Some mods to a Bach 50B2

[Wilco]

Hi, just wanted to show you some mods done to a 50B2 I recently bought from Swissbone. Already a great instrument got even better. I had the triggers split, the rotors bored out and the inner tuning slide of the first valve shortened (inspired by a recent thread here). Valve section is a lot more open now!

[SwissTbone]

Yay! Nice work!

[bigbandbone]

Who did the modifications?

[Wilco]

Work was done by Gerd Kempkes, Bocholt Germany.

[Wilco]

Yay! Nice work!

Thanks! Really love how it plays

[greenbean]

Looks great!

[whitbey]

I had a C tuning slide made years ago that is a larger bore. So with both valves it blows a real easy low C. B and Bb are just in 2 and 3. Longer. I did this mod before dependent valves were more common on a horn I bought that was F/E. It made sense having C in first. All the sharp keys play easier. Horn plays down to 2xpeddle Ab clean.

https://drive.google.com/file/d/0B1izx3 ... OfI1MLgbqw

https://drive.google.com/file/d/0B1izx3 ... x_f0i7EjOQ

https://drive.google.com/file/d/0B1izx3 ... cZ8I1MdqDw

https://drive.google.com/file/d/0B1izx3 ... mE5Q3uPG6Q

[Wilco]

How much larger bore?

[JLivi]

Hi, just wanted to show you some mods done to a 50B2…the inner tuning slide of the first valve shortened (inspired by a recent thread here). Valve section is a lot more open now!

Would you mind linking tot hat thread? I must’ve missed it and am intrigued by the shortening of valve tuning slides.

[Wilco]

Sure: https://trombonechat.com/viewtopic.php?f=13&t=15674

[ithinknot]

Sure: https://trombonechat.com/viewtopic.php?f=13&t=15674

What Shires are doing on the lightweight wraps isn't exactly what you've done here. Cutting down the slide legs achieves a weight loss, but also introduces a bore gap in the left over length of outer tubing.

You could remove and shorten the outers too, make a pair of new ferrules from the offcuts, and then buff and remount the removed portion of the inner legs as substitute wrap tubing, but obviously that's more cosmetically disruptive.

[Wilco]

Sure: https://trombonechat.com/viewtopic.php?f=13&t=15674

What Shires are doing on the lightweight wraps isn't exactly what you've done here. Cutting down the slide legs achieves a weight loss, but also introduces a bore gap in the left over length of outer tubing.

You could remove and shorten the outers too, make a pair of new ferrules from the offcuts, and then buff and remount the removed portion of the inner legs as substitute wrap tubing, but obviously that's more cosmetically disruptive.

Yea… definitely…. Inspired is the word. Interesting comments about the Thein BVD valve section as well

[ithinknot]

Interesting comments about the Thein BVD valve section as well

Yeah... I don't doubt that they tried the 'no slide' thing at some point, but that's definitely at the 'ostentatiously impractical' level, and surely can't have made it onto many examples. The lack of tuning flexibility doesn't matter so much, but making a very dentable part of the instrument impossible to repair without fire is pretty obnoxious.

[dbwhitaker]

Repeating a question from above:

How much larger bore?

I'm also wondering if it's common to modify the second valve section to D? I've never done any modifications to my old 50B2 and am thinking about getting split triggers and somehow opening it up a little bit.

As an aside, I'm kind of surprised that Bach still makes the 50B2. I don't think this is the version I would chose if I was buying a new horn today.

[whitbey]

How much larger bore?

Sorry I missed this.

I have to guess. The notebook I wrote it in is lost. It feels like 0.020". It is more then the difference between a 547 and a 562 slide by a third.

[Wilco]

Repeating a question from above:

How much larger bore?

I'm also wondering if it's common to modify the second valve section to D? I've never done any modifications to my old 50B2 and am thinking about getting split triggers and somehow opening it up a little bit.

As an aside, I'm kind of surprised that Bach still makes the 50B2. I don't think this is the version I would chose if I was buying a new horn today.

I thought I wouldnt like the Eb tuning, but I dont mind at all. In ways it is even easier. You can tune it to match the F valved positions.

[Wilco]

How much larger bore?

Sorry I missed this.

I have to guess. The notebook I wrote it in is lost. It feels like 0.020". It is more then the difference between a 547 and a 562 slide by a third.

Thanks for making the effort to check! I am considering to have 2nd valve tubing made without a tunable slide. The tuning is now flat E (not E flat!). Which means the tuning slide allmost falls off to be able to tune to Eb. Anyway… future project perhaps…. I first need to play it at least six months or so…