Since the McLaren spygate episode of 2007 I have had a lingering interest in the J-Damper, jounce damper, or inerter. Whatever you want to call it, the device shaped the political and cultural landscape of F1. Since 2007 more information has dribbled out regarding the device, but only occasional posts or pictures and videos surface. Most recently an interview was posted on YouTube with the inventor Malcom Smith and they speak at length regarding the design and use of the inerter or J-Damper. Spygate of course was a massive point of contention for Formula One during that era, but in the vacuum of the outlawed tuned mass damper, the interter subsequently was adopted by many teams. Especially once its use was understood. In 2022 it was made illegal by the sporting body and as a result the jounce damper has been relegated to history, at least for now.

Part of my goal with this project was to create an interesting and fun model that was functional and unique. I used an off the shelf ballscrew and nut, nothing exotic, then designed around these parts to produce a simple free standing desktop j-damper.

It has resulted in a simple yet elegant design, at least from my perspective, but what wasn’t expected was how much fun it really is. It’s like an adult fidget spinner or a stress ball for F1 and suspension nerds. Not only is it fun to pull and push, watching the motion of the flywheel as it spins and resists motion, it’s also fun to tear it apart. The large custom threads I machined into the body section make for quick assembly. I opened a window in the side of the body as to allow a clean view of the ballscrew when it’s fully inserted inside the inerter body. The bump stops on both ends are custom designed to prevent damage and contain the screw at the ends of travel. On the attached end of the inerter body, it is fixed via a heavy duty spherical bearing just as it would on the real item, this accounts for misalignment and allows for movement of the damper on the stand. The magnetically attached flywheel is a breeze to clip on and off after removing the handle. With the fly wheel mounted, it requires notably more force to move than without. Overall, it is a flashy desktop model of the J-Damper that adds a nice bit of style to my design office.

If you have questions about the J-Damper feel free to reach out to me via the contact page.