Custom carbon fiber modifications

Custom carbon fiber modifications for your horn

We can modify any horn with a new interchangeable carbon fiber bell. Our available bell sizes are 8″, 8.5″ and 9.5″. The most popular mods are for bass trombone as it “changes the game” with a dramatic loss of weight.

We can now add CF mods to one of the most popular horns, the Bach 42. We can make your bell interchangeable with our CF bell and also build a complete slide section with our curved brace and interchangeable lead pipes.
Email us your idea for quote and availability. The all up weight of the 42 with our mods is 3 lbs. More importantly it moves the weight just on your shoulder and reduces all the weight on the ends.

  • Carbon fiber bell (8″, 8.5″ and 9 1/2″)
  • Carbon fiber two piece cut bell with aluminum or standard brass threaded rings.
  • Detachable CF bell with interchangeable original brass bell (standard fittings are Edwards style)
  • CF outer slide for all make and models. (see slide page)


3B Carbon fiber two piece bell with threaded rings

Kevin Jones, FSU jazz trombone professor.



CF removable bell section and tuning slide and outer slide for Yamaha bass trombone

These modification were done to Doug Yeo’s Yamaha bass trombone. I have included a link to his blog post/review.

Doug Yeo, former bass trombonist with the Boston Symphony Orchestra

“To say that I am enthusiastic about what Dave Butler has done would be a profound understatement. My new carbon fiber parts as installed on my YAMAHA YBL-822G bass trombone have given me an instrument that is highly responsive and lightweight but has a sound I would expect to be produced by my fully brass and nickel bass trombone. Dave Butler’s work with carbon fiber will allow me to continue playing the trombone for many more years as a result of the instrument’s reduced weight and great responsiveness. We are witnessing one of the most significant developments in trombone design and manufacturing since the invention of the F-attachment in 1839. This is not an exaggeration; of this I am quite serious. The future is now.”

To read Doug’s entire blog post go here: The Last Trombone

Douglas Yeo, bass trombone YAMAHA YBL-822 with carbon fiber bell, main tuning slide, hand slide by Butler Trombones
Sangmi Lim, piano
James M. David: “Southern Gothic” from Three Imaginary Landscapes Recorded at the South Texas Brass Symposium, Del Mar College March 2, 2019

Michael Nelson 16M conversion. Horn Heads (Prince’s former horn section).

I’m really diggin’ my 16M w/Butler carbon fiber slide and bell flair. This show was it’s first trial run right after I got it. I think it’s going to be my go to funk horn.

Hear Michael play this horn: (btw aside from hearing Michael play this horn, this is a GREAT show!!!)