Bach C Slide bore discrepancy

[kramergfy]

I have an older Bach C, serial 40,xxx that has a 229 bell, CL bore on the valve casing, and was recently fit with a modern 25m pipe by the previous owner.

I noticed recently that the main tuning slide tubing appeared to be quite thick for a Bach large bore; I played a Bb 25L for over a decade, and know how thick the tubing should be, even on a standard weight horn. I took out the second valve slide, and compared it to the main tuning slide; it appears the second slide is a large bore, and the main tuning slide might be ML bore tubing! To confirm, I compared the C tuning slide to my Bach 37 ML Bb tuning slide (also serial 40,xxx, they are 200 apart), and the tubing appears to be the same on both slides, and both slides can fit perfectly in both horns.

So questions; is this a new thing with the 25m? or, do I simply have a ML bore C slide for my horn?
_________________
"I'm 73 and I'm still learning." - Maurice Murphy

Thread killer.

[J. Landress Brass]

It is nearly impossible to visually see .002" of difference on a tube. That is .001" difference per side. It is possible that the mail slide is from a ML but you would need calipers or pin gauges to measure.
_________________
Josh Landress
J. Landress Brass, LLC.
38 West 32nd Street, STE 908, NY, NY 10001
646-922-7126
www.jlandressbrass.com

[kramergfy]

Well, I don't have access to either of those tools at the moment, but I took another close look at everything in the daylight, and I honestly can't say for sure now. It's probably just that the ends of the C slide are just a bit more flush than the Bb slide, and thus looks a tad wider, or its just a newer/less worn slide. Anyways, thanks for chiming in Josh. The shirt I picked up from your shop 3 years ago is one of favs.
_________________
"I'm 73 and I'm still learning." - Maurice Murphy

Thread killer.