Trombone Slide SPL
(Straighten, Parallel and Level)

Part 4
Inside Slide


Sighting down the outside length of the inside tubes aids at detecting imperfections such as dents, creases or warping. Inside tube damage is not as common as that to the outside tubing but it is very important that it be addressed.  No matter how straight the outside assembly is, the slide, as a whole, will not work at its best if one of the inside tubes remains distorted.


On this instrument, one of the inside tubes was damaged to such an extent that it required unsoldering from the cork-barrel in order for the proper repairs to be made.


The inside tubes can at times be very stubborn.  Mandrels, burnishers, mallets and so on are used but the skill of the repair technician is what really gets the job done.


Now that the inside tube is straight, the cork-barrel is mounted onto its respective tube. It is important that the tube be centered or the screw lock will catch on the end of the outside tube in addition to causing problems with the inside tube's proper alignment.


For this process we use a set of three spacers that center the cork-barrel on the inside tube. Using the outside tube to evenly wedge in the brass spacers, the cork-barrel is made to center perfectly on the inside slide tube.

Cork Barrel Spacers, Ferree's Tools Part No. G35


Once the inside assembly is fitted together, and appropriate adjustments made, it is carefully soldered together. Then it is ready to be polished, cleaned and prepaired for spot lacquering.

Part 1 - Evaluation and Preparation for Repair

Part 2 - Cleaning and Dent Removal

Part 3 - Assembly and Soldering

Part 5 - Polishing, Lacquering and Completion



Copyright 2004 Oberloh Woodwind and Brass Works