Case Study
The Ascender

Band on the run

Life on the road is all glamour, right? Well, for those rock gods who don’t have roadies and “people,” traveling with a guitar is a serious pain.

First, the case is an awkward size, always fun when you’re balancing other luggage. And you have to check it, which means trusting your precious cargo to unseen hands that likely don’t value your axe as much as you do.

Entrepreneur Jonathan Spangler saw the potential for a new travel guitar – one compact enough to fit in a backpack for easy transportation (especially in an airplane), yet professional-level look, feel and sound. There are several travel guitars on the market, but they are still too long to fit in a carry-on bag, don’t look, feel or play like a normal guitar, and taking them out of “travel mode” often means messing with the strings and/or a serious retuning.


Delve worked with Spangler and his music-tech start-up, Ciari Travel Guitars, to clearly define the requirements. It had to:

  • Be lightweight (less than 7.5 pounds) and fit in a normal backpack
  • Look like a normal-sized guitar (3/4 body and full neck) and appear normal from the front
  • Have just one action to unlock and lock
  • Be easy to string or restring
  • Convey a premium guitar experience.

The solution? A neck that hinges in the middle so it folds exactly in half and backwards, keeping the strings under tension the whole time. This architecture required a complex over-center, spring-loaded mechanism to allow the strings to move as the neck folded and to lock the neck in place.


Initially, we addressed three major technical challenges:

  • Design a mechanism that fits in the space and provides an ergonomic user interface for locking and unlocking the guitar. We created a kinematic model of the proposed over-center mechanism to estimate the forces the user would encounter.
  • Determine how to correctly design and tolerance the hinges so the guitar played and sounded great. We created a CAD model of the ideal fret board profile that would provide the “action” required on the strings.
  • Balance friction and spring force to maintain tension on the strings during transformation while stressing the strings as little as possible to avoid kinking.

We worked with a luthier (guitar fabricator/instrument maker) to help us work on the details from spec, size, look and feel – everything related to the fine art of instrument making. We built test fixtures and ran life cycle testing of the mechanism and tuning checks to see how the strings would hold up to repeated folding and tuning.

The Ascender in action.

Let’s talk about how we can help move your business forward.

Contact us today →
Sketch of a phone
Delve has merged with Bresslergroup. Learn more →