Week 18- Flute PC, Clarinet Post Replacement

With a four day week, I still got a huge amount of work done in a short amount of time.  While the class was finishing up our work on clarinet and flute play conditions, I was also working on the rosewood clarinet with my teacher, Lucas.  I want to do all the work necessary to make the clarinet a great show and tell piece.  This week we were completing the key fitting on the upper joint.  Two posts (the Side Bb/Eb and Register Key were stripped.  Because the instrument is not standard, we didn't have a nickel silver post without lacquer to replace the current posts with.

I began by drilling and tapping a nickel silver rod.  The original diameter of the rod was .157".  This rod was tapped to the measurements of the original post.  After checking to see if the original hinge rod fit in the new nickel silver rod, I moved on to the post work.

By hand, I drilled into the post face.  It was important to drill only 75-85% of the way through the post face. This was for two reasons: to protect the cosmetics of the visible post face and to act as a stop for the new nickel silver insert.  Here, I used a #42 drill bit which measure in at a diameter of .0927".

Returning to the lathe, I turned the outer diameter of the nickel silver insert to a diameter as close to the drill bit used to drill the post.  After turning to .0930", I removed the rod and hand filed the insert to size on a bench motor.

After filing to size I double checked the fit in the newly drilled post.  There was a tight fit as well as excess rod to ensure some room for filing once the insert was set in place.

With a jeweler's saw, I cut the insert off of the nickel silver rod.  After this was complete, I created an oversized hinge rod with which to ensure a tight fit in the hinge tube opening post.  The diameter I chose for this was .081" as opposed to the original hinge rod's diameter of .077".  The reason we used the oversized hinge rod only for fitting purposes was because the original hinge rod fit well to the hinge tube of the key mechanism.

Threading the bushing onto the oversized hinge rod, I checked the fit of the insert in the drilled post.

Starting with the Side Bb/Eb post, I used Red LockTite to act as the fitting glue.  Lucas and I decided against epoxy because of the pressure that could potentially be placed on the bushing when threading and tightening the hinge rod into the insert.  I applied grease to the threads on the oversize hinge rod to ensure that any LockTite that touched the threads would not lock the threads in the bushing.  After waiting overnight, I released the oversize hinge rod.

After repeating the process with an additional insert on the Register Key, I was left with a bit of filing to ensure that the insert was flush with the post face.  Each key lost a considerable amount of lateral play as a result of the well fitted hinge rod.

After the key fitting was taken care of on the upper joint, I machine buffed the keys and hand buffed the posts on the body.  As seen in the picture below, the clarinet is becoming quite a work of art.  As the restoration takes place, I will be interested to see just how much work the clarinet needs.  I am not out of the woods yet.  There is considerable work to be done on the lower joint, including fabricating a grenadilla insert for the upper tenon of the lower joint.  MAKING part of a clarinet is too cool.  I can't wait to see how it turns out!