Der Great Red Max (BT-80 Der Red Max) Nosecone

prusaprinters

<p>I had planned to make a BT-80 based upscale of Der Red Max (a Der Great Red Max) since before the Mega Der Red Max came out, and the MDRM was something I wouldn’t have a field to fly it in, so I stuck to my plan.</p> <p>The biggest hang-up was getting a BT-80 upscaled nosecone, and from searching online I know others ran into this wall as well. So first I modeled the original nosecone, comparing it to my DRM (see <a href="https://www.thingiverse.com/thing:5443870">https://www.thingiverse.com/thing:5443870</a>) and now I’ve upscaled