Week 17- Making Bearing Seaters and Set Screws

This week begins the spring semester.  I was so happy to get back into the repair shop.  My class is working in the woodwind repair shop for the next 8 weeks, and our first tasks this week were play conditions on clarinet and flute.  I have finished the play condition on my clarinet.  I needed to replace a pad, lower the ring keys, and reseat a few leaking pads.  All in all, the clarinet shaped up to be a reasonable task.

The flute play condition is still in the works, however.  There is a lot of work to be done on making pads seal.  While this may not seem daunting, being out of the woodwind lab for 11 weeks makes padding look like a big problem.  However, I am confident that I will be able to have the flute completed by the end of next week.

We had a lathe project this week to create a bearing seater.  This will be used when I return to the brass workshop.  Using a drill bit to create a half inch hole in one end and a drill bit, and tap to thread the other end, the project was done before I knew it!  See the picture below for the finished product.

Another project I worked on this week was specific to the rosewood clarinet I mentioned in an earlier posting.  I am returning to this instrument to finish the key fitting before I can move on to padding, corking, and tenon cork installation.  The interesting thing about this clarinet is that the pivot screws are Conn style pivot screws.  This means there is a tiny set screw that locks the pivot screw into place.  The rosewood clarinet had nine pivot screw points, but only two remaining set screws.  After realizing that there were no replacement parts that matched my set screws, I had to make the screws for the clarinet.

I began by finding a piece of steel rod that matched the outer diameter of the set screw I had to reference. The rod I chose was 0.072".  I used a 1-64 die on a bench motor to thread the steel rod.  The picture above is the portion of the rod that I threaded.

I then made a collett to hold the steel rod while chucked in the bench motor.  Because I was cutting the steel stock to about 1/32", there was little to no way to grip the new set screws to cut a slot in the face of the screw.  So I used a tap at 1-64 to create a holder for my steel rod.  I used a jeweler's saw to cut a slot in the collett to ensure that I could get a tight grip on the chuck when cutting the screws to size.

I used a portion of my threaded steel rod to act as a stopper in the brass collett.  This way, when I threaded the other portion of the steel rod into the opening, the screw length was determined by the stopping point in the collett.

 Following one 12 minute attempt at creating a set screw, I was able to produce one screw every three minutes.  By method was time effective and the rosewood clarinet is one step closer to have its key mechanisms fitting properly.  Below is a 0.072" diameter screw at a length of 1/32".  It's incredible to work with something so small and have such a form fitting and successful end result.  Next week I will be making oversized hinge roods for some of the keys with extreme lateral play... Until then!