TromboneChat

I just acquired a Bach 42B with a 6.5AL mouthpiece. I love the sound with this cup depth/ throat/ backbore combination, but I wish the inside diameter was bigger. Is there anything off the shelf that fits that description?

Send it to Doug Elliott and have him thread it for his rims.

A 5GS would be a good starting point.

Greg Black has versions of this piece up to a 3rim..

I really like the Hammond 13ML. Feels on the bigger size for a 6.5 sized piece, but, for me, still felt like a 6.5 vs like a 5gs, which feels like a smaller 5g (if that makes sense?)

Depends on how much bigger you want the cup diameter.
As Bach 5G pointed out, Bach has already provided one solution (same throat & backbore, similar cup, larger rim):
Bach 6½AL: Cup I.D. = 25.40mm (nominal); Throat = 6.63mm, Backbore = #420
Bach 5GS: Cup I.D. = 25.50mm (nominal); Throat = 6.63mm, Backbore = #420

Lots of other options suggested here. Don't ignore Marcinkiewicz mouthpieces, such as
Marcinkiewicz 5G: Cup I.D. = 25.55mm (nominal); Throat = 6.63mm

Nearest Doug Elliott equivalent is probably LT F Cup / F8 Shank (6.63mm throat), with a Rim of your choice, such as LT101 (25.65mm I.D.), LT 102 (25.91mm I.D.), LT 103 (26.16mm I.D.), or LT 104 (26.41mm I.D.).
Customized to your preference!

Just saw this, if you're interested:
viewtopic.php?t=30478

My fairly new D+ cup is the depth of a 6-1/2, and I have it in all of my tenor series. Rims up to XT 106 (2G size) but I doubt you want that big. I have been using it with an N104 rim, on a 2B and 36B.

I also have a new D+8 which is a large shank for it.

I think I'll start with the 5 GS. If that doesn't get it done, I'll try a DE setup. Thanks everyone that gave suggestions.

Elow wrote: ↑Tue Mar 07, 2023 10:37 am Send it to Doug Elliott and have him thread it for his rims.

That may be step 2 or 3