A Glance at Trombone Slides

One recent morning, woke up at my usual five o’clock hour and started my routine. Fed the dog, made coffee in my big blue mug, sat on my sofa and settled in for a few early hours of writing, checking the news, and putting up Facebook posts on my business pages. I happened across a video of someone working on a trombone hand-slide and almost spewed my coffee. This person was smiling and talking while reaming the slide on an expander. I can still hear the skritching sound every time he shoved it onto the tool and yanked it off. I had to sit on my hands to keep from typing back in sheer alarm, “What are you doing? Stop that! No!”
Expanders have their place in the world of trombone hand-slide work, but it’s more of what I call a Hail Mary or last ditch effort repair, not the go-to technique. Hand-slide work is its own art form, and there are even technicians that specialize in this niche field. Specifically sized mandrels, double roller burnishers, flat stones and plates, special lights and sighting lasers, light hammer techniques with plastic heads designed for trombone work, flex-hones, polishes, cleaning rods, cheesecloth, the list goes on for tools and supplies needed for repairing trombone hand-slides.
Let’s talk about what the player and educator needs to know.
Alignment of the tubes is critical. The outer tubes must be straight and perfectly parallel in two planes, horizontal and vertical. The inner tubes must be the same and match the outer tubes. The tolerance or space between the two tubes is very small. Food debris, old crusted lubricants, wrong lubricants, tube bends, dents, skews, stocking stress, to name a few, can affect the efficacy of a trombone hand-slide. Some of these are simple fixes, some are more complex and require the attention of a repair tech.
First up is cleaning. I doubt there’s a trombone professional out there that would disagree that regular cleaning and lubrication of a hand-slide is necessary for good action. This can be as simple as a tub bath with Dawn dishwashing liquid and a flexible trombone snake. There is a plethora of different cleaning snakes for hand-slides, but my preference is one that has the flexible plastic, and not the metal coil. More protection for the inside of the tube and less likelihood of scratches. Slide swabs are available for drying or using a long cleaning rod and cheesecloth will work. If the second method is used, be sure to cover the entire rod with a thin layer of the cloth. Three reasons. One to be thorough, two to protect the interior from scratching, and three, to keep from losing a wad of cloth inside the tube. Some techs and players like to polish the inside of the tubes, and if so, the best polish to use is a water-based polish like Wright’s. Oil-based polishes, such as Brasso, leave a residue that is harder to clean out.
There are a lot of lubricants on the market, and my favorite one for students and professionals alike is Slide-o-mix Rapid Comfort. It’s a one-shot deal where the player does not have to go through a two-step process. A light misting of water from a sprayer is all that is needed to keep the slide moving smooth. Other lubricants are similar in nature. Slide creams such as Trombotine, Superslick, or Yamaha are applied lightly and then misted with a water spray. The water drops act as little ball bearings between the inner and outer slides. Regular cleaning and application of fresh lubricants will keep a hand-slide in top smooth action. How often? At least weekly for most players.
The other part of hand-slide maintenance can be extensive, as per the above mentioned repair conditions. Tube bends and small dents, even ones that are hard to see, can affect the hand-slide action. Students who place the slide crook on the floor and lean on it during class or break can bow the outer hand-slide tubes. Over eager players taking the instrument apart or putting it together can put dings in the metal by whapping the hand-slide into the bell rim. Unintentional taps against a music stand, tumbles from a chair during breaks, and the ever popular drill in marching band known as trombone suicide. I admit it looks cool, but I still cringe when I see it.
https://www.youtube.com/watch?v=eYl0vcaZQoM
A suggestion for beginning trombonists to assemble their instruments is to start with the slide straight up and down with the rubber bumper on the floor and to gently place the bell onto the receiver and let the weight of the instrument do the work. No extra pushing needed. It's common for young trombonists to hold their bell sideways in their lap and try to get the slide in horizontally...all while whacking the chair, stand, and kid next to them. Or, they try to assemble it with both parts in the air, which makes each part harder to keep track of and easier to drop.

The hand-slide’s feel can identify problems. Sandy, gritty, or sluggish, might only need a good cleaning. No matter what, the slide should be cleaned as this will eliminate one issue and help pinpoint any others. Always test with a clean, dry hand-slide. No lubricants, as they can hide problems. Test each tube set individually, and then together to zero in on the problem area.
If the hand-slide is still acting up, the problem is binding. A hard bind is when the action is jerky in one or more points. This means dents and no amount of cleaning will help. The slide will have to go to a professional technician who has the proper training and tooling to remove them.
A soft bind feels like a gentle hesitation. This is usually because of a stress bend in the tubing. This often happens when the student leans on the slide or drops it. A small rubber bumper on the guard tip acts as a shock absorber to help, but it may not be enough. Larger crook

protectors are available and show a lot of promise, but if enough force applied, the tubes will bow outward.
A straightforward way to figure out where and how bad the bends are, is by sighting. Place a vertical plumb line of black electrical tape on a white wall surface. Hold the slide perpendicular to the tape and look down the tube. There will be a thin black line reflected on the tube that will clearly outline where the bend is. Check two positions, tube side by side and vertically. It takes time to sight accurately, but it is possible. A simple single curve bend might be something the player or director can straighten, however it’s still a better idea to visit the repair technician.
Smaller or complex multi-curve bends will have to be sighted by a professional against a stone or plate designed for that purpose.
There comes a time, when a hand-slide has been worked-dented-beaten-straightened-hammered-twisted or so full of dezincafiction spots (red rot), it’s time to retire it or rebuild. Depending on the condition of the rest of the instrument, it may be more economical to get a new one.