Week 14

This was a short week because of Thanksgiving break. But we did a lathe project to replicate a tuba valve stem. First my bench partner and I took measurements of the piece we were replicating. After that we used the tap and die and drill charts to figure out the correct size tool to use for this project. The stock material for this project was a 0.250 inch piece of brass rod. First I faced and de-burred both ends of the rod. Then I turned down one side of the rod for the male threads. On the last pass of the tool bit for turning I put the relief and shoulder to square off that end. Once it was the right length I used a 10-32 die to make the threads. Then I switched ends and faced the part to the correct length. When it was the correct length I drilled the hole for the inner threads. Then I tapped it with an 8-32 size tap. Once the threads were in I drilled the counterbore with a #18 drill. The counter bore allowed for the threads on the valve cap to fit in the stem because they are tapered near the base of the cap. After the ends were de-burred the piece was finished.

My worksheet with all of my calculations. Also the stem I was
replicating

Turning the end for the male threads

Using the 10-32 die to make the threads

Drilling the hole for the inner threads

Week 13

This was my last week on clarinets. I had to finish my project clarinet and even had time for an extra project that I did not think I would have time for. In order to finish my project clarinet I had to learn how to cork a tenon. To cork a tenon I used a #4 natural cork. I marked the cork according to width of the tenon and trimmed the piece. The strip that I cut I beveled one end so that the seam would be more cohesive. To soften the cork so that it is more pliable I hit it with my delrin hammer. This softened it and made it curve. To install the cork contact cement is used. When installing the cork a cosmetic thing to take into consideration is have the seam at the back of the clarinet by the thumb rest or opposite of the logo. This makes the cork aesthetically appealing. Once the cork is in place it is time to sand it so that the tenons will fit together. After the cork is sanded to the proper fit it is time to seal the cork. To seal it paraffin wax is rubbed on the tenon and then heated up to create a seal. This procedure is done twice. (Make sure when heating the tenon that you do not burn the cork, it is very easy to do) After the paraffin wax is melted the tenon cork is finished.

Old tenon cork

Cleaned tenon and ready for corking

Strip of cork cut for the tenon

Bevel on the end of the cork

Bump created where the cork overlaps

Sanding the cork to the correct size so the tenons will fit together

Sealing the cork with paraffin wax

Week 12

Key corking was the topic of this week. After the clarinet is padded it is time to put cork on the keys at articulation points and foot corks. When corking there are many different materials that can be used. The most common material is natural cork. Other materials that are used are composition cork, Valentino cork, Gummi cork, felt, leather, and teflon. People are experimenting with different materials everyday because they are looking for new material that will uphold the stresses put on it by the instrument. For instance on the low A-flat/E-Flat key the foot cork is usually in contact with a small surface. The small surface puts all of the pressure in one area which wears that cork out faster than the rest of the touch piece. Using a stronger material on this key is recommended so that the cork does not have to be replaced frequently.

The cork is contact cemented on to the key

Under the touchpiece

Rough trimmed cork

Fine trimming and adding the bevel

Finished key cork on the A-flat/E-flat key

Week 11

Padding! A clarinet pad is made of three parts: cardboard, felt and a skin covering. The skin covering can be made of a bladder, intestine or synthetic material. A pad can be installed with shellac or hot glue. NEVER, NEVER use super glue for gluing a pad. In order to pad you heat up the pad cup. When super glue is heated it produces cyanide gas. Before padding I cleaned the pad cups using a utility rag and denatured alcohol. When the pad cup was clean I heated up my glue and put it in the pad cup. Next I heated the pad cup so that the glue was warm. I then placed the pad in the cup. All of these steps were done with the key off of the instrument. I then installed the key on the clarinet to level the pad to the tone hole. Once the pad is floating on the glue I manipulated it to seal on the tone hole. With padding there are different issues that can arise. The pad may not be level (it is warped), tone hole is not level, not enough glue or too much glue. All of these factors determine how long the padding will take. Padding is a skill that I will get better with more practice.

Heating the glue to put in the pad cup

Heating the pad cup with glue in it so that it is ready for the pad

Week 10

This week I learned about key fitting. When working on keys it is important to take out end play and lateral play in the keys. This extra motion in the keys makes the clarinet feel sloppy to a player and can add extra noise. When fitting a key it is important to know if the key you are working on has a hinge rod with a hallow hinge tube or a solid hinge tube with pivot screws. When working with a hinge tube a rod the key is able to be swedged with a swedging pliers or a swedging collet. Swedging the keys thins the metal which stretches it and makes the key longer. This removes the end play. The lateral play, which is the movement between the hinge rod and tube, can be taken out with the swedging tools because it forms the tube to the rod. This takes up the space between the tube and rod and removes the lateral play. There are two main types of pivot screws: point screws and pilot screws. Standard point pivot screws have a pointed end and a head. These are nice screws to take out end and lateral play. In order to take out play I need to make the screw go in further. This is done by removing material from the post with a pivot screw counter sink.  Headless point pivot screws are the easiest to fix end play because the screw can be placed further in the key tube. Pilot screws are screws that have a cylindrical rod after the threads. There is no fix for lateral play but in order to fix end play washers need to be installed to fill the space.

Swedging collet tool. There are different size collets for
different sized hinge tubes

My clarinet screw board showing the different
hinge rods and pivot screws

Dent Roller

I had a question about what type of dent roller I used on trombone bells to remove bell dents.

Dent roller in vice

Placed in the vice with a V block

The ball bearing ring on the roller