I have an older Edwards Bass dual bore slide.
I am not sure if this is a recent issue OR has been there and never noticed before...
In playing position the upper leg has a slight wobble from side to side (left/right).
Obviously, it is more noticeable in 4th to 7th.
Is this a normal issue?
I love this side and hope to keep it that way!!
Upper leg wobbliness on dual bore slide
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Re: Upper leg wobbliness on dual bore slide
I am, probably like some others, wondering if you have the wrong outer tube on the top slide. It is very easy to tell with that model. Does the top outer slide fit on the lower inner slide? If yes, you have the wrong tube on the top.
If the top outer does not fit on the lower inner, then you should check the tolerances. You (or your tech) can measure the widest spot on the inner stockings and the inside of the outer tubes. The difference should be in the .011 to .014 inch. That is considered the normal tolerance range for a trombone slide. If the difference is more than .014, the slide could leak air and lack compression. If the slide is .010 or less, it will need to be super straight and parallel to have free movement. When the tolerances get down to about .007, it is nearly impossible to have great slide action (I have seen that on a few Chinese stencil trombones).
If the top outer does not fit on the lower inner, then you should check the tolerances. You (or your tech) can measure the widest spot on the inner stockings and the inside of the outer tubes. The difference should be in the .011 to .014 inch. That is considered the normal tolerance range for a trombone slide. If the difference is more than .014, the slide could leak air and lack compression. If the slide is .010 or less, it will need to be super straight and parallel to have free movement. When the tolerances get down to about .007, it is nearly impossible to have great slide action (I have seen that on a few Chinese stencil trombones).
Brian D. Hinkley - Player, Teacher, Technician and Trombone Enthusiast
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Re: Upper leg wobbliness on dual bore slide
Just for clarification....
When I say "wrong tube on top," I am not saying that you accidentally have your slide upside down. I am saying that your trombone was assembled with the wrong tube installed on the top half. I have seen wrong parts installed on instruments before......it definitely happens!
When I say "wrong tube on top," I am not saying that you accidentally have your slide upside down. I am saying that your trombone was assembled with the wrong tube installed on the top half. I have seen wrong parts installed on instruments before......it definitely happens!
Brian D. Hinkley - Player, Teacher, Technician and Trombone Enthusiast
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Re: Upper leg wobbliness on dual bore slide
The outer tubes ride on the stockings. The rest of the inner tube is a smaller outer diameter, so there is going to be a lot more play at the top of the slide where it isn't touching the stockings and there is room for the outer tube to move back and forth in relation to the inner slide. That is by design. If the whole inner slide were the larger diameter of the stockings, the slide wouldn't move easily. I wouldn't worry about it. If you are concerned that the slide compression isn't good, there's a "poor man's" compression test that's easy to do. Take the slide off the bell, plug both inner tubes with your fingers, hold the slide vertically a foot or two off the floor, and let the outer slide fall under its own weight. It should fall fairly slowly, taking a few seconds to hit the floor. If it falls quickly like it's freefalling, then your compression isn't very good. Make sure you have your foot underneath or some way to catch the slide so it doesn't slam onto the floor and get damaged.
Brad Close Brass Instruments - brassmedic.com
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Re: Upper leg wobbliness on dual bore slide
Thank you Crazy and Brad.