Bassoon Overhaul

Proper care of your instrument ensures a long service lifetime and a minimum of problems that require more expensive repairs. A yearly overhaul of a bassoon is generally regarded as regular routine maintenance and is widely recommended, especially for older instruments. My overhauls typically include: cleaning the body and keys, oiling the bore, regreasing all the moving parts, and inspecting pads, springs, and almost every other bit for wear or indications that they may need to be replaced. Year to year, it's unusual that something needs to be replaced, but it's good to keep an eye out and fix a problem that could spring up during a performance or find gradual wear or damage indicating a bad habit which can be fixed before it becomes a real problem. I like to do my overhauls in the spring, it's typically the end of school or an orchestral season and the air is not too dry as to need (and eventually release) extra bore oil.

I am not a bassoon technician, but I have been doing this yearly for a while now. With a basic set of tools, some comfort working with your hands, a good understanding of your instrument, and someone with experience watching over your first overhaul, it's fairly easy to perform all of the required regular maintenance yourself. Doing the work yourself makes sure that it happens regularly, saves a lot of money, keeps your keys quieter, and can prevent virtually all of the potential problems that your instrument can have, short of acute incidents. This page won't go over every step, and just as I wouldn't recommend that a first time student read a book and figure out their first scale entirely on their own, I wouldn't recommend performing your first overhaul alone – find someone who's done it before and who can keep an eye on your work to make sure you're doing things correctly. Doing it yourself with oversight will make it easier to repeat on your own, and having someone who can catch mistakes, recommend techniques, or keep track of which part goes where can be invaluable until you have done it before.

 

Tools

When overhauling, I generally use:

2 flat head screwdrivers, one 1.5mm head, one 2.5mm head – if you buy a set of small screwdrivers, there will generally be two of appropriate size, but you will need a larger one (for pivot screws) and a smaller one (for rod screws)

A spring hook (though you can get by with the two screwdrivers if you're crafty and careful)

A bocal brush or other tone hole cleaning brush

Grease – either one designed specifically for use on wooden instrument keys or green molybdenum grease (commonly CV joint grease in an auto parts store) . I do not oil my keys because grease lasts so much longer, but is is CRITICAL that you get the right kind of lubricant. Mixing oil and grease is never a good idea because it doesn't generally work well, but using the wrong kind of grease (like white lithium) can damage your keys, finish, or both.

Bore oil – I use a light mineral oil, it was fairly difficult to find, but often repair techs will sell their oil (or blend of oils) if you need to find some. Some options are discussed here

Paper towels

An open, stable table covered with a cloth that can get dirty

A natural fiber (cotton) polishing cloth

A silver polishing cloth, preferably quite large (more than a square foot)

Cork grease

Time – you will need several (at least three) hours the first day, then will need to let the instrument sit, disassembled, overnight for at least 12 hours, then you'd need to spend at least another three hours reassembling it. You won't be able to play on the instrument in this time because it will be in pieces.

If you come across something that is damaged, worn, or just needs to be replaced, there could be more parts, knowledge, and tools needed than fits the scope of this page, but especially if overhauling for the first time, additional things may be needed (another reason to have an experienced repair person nearby when doing your first overhaul).

The basic steps of the overhaul are pretty simple, and each individual operation is quite basic, but all of the steps together add up to a considerable amount of time, effort, and overall complexity. Essentially, you disassemble the instrument, you clean the body and all the parts, you oil the bore, and you grease and reassemble the instrument. There is a little flexibility in what order your do things, but there must be a delay between oiling the bore and reassembly to keep pads clean.

An horn in need of cleaning

 

Disassembly

Disassemble joints one at a time and keep them separate on your table; I like to put the keys on one side of the instrument on one side of the joint they belong to and the other side's keys on the other side of the joint when laying it out on the table. I also try to keep close keys close and keep them facing the correct direction up or down the instrument. When you have a key with a rod screw, take the screw out to remove the key and reinsert it into the key off the instrument to keep them together – if you mix them up it will be trouble when you reassemble everything. For pivot screws, back one them out until you can remove the key, remove the key, then just screw it back into the post to keep it in place. If you leave one in place you only have to re-tighten one and you can work around a potential stuck screw. All pivot screws are not created equal, so do keep the right ones in the right spot.

All of the keys come off before the bore oiling

As you're removing keys, you'll notice that some can't be taken off without others being already removed and that some need to be maneuvered in specific ways to be taken off - take note of this because it will make reassembly easier. This is especially true for the four plastic pins that run through the boot joint to connect keywork on either side – they are of slightly different length and if the wrong one is put back into the hole it may not close fully or may not allow the key to be fully depressed, so keep track of which goes where. Be careful when using your screwdrivers, if you slip off of a screw you can easily mar the finish of your instrument or even the keys. The best way to avoid slips is to work slowly, keep one finger next to the head of the screw to keep the screwdriver from sliding out of place, and to keep the screwdriver in a comfortable position in the hand, ideally in line with your lower arm, so you can have maximum control over it.

