Pringles F-Bomb Model Rocket

thingiverse

The F-Bomb rocket model is crafted from Pringles cans, 3D printed components, and an Estes E motor tube or approximately 4 inches of a BT-50 tube. I utilized a standard-sized Pringles can at the bottom and a snack-sized can above the coupler. This design accommodates Estes E motors (if you use an engine block in the motor tube, D motors if you use both an engine block and a spacer), or Aerotech 24mm motors (both 24/40 reloadables or the 70mm single-use variety). If you choose not to utilize the engine block within the motor tube, you could place both Aerotech or Cesseroni 24 mm reloadables inside. WARNING: I have no idea how much actual thrust and pressure this rocket can withstand. The 24mm Cesseroni reloads reach up to G117, and I would be quite surprised if this rocket could hold together under that stress. If you're brave or foolish enough to attempt it, please record the launch and post it; I'd love to see that. Also, consider launching from a safe location. Please refer to the enclosed diagram for information on how to attach the motor tube. Note that the part labeled "Bottom" features a 5mm recessed area on its threaded end, which is designed to accommodate Aerotech motor thrust rings. Ensure the motor tube sits flush with the edge of this recess and not the bottom of the part itself. To assemble the boat tail effectively, first perform a dry fit of all the pieces together. Then mark where the top of the motor mount rests on the motor tube. After that, disassemble everything and glue the motor tube into the motor mount while ensuring epoxy is applied to both the "fins" of the motor mount. Next, align the fins of the motor mount with those of the rocket. You may need to sand these fins down to prevent them from compressing the motor tube, making it difficult to fit a motor inside. Ensure that both the fins and where the top of the engine mount seats in the boat tail are sealed with epoxy. Once all this dries, attach the bottom piece. The bottom piece and the engine mount are designed to "sandwich" the boat tail in place. Before gluing the boat tail into the rocket, note there are holes at the top for mounting a shock cord. These holes are intentionally small so they can be sealed if not used. I employed kevlar string through these holes but a screw eye could also be inserted instead. If you use kevlar like I did, ensure it is placed before assembling the boat tail. The nose cone features an eye bolt for mounting a shock cord. Put the eye bolt through the bottom and then place a nut on the inside. Epoxy this nut to the inside of the nose cone. When balancing this rocket for stability, you can add weight to the inside tip of the nose cone, but by using an eye bolt, you can modify this weight later if needed by adding washers. I added one washer to the rocket before balancing so that I could remove a little weight if necessary in the future. The boat tail and coupler both feature launch lugs for a standard Estes launch rod. However, I'm uncertain about how well they will hold up to repeated launches; you might want to cut them off and glue on regular lugs instead. I have not flown this rocket yet, so I cannot provide information on its performance. It should fly smoothly with a D or E motor. EDIT: 9/28/2018 - Added Large Lug ("LL") versions of the coupler and fins that will fit an Estes maxi rod. This rocket is substantial enough to require the larger rod type. EDIT: 10/4/2018 - Added rings with large launch lugs. These aren't strictly necessary, but as I had already constructed mine with the small lugs and wanted to switch to large ones, I cut off the lugs and printed the rings to cover them. This also concealed the seam where the coupler was located. Additionally, I applied some decals that are 100% authentic...ly made up. FLIGHT REPORT: Flew this rocket on a D12-3 today. Very nice flight. Straight and true. Not super high, but then that's to be expected with a D motor. Maybe 200-300 feet. Nice deployment and recovery. The F-Bomb flew so well I didn't need to...well...drop the F-bomb! FLIGHT REPORT 7/5/2019: D12-5 this time, another great flight! Here is a (poor) video taken with my phone: https://www.youtube.com/watch?v=R_8hv6GV5v8