Fixing woodwind cracks with carbon fiber banding

A relatively new way to fix cracks in woodwind bodies is carbon fiber banding.

carbon fiber

carbon fiber

The first step is to cut a channel for the fiber to lay in. I did this on the lathe.

 

channel

channel

Then we lay some epoxy in the cut and wrap the carbon fibers around, making sure we get them covered in lots of epoxy.

 

crack3

I cut off the excess fiber and let the joint sit overnight. Once it is nice and hard, I sand the excess glue and fiber down until it is even with the body. A little bit of light sanding with micro-mesh afterwards and the band is hardly noticeable. Unfortunately, I don’t have a picture of the finished product as a metal ring went over the banding so you wouldn’t be able to see it anyway.

Trip to the Burkart Flute factory

 

Image

Sorry for the bad quality, this was taken during my pre-iPhone days

 

 

I went to the Burkart Flute factory just outside of Boston a few years for a repair clinic and while the clinic itself wasn’t all that interesting, the tour of the factory defiantly was worth the trip. Burkart makes top of the line flutes with their lowest priced model starting at around $10K and their highest listed flute being close to $50K. They actually have and even more pricey model but it’s by request only. I don’t know anyone who’d spend $50,000 on a flute, but I asked one of the craftspeople how many flutes they actually sell and she told me they were backlogged a year at that point if I remember correctly.

Much of the price point is accounted for by the cost of raw materials; silver, gold, and platinum don’t exactly compare with the price of brass. Burkart had a safe full of gold and they let me hold a big piece of round silver stock that must have been about 3 pounds. Probably the most expensive thing I’ve ever had my hands on! In addition to the materials, the machines they use are very expensive as well. They had a few CNC lathes that run around half a million each as well as computerized milling machine which was very cool.

They also showed us some instrument bodies and parts they were manufacturing for other instrument makers. The owner wouldn’t tell us who they were doing work for but they had a bunch of french horn rotor assemblies as well as Oboe bodies they were making with the computerized milling machine I mentioned. That thing was amazing; once it had been programed (which was a lengthy process), it could churn out a flawless Oboe body in something like 5 minutes. The measurements were so exact that when we tested putting a rod screw through the posts, the alignment was absolutely perfect; you could drop the rod right through and it wouldn’t catch or wobble one bit.

Burkart also makes piccolos from grenadilla wood which they let season for two years before using. They told us that a big reason so many clarinets crack these days compared to times past is because the manufacturers are not waiting nearly enough time and letting the wood season properly. Apparently this is due to the shrinking numbers of the African Blackwood trees available as an increase in demand. It may be that sometime in the near future, there will be no more grenadilla instruments because of over-harvesting.

Finally, we got to see how their flutes are actually made. As you can see in the above picture, the manufacturing floor isn’t very fancy; just a big room with lots of benches and soldering torches. All the flutes made there have soldered on tone holes if memory serves and most of the parts are made from precious metals. I think it would be nerve-wracking to be soldering onto solid silver and gold body tubes all day; too much heat and you melt the thing. They told me it happened sometimes but it really wasn’t a big deal because they can just melt it down and remake it, a luxury afforded in manufacture that we defiantly do not have in the repair shop. All of the parts they use are made on site apart from pads and some screws from what I gathered. They had mini-arc welders that they used to tack the parts together before they did the silver soldering. I got to try the machine and it was very cool but I wasn’t very good at it. Oh well.

We were allowed to sort of wander around the factory floor much of the day and talk to the different people working. All of the workers do most of the different parts of the flute manufacture and rotate every so often. That seems like a good idea so people don’t get bored and when someone is out, someone else can take over a certain job if need arises. I got a chance to get my grubby fingers on some of the flute models in the show room, actually, holding those flutes might have been the most expensive things I’ve held as opposed to the silver rod, I’m not sure. Anyway, those flutes are just extraordinary: I can’t comment on the tone, I don’t play flute well enough to know, but the construction is of the absolute highest quality. Burkart uses a system called micro-Link to connect the keys to each other which is a system where there are no pins as there would be on most flutes. Visit their website to read about it because they can explain it better than I can, but generally I think the idea is to get a very tight feel with as little spring tension as possible. An added benefit would be that unlike on pinned key work, there are no pins to wear and eventually cause wobbly keys. That’s a guess on my part though so don’t quote me.

So it was a cool trip other than the fact that my junky car broke down on the way there, but that’s another boring story which I’ll spare you.

http://www.burkart.com/

 

The Beast

beast  beast3

 

beast4beast2

 

Here’s a tuba I just finished removing all the dents from. This tuba was a mess as you can see in the pictures. Apparently the kids at the school have named this tuba, ‘The Beast’. I understand the name: This thing was a full size tuba and it had been beat up very badly over the years. I had to take the beast completely apart to get at all the dents. It was a pretty tedious job but it turned out all right in the end.

The trumpet mouthpiece gap

When you put a mouthpiece into your trumpet, there is a space between the end of the mouthpiece and the lead pipe inside of the mouthpiece receiver. This space is know as the “gap” or by the more fancy name “annulus”. You can see the space below:

gap

The theory is that if you can find the right amount of gap, the instrument will perform optimally: Notes will slot better, the scale will be more in tune, and the horn will be more resonant.

Since every trumpet, mouthpiece, and player is different, there is no gap that will work best for everyone. The only way to find that sweet spot is by trial and error, adjusting the gap and seeing what works for you.

A simple way to test different gap settings is to wrap a strip of paper around the shank of the mouthpiece and insert it into the receiver. By adding more paper or taking paper away, you can adjust the gap. If you have too much gap, you’ll have to have metal removed from the shank. Once you do find the optimal gap, you can make the change permanent by having the mouthpiece altered.

 

Manufacturers failures continued

bustedsax

Pictured above is an all too common sight on modern horns: Brown discoloration beneath the lacquer that shows up after a while. I see this on low quality horns as well as the name brand pro level horns. My own Bach Stradivarius trumpet had this issue around the bell wire. This is what happens when you speed up production and don’t properly prep a horn before lacquering. Soldering flux is very acidic and if you don’t completely wash it off and neutralize it after soldering, you get discoloration of the metal and the finish. This can happen with repairs and it happens at the factory when the instrument is built. In this case, after the neck was soldered together with the neck tenon it wasn’t properly cleaned and they lacquered over the metal while there was still soldering acid on the joint. At first, the horn looked fine but after a while the acid reacted with the lacquer and produced this gross brown stuff. You can see how it’s spread out from the joint where the acid was concentrated at. This is easily preventable with proper cleaning and neutralization of the part before it is lacquered. Unfortunately, you can’t repair this issue without removing the original lacquer from the area and re-lacquering it, which in most cases isn’t worth doing. So you’re stuck with this ugly mess.

Ultrasonic cleaning and why it’s great

I love my ultrasonic cleaner. You should love it too. Here’s why:

Ultrasonic cleaning is a process where transducers, on the bottom of a tank of water and mild cleaning detergent, generate millions of microscopic cavitation bubbles with sound waves transmitted through the water. These bubbles get into every tiny space on the object you’re cleaning and gently remove the dirt.

The cleaning process is fast, safe for instrument lacquer and finish, second to none in quality, and environmentally friendly to boot. The only downside is that the machine is expensive…very expensive. But hey, that’s my problem not yours. You as a customer get all the benefits. It’s recommended that instruments, especially brass instruments, be ultrasonically cleaned and serviced once a year. This prevents build up of calcium and dirt which can rot your leadpipe and damage your valves.

I can’t say enough good things about ultrasonic cleaning.

www.davidfrostmusic.com