Bach-o-rama

[arpthark]

I drove out to Cape Cod very, very early one morning to grab a bundle of Bach USA tubas in various states of repair. I think between the three, I have enough working parts to make two viable instruments.

Two are simply labeled “Bach” and the other one (which will be the donor instrument) is a Mercedes/Vincent Bach. I think the bell diameter on the Mercedes is just a bit larger than the others.

The good news is no holes in the bells, and the valves are all in good shape. The worst things were misaligned pistons jammed into their casings even though the valve guide was not lined up. I tapped those out gently using a piston of the same diameter and a rawhide mallet. One piston was slightly out of round on the bottom “skirt”, which I tapped true using a dent ball and hammer.

I seem to recall that these were just different enough from the Olds/Reynolds versions that parts aren’t compatible? Threading or something being a bit different somewhere? I need a bottom valve cap and a couple finger buttons.

They play quite well, little punchy 7/8-ish sized things. I should have them ready for sale within the next couple weeks.

[bloke]

The pistons diameter on these is a little bit too large to fit Olds / Reynolds without an inordinate amount of labor to make them fit Olds (which I believe was by design, to discourage people from buying Bach parts to keep Olds tubas working) and my observation is that the actual un-plated piston bodies on the Elkhart pistons is indeed a larger diameter, yet the nickel plating they put on them was apparently thinner, because - even though all of the Bach/Elkhart instruments were made later than all of the Olds/Reynolds instruments, the Bach ones - more often - show more plating wear. I'm not saying that the plating was crummy. I'm just saying that it was thinner. Back in the '50s and '60s, Conn and Olds put super thick nickel plating on their pistons, which is why they often still look great today, yet they're not particularly tight anymore.


I believe Allied Supply, finally, is sold out of replacement Bach pistons.

Everything else is pretty much interchangeable.

I like to use Bach/Olds top caps on King valve sections that I incorporate into instruments with King valve sets that I build for myself (threads are the same for Bach and Olds and also the same as King), because Olds caps feature the classic look, and also the center riser on the Olds caps is 1/8 of an inch lower than with King, which means that King valve stems (with Olds top caps in place) can be trimmed down 1/8 of an inch shorter, for more comfortable hand position (same valve stroke, just lower button position).