To oil the bore, the U-tube must also be removed, to do this you take off the cap on the end of the boot and remove the nuts that hold the u-tube plate in place. Now you want to pull off the u-tube, but gently. My preferred method has been using a screwdriver against the cork gasket, NOT pressing into it, but putting it in place horizontally, then rotating it until it presses on both the u-tube plate and the cap on the other side of the gasket, pushing the two gently apart. It is important that you do this carefully because the cork gasket can rip when removed, especially if it's been a long time since it was done – if this happens, you would need to remake a new gasket. Making a gasket is as simple as tracing and cutting out a new one in a new piece of cork, but it requires considerably more tools, work, materials, and care, as leaving ragged edges on the holes for the bore will effect the sound of the instrument. If you're careful and it's not too brittle, it can be removed intact and this isn't a problem – when you reassemble the horn you'll put on a generous amount of cork grease which should make future removals easier. The gasket must come off on the u-tube side, as if it gets bore oil on it in a later step, it will need to be replaced, but the gasket is typically cemented to the u-tube plate and will come off on the correct side.

 

Cleaning

Cleaning everything is the simplest and most time consuming step. You start with the body of the instrument, first with a soft cloth to remove extra grease from the keys and screws which are now removed. Following that, you clean the finish of the instrument with a cloth to remove any grime stuck on the finish. Then I go through the smaller tone holes (specifically, the ones on the lined side of the instrument (the wing and the smaller bore of the boot) with a bocal brush or tone hole cleaning brush to scrub the grime out of the tone hole – just be careful not to push into the bore too far because it is possible to scratch the liner opposite the hole. If in your scrubbing, a piece of plastic in the shape of a straw with a cut in it comes out, make a note of it and reinsert it when reassembled – this is an easy-to-undo modification which slightly lowers the pitch of notes that sound through that hole – if you leave it out, your instrument will be voiced differently. It's worth mentioning in this section that bassoon needle springs are sharp, so be very careful when cleaning the body of the instrument - stray polishing can draw blood and just winging a spring can bend it enough the make a significant difference in key press strength when you reassemble it. Do NOT use any chemical, cleaner, or water to clean your instrument, between the finish, the silver, the oil, and the raw wood, there are no cleaning agents which are safe to use on the body of your instrument, don't do it.

What a difference a good polish makes

Next, when the grime is removed, you can use your silver polishing cloth to clean the tarnish off of posts, bands, and other shiny pieces. You don't want to use this cloth on the finish of the instrument as it is treated with chemicals, but I've found that as long as you're avoiding contact it should fare fine. Do NOT use a liquid silver cleaner and regular cloth, they are often much more powerful and because they are liquid, can (and will) get on other parts of your instrument, damaging them.

Next is cleaning the keys, and this is straightforward. Clean off the excess grease with a soft cloth, then use the silver polishing cloth to clean off the tarnish. For keys with rod screws left in them (you did that after taking them off, right?!), put the rod aside, wipe the grease off, polish the key, then reinsert the rod. If you don't wipe the key off after removing the rod, you'll get grease on your silver polishing cloth and if your keys are like mine, even a large cloth will be completely used in the course of an overhaul. There are a lot of keys so this will take a while. If you're running short on time in the first day but can spend time on the second day, you can clean the instrument body, bore oil, then clean keys the following day before reassembly.

 

Oiling the bore

With the keys off, the gasket removed, and the body cleaned and polished, you're ready to oil the bore. If this is the first oiling in a while, the instrument may soak up a lot of oil, but if done regularly, a single application is plenty. Start by applying your bore oil to some paper towel either folded over or wadded a bit, make sure that it is 'damp' but not dripping. The paper towel, wadded up, must be small enough to fit through the bore of the joint you are oiling, the bell being the largest, the long joint being in between, and the larger unlined side of the boot as the smallest. Use the dowel to gently push the oiled paper towel through the bore (largest to smallest diameter or opposite of the direction of air when you play) several times. A tighter fit will apply more oil through each pass but will be more likely to get stuck. If it does get stuck, do not force it, just turn the joint over and push it out the opposite way. You should be able to see where oil has been applied inside the bore if you hold the joint up to a light, so continue until the inside is fully covered. Remember: do not oil the bore of the lined joints (the wing and the smaller side of the boot) and do not apply so much oil to the cloth that it drips. If this is the first oiling in years, it's probably worth waiting a bit (10-30 minutes) and repeating the application.

Once the inside is oiled, you want to apply a coat to the outside of the instrument. I generally use paper towels for easy clean up, but because of silica in paper products, they can make very fine scratches on your finish – it is advisable to use a soft natural fiber cloth, though I haven't noticed a degraded finish from using paper towels for several years. While there is no advantage to oiling the metal bands or the bell ring, there isn't a problem with getting bore oil on them and it ensures that the wood adjacent to them is properly treated. The only thing to keep from oiling is the string or cork that stabilizes the joints between tenons – apply oil to the wood of the tenons, but keep it off those stabilizing and sealing bits. Applying oil to a lacquered finish isn't as useless as it seems – there will be openings for the oil around posts and other places, there will be tiny cracks that let it through, and there is some limited permeability of most finishes, so the oil can eventually penetrate through what seems like a solid protective shell.

After applying the oil to the outside, wait about half an hour, and use a soft cloth to clean up the excess, doing the same with the interior of the bore. It will still feel oily and you will wipe it down once more before putting keys back on, but much of this will soak on in the waiting period, which is the next step. Wait at least 12 hours from oiling your bore before putting keys back on or you will be oiling your pads as well – which will damage them.

 

Greasing and reassembly

After waiting 12 hours from oiling and cleaning the keywork, you're ready to put the horn back together. Before anything goes on, go over the body of the instrument with a soft cloth again to remove any remaining bore oil. Pick the joint you want to start putting back together and grab your grease, I like to start with the boot. If you have your keys arranged on the table right, it should be fairly clear as to what goes where, but generally only the right key will fit. You will also have an idea of what the lowest layer of keys are from your notes or your memory – since some lie on top of others you need to install the bottom layer first - that will generally be the opposite order as you removed them.

Cleaned up and reassembled, at almost 70 it plays just like new!

For keys held on by pivot screws, take the larger screwdriver and get some grease on the end, use it to pack the end of each key – the conic hole where the pivot screw will fit - with grease and then install it reverse of how you removed it, loosening the same screw you removed to get the key out. For rod screws, remove the screw and dip/rub it in the grease, then put it back in the key, turning it around. Repeat this until the feeling of turning the screw in the key is smooth and viscous, the first time or two you will likely feel metal-on-metal contact when turning it, but when it's smooth, there's enough grease in the housing to keep it lubricated. Then remove the screw and install it on the instrument, reverse of how you initially removed it. When installing keys, it's important to consider attached springs or springs that will be acting on the key – you can often engage the spring as part of the installation saving yourself some work with a spring hook later on. There are also some thicker wire springs that don't have enough clearance to fit under the spur they engage on, so it's important to get them on the correct side of the spur before the key is screwed into place. If you end up with it on the wrong side, you can always take it off and reset the position, but if it takes a while for you to realize and you have other keys on top of it, removing it to fix the spring placement can be a considerable back track.

Regarding the plastic pins in the instrument, once one side of the boot's keywork is on, you can put them back in their respective holes, but if you tilt the boot they can still slide right back out. You can also wait until installing the key that will hold it in the instrument to make sure it doesn't fall out, whatever your method, make sure they're in the right place. It's also worth mentioning any plastic inserts into tone holes that were removed should be put back in before the keys go on. Like the springs, it's an easy to fix if you miss it, but it can take a while to open the hole that you need to change when it's under a few layers of keys. If your keys have rollers, you can remove the rollers just like rod screw keys and grease them in the same way. They generally need regreasing most often, because there is more play around the screw than a normal key, but they can easily be removed and regreased when needed. Though I mentioned rollers here, to be sure that they're cleaned under, I like to grease rollers as part of the cleaning step before reassembly.

When the keys are on, the springs are engaged, and everything looks nice, you should be ready to play.

 

Playing test

It's important to play on it fairly soon after, not because time is of particular concern, but because you want to check your work. Play through a chromatic scale on a familiar reed and make sure the key action feels smooth (it will probably be firmer and smoother than before), make sure keys pop up when they should, make sure everything is quiet, etc. If a pin is in the wrong place and a key isn't closing, you'll be able to tell quickly. If a spring is disengaged you'll feel it or the key may take too long to close, something you can hear when changing notes. If something isn't sealing, it will be obvious in the low register. Continue trying things out until you're satisfied with your work. From there, you can treat it like any other and play or pack up as you like, there are no particular playing restrictions after an overhaul. It is normal for some grease to come out around key ends and you should clean it up before it gets on your clothes. It's also normal for the instrument to feel waxy on a humid day – this is a small amount of oil coming out of the wood with the change of weather.

Enjoy your freshly overhauled instrument! Keys won't clatter, problems generally won't come up, and everything will be shiny and new looking. If you have additional questions, run into problems, or just want to learn more about bassoon repair in general, there are a lot of resources online. These should only supplement apprenticing or leaning from an expert, but they can be useful information and can give you ideas of what you can do and what should be left to an expert. A good place to start is Fox's Technician resources

Especially when you're doing this the first time, make sure to have someone to supervise your overhaul and make sure to have a repair-person who you can contact if something goes wrong or you find a problem you aren't qualified to fix.

 

 

May 22, 2014

 

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