Rocket Enthusiast Uses 3D Printing to Make Precision Fin Jig for Body Tubes.
Lehr Labs leveraged 3D printing to prototype a low-cost dual side fin jig for cutting body tubes.
Matt Ward, a veteran of rocketry, knew too well the challenges of assembling a rocket. He is seasoned to the required meticulous planning, design, and construction. One of the core features of a rocket are the rocket fins. They are integral to the direction stability during flight. If they are not mated to the body tube precisely, It could mean game over for a pretty expensive rocket. Proper fin alignment starts with cutting the fin slots in the body tube.
Unfortunately, the unstable cylindrical geometry can make this process difficult and dangerous. Also, the body tube can be easily damaged if the cut isn't guided straight, or if too much pressure is applied to the body tube. "These kits can be very expensive, one bad cut, and you could be out a lot of money." Matt wanted a robust fixture to control these elements. He went to investigate ways for bracing the round body tube. After finding sub par options online. He decided to partner with Lehr Labs to develop a product to solve this problem.
He consulted with Evan at Lehr Labs to explore the design feasibility, manufacturability, and economics. Evan, who has a background in mechanical engineering, analyzed the design requirements, provided feedback, proposed improvements, and started drafting. After the design was finalized, the end fixture was printed out of one of Lehr Lab’s polyester materials. Separate fixtures were constructed for each size of body tube. However, as requested, each fixture accommodated for the slightly different tolerances from different brands' quality controls. The final print met the tight tolerances required to allow for the absolute no play requirement when cutting the body tube in the fixture. Lehr Labs has extensively tuned their 3D printers to offer top notch accuracy. Lehr Labs then finished assembling the final fixture which included hardware and steel plates fastened to the polymer PETG fixture. Matt was very impressed with the final product, and it provided him inspiration for additional projects in the future.
"Lehr Labs makes a quality product. I have a series of one-off projects for model rocketry. Lehr Labs not only 3D printed the unique fins, nose cones, and jigs, but evaluated and improved the design and engineering of each project." - Matthew Ward