Hand Slide alignment on a trombone is crucial to the performanceand feel of the slide. A properly aligned slide will also produce a better"seal" over the entire length of the tubing. Straight tubing also wears evenlycausing the slide to last much longer.With a little practice, the properalignment and straightening of the hand slide can be done in a very shortperiod of time.
After disassembling the slide, check to see if there is any residue onthe stockings (expanded end of the inner slide tubes).It is important thatthe slide be perfectly clean and free of dirt before proceeding withstraightening. A white residue usually indicates dried silicon. This canbe removed with "Brasso" or any other commercially available brass or nicklecleaner.It may take some time to remove this residue since it is often timesvery dense.Polish the rest of the inner slide with any good metal polishwhich will leave no residue.
You will have to purchase a trombone cleaning rod to adequately cleanand polish the outer slide. Once you have acquired a cleaning rod, cut piecesof cotton which are of a length slightly longer than the cleaning rod.Pusha piece of the rag through the eyelet at the end of the rod. Make surethat the piece that runs through the eyelet will not easily come out. Drawthe rag along the length of the cleaning rod and hold it taunt at the oppositeend. Apply "Brasso" or other brass polishing product to the rag at the eyeletend.Insert the rod into the outer slide and work the slide in and out untilno resistance can be felt.Be sure to bunch enough material at the eyeletend of the rod so that the material is coming in contact with the inner partof the slide throughout the entire stroke.Be careful not to pull backon the rod without first pulling back on the material.You can get the ragjammed in the outer tubing very easily by pulling on the cleaning rod andwedging the fabric at the end of the rod in the tube. This can be extremelyhard to correct! Once again, keep cleanimg until no resistance can be feltin the tubing.Once all the cleaning is finished, you can move on to straighteningthe slide.
To straighten the slide you must first find a light source which you canuse too sight down the slide. I prefer using a flourescent light fixture.By standing at the end of the fixture I can sight down the length of thetubing by holding it up in line with the flourescent bulb. The reflectionfrom the bulb will reflect a straight line of light along the length of theslide.By observing this reflection I can determine where the bends are inthe slide.This can be done with both inner and outer slides.To straightenthe slides, place the end of the slide on a table about waiste high. Usinga clean rag, push gently down on the slide while moving slowly towards theouter end.Where ever there is a "High" spot, straighten the tube by gentlyapplying pressure while moving along the length of the slide.It is importantto use only the pressue necessary to remove the bend. If you have any questionconcerning the proper amount of pressure, take the instrument to a trainedtechnician.It is incredibly easy to destroy a slideby pushing to hard.Thesame process is used for the outer and inner slides. After you have finished,clean the slides once more as described above.It takes alot of practice toget good at this one so don't lose hope if you aren't successful the firsttime out!