high points will immediately become very bright and shiny. The other method is to take a used piece of 600 grit sandpaper (or a new piece of 1500 grit if you can find it). This will make the entire surface somewhat "matte". Put the tenon into the sax and work it back and forth a couple of times. The high points will become shiny against the matte background. You might need to try a couple of different types of light source to get the most contrast.

It's very very common for there to be a band at the very tip of the tenon and another extending 1/8" just below the shoulder (the connection point between the tenon and the neck). If you did nothing more than to remove those two bands using a #6 file, you would be amazed at the improvement! One point worth mentioning here, especially when working on brand new horns. Very often there will be a little lacquer "over spray" on the tenon, and you must must must remove that first thing before doing anything else! Rarely will you see a little lacquer overspray inside the receiver, which must be removed before doing anything else, but that is very rare.

It is more common for the neck to be slightly loose than tight, so the best solution is not to lower the high points but to raise the low points. There is a tool that looks like two wheels slightly offset with a big crank handle that is supposed to expand out a neck. If I ever meet the guy that invented that thing I would like to shove it...sorry. I think he also invented the Guillotine (or maybe it was the Yugo). If you ever see someone using one of those things run as fast as you can and take your horn with you.

The proper tool to use is the neck expansion tool sold by Ferree's. This is a tube about 8" long with sections that expand at the tip as you tighten the knob on the back end. You can expand the tool and then shove the neck on to expand the tenon, but I don't recommend doing that. It almost always over-expands the very very tip. It is better to put the neck on the tool, and then use a pipe wrench to expand the tool and work the neck back and forth over the point of contact. Release the tension before you pull the neck off so that you do not accidentally over-expand the very tip. When I say "point of contact", only about ¼" of the tool surface actually makes contact with the inside of the tenon, so you have to know where that is and position it directly under where you want to expand.

Ok, here is the formula to Kentucky Fried Chicken, the secret ingredient to Original Coke, the Secret Teachings of All Ages as handed down from generation to generation of Rosicrucians, Shriners and Templar Knights. If you put the neck on the expander, put some tension on the inside, and then RUB ONLY THE LOW POINTS WITH A BURNISHER the low points will raise up. I don't totally understand the mechanics of why this works, but my guess is that it has to do with "metal memory". If you bend (expand) a piece of metal it will want to return to its original shape. If you apply pressure downward against the pressure being supplied by the expander, the metal seems to 'bounce' outward and retain that shape. When you release the pressure of the tenon tool, the neck will return to 99% of the original shape, except where you rubbed it with the burnishing tool. Those points will rise up in relation to the surrounding metal.

A couple of notes: First, different saxes react differently to the amount of pressure you apply, so start with a little and work up. It's very difficult to put enough pressure to move a really hardened piece of brass (like a Selmer), so you have to use a pretty fair amount of pressure, and it's not easy to do that by hand. So I use a pipe wrench.

Next, if the entire neck is loose and the metal moves easily, put the tenor on the expander, put some pressure, but make it so you can still move the neck back and forth. Move the neck back and forth a couple of times. Loosen the expander and move it 1/4" or so up or down, and repeat the process. Remember that you only have about 1/4" of working area on the expander, so you may need to repeat this several times. Try to get the exact same amount of pressure each time so you get even expansion. Test often! Make sure you're not over-expanding.

Now that you've got it pretty close, go back to the steps above for rising up one low point here or there: put the working area of the expander under the low spot, put pressure on it from inside, rub with a burnishing tool.

Note regarding the location of the "working area" of the expander: it's about 1/8" back from the tip. You won't see it when the tool is brand new, but after you've done a few necks you'll start to see a wear pattern on the expander that will tell you exactly where that sweet spot is located!

As you work it will become difficult to see where the highs and lows are located, so go back to cleaning it up using "used" 600 grit or new 1500 grit sandpaper. Put the neck into the receiver and turn it back and forth. Once again you'll easily see the highs and lows, both in the receiver and on the tenon.

One last note regarding the receiver: sometimes there's a little "over spray" of solder down at the bottom of the receiver where it was attached to the body. You'll have to use a pointed solder scraper to go in there and take that out.

Ok, the following comes with the message: warning, don't do this at home! If you have some super fine lapping compound handy, you can sometimes "lap in" the neck a little. I only do that when there are highs and lows all over the place on both the neck and the receiver. You have to be super super careful that you don't get the neck stuck into the receiver (been there, done that!). If you do, you'll have to work some oil down into the receive and gently try to rock the neck back and forth. When you're done, be sure to really clean all surfaces, especially the "crack" where the neck screw comes together.

DISCLAIMERS! This information is intended for the use of a qualified repairman with the proper tools. For the "do it yourselfer", you can with some success remove a few high points off the tenor and maybe clean up the tenon a little. Second, I know there will be the temptation to try this as the magic bullet that will solve hunger in third world countries and achieve world peace. I stress that neck fitting falls under the category of "fine tuning". If a horn has any (notice that's BOLD ITALIC and UNDERLINED) leaks you are wasting your time messing around with the neck. It's like trying to adjust your carburetor when you have bad spark plugs. Ok, bad example…no one has a carburetor these days. Ok, it's like trying to lose weight by cutting out the olives on those extra large pizzas. In other words, you have to look at the big picture. Leaks can cause the F# to sound fuzzy. You can fit the neck for days and it will not sound any better until you fix that leak. But, if the horn has been checked out and is certified to be 100% leak free, now you can look to see if the neck needs to be fit.

Many years ago (when I was a "youth") my high school buddy Jeff Ervin dropped by the store I was working at. Bob Gilchrist had just showed me the trick of fitting a sax neck a few days before, and I had now fit exactly two necks (so I was an "expert"). I talked Jeff into letting me fit the neck on his Selmer Tenor (why think small and practice on a couple of student horns???). A couple of days later Jeff, good friend that he was, walked into the House of Woodwinds and handed Bob his sax. He pointed at the neck, which was totally stuck into the receiver and could not be pulled out, and said "Mike said that you taught him how to do that". Bob was not amused. So my final words of caution are: start with a few cheap horns, and don't over expand the neck!