Automotive & Industrial

More spring rate from the package you already have

DYNEST casts a steel coil spring inside an elastomer part so that the spring confines the elastomer around it. Outside diameter, bore and height stay the same. In measured steel-polyurethane elements, the rate runs 2.6 to 3.3 times higher than a rule-of-mixtures estimate for the two materials.

Skateboards are where the technology was proven. We are looking to explore it wherever a load-bearing elastomer part is fighting a fixed envelope. No production parts exist in the fields below yet.

Automotive

Loads on suspension bushings, mounts and isolators keep rising, while the space around them rarely grows. The usual options each cost something. A harder urethane grade moves the entire curve, including the soft initial travel that sets ride comfort. A stiffer coil needs thicker wire, which raises solid height and consumes usable stroke.

DYNEST is in development for specialty and performance suspension bushings, mounts and isolators, where a part needs a higher or more progressive rate in the space it already has.

Other fields we want to explore

• Industrial equipment: vibration isolation and force-limiting components with load-dependent behavior

• Medical devices: compact, tunable force profiles where space is tight

• Aerospace hardware: weight-limited parts where more performance from the same volume matters

• Microelectronics: precise force delivery in a small footprint

• Bicycles: suspension and damping, where soft and stiff are traded against each other

How it works

Under compression, an elastomer sheds load by bulging outward. With a coil running the full height of the part, that bulge is largely blocked, so the material between and around the coils is forced to work. The steel itself carries only a few percent of the load directly. Most of the gain comes from confinement.

The result is a progressive curve: compliant at first contact, then climbing steeply as load builds.

Materials and manufacturing

Cast polyurethane is the matrix in production and the one characterized so far. The architecture extends to silicone-based and other elastomers across the durometer range.

A 2026 survey of public sources identified more than 100 US contract molders in 33 states as candidate manufacturing partners. They work in cast polyurethane, liquid silicone injection and press-molded bonded rubber, so a program can be matched to the process, volume and quality system it needs.

Development status

Established so far:

• Quasi-static force-displacement characterization across four matrix grades, with replicate runs

• Two architectures: a spring cast into a bushing, and elastomer cast into a spring

• Commercial production of DYNEST skateboard suspension bushings in 2026

Next:

• Rate-dependent compression characterization, with a plan in place

• Dynamic stiffness and damping across frequency and temperature

• Heat aging, fluid resistance and fatigue, defined jointly with a partner against the relevant specification

Working with DJLL

Development: paid and non-exclusive by default. We design, prototype and characterize a DYNEST element for your application under NDA. You own your application IP. DJLL retains DYNEST and improvements to it.

Exclusivity: available at the conclusion of a development program and priced separately, with narrow grants by category, territory and term, backed by performance minimums.

Manufacturing: DJLL writes the specification and qualifies partners to produce against it, verified by first-article characterization.

Send us a load, a displacement and an envelope. We will tell you whether a DYNEST element fits and what it would take to prove it. info@dynest.tech

What a DYNEST element looks like

The DYNEST HST element is polyurethane cast into a 6 mm music-wire coil spring, shown here in four matrix grades from Shore 50A to 80A. It is in production today as a skateboard truck spring, and it is our example of the elastomer-cast-into-a-spring architecture at a size closer to industrial hardware.