TromboneChat

There seems to be a wide variety of stocking profiles among older horns. My stock Elkhart 88H and Corp Bach 36 have stockings that appear as a constant diameter, while most of my newer horns have more barrel shaped stockings.

Is there a reason for the change? Also, when we order replacements, is there a way to get the old-style straight stockings?

Many barrel shaped stockings are actually drawn into the inner slide. Very old horns will have soldered on stockings. Somewhat newer instruments will have drawn cylindrical stockings.

I believe barrel-shaped stockings were adopted because they were easier to refit the outer slide on when you take it off. There is little practical difference in seal between a barrel shaped stocking and a cylindrical stocking so replacing a cylindrical with a barrel shouldmake little difference.

I'll leave it to those who know to say whether you can order barrel vs cylindrical stocking inners.

BGuttman wrote: ↑Wed Nov 24, 2021 12:37 pm
There is little practical difference in seal between a barrel shaped stocking and a cylindrical stocking so replacing a cylindrical with a barrel shouldmake little difference.

This isn't quite true. Modern Bach slides (since 2014 or so) have the new barrel type and seal much, much worse than previous designs.

Burgerbob wrote: ↑Wed Nov 24, 2021 1:18 pm

BGuttman wrote: ↑Wed Nov 24, 2021 12:37 pm
There is little practical difference in seal between a barrel shaped stocking and a cylindrical stocking so replacing a cylindrical with a barrel shouldmake little difference.

This isn't quite true. Modern Bach slides (since 2014 or so) have the new barrel type and seal much, much worse than previous designs.

Is that the shape, though, or did they decrease the diameter at the same time for sloppier/easier tolerances?

It's like small Holton/Martin Urbie slides (dunno about the basses) - great action, BIG tolerances, basically no seal.

ithinknot wrote: ↑Wed Nov 24, 2021 1:26 pm

Burgerbob wrote: ↑Wed Nov 24, 2021 1:18 pm

This isn't quite true. Modern Bach slides (since 2014 or so) have the new barrel type and seal much, much worse than previous designs.

Is that the shape, though, or did they decrease the diameter at the same time for sloppier/easier tolerances?

It's like small Holton/Martin Urbie slides (dunno about the basses) - great action, BIG tolerances, basically no seal.

It may have been changed again, but a bit of both I think.

If google is queried with “Yamaha,” Yamaha claims that the barrel shape reduces friction. They say contact is reduced to a “line.” Perhaps they mean a thin torus.

Olds made the same claim of reducing friction with fluted slides. King craftsmen were grinding a slope at the transition from the primary tube diameter to the stocking diameter. The reason given was that a sharp edge scrapes all the lubricant from the outer slide. The grinding was said to be tribal knowledge. It was not documented as a requirement on the drawing early on.

When we see wear, for example on vintage Conn slides, it seems to be more often at the top or bottom of the slide stockings. It makes sense to go ahead and provide some relief at the get-go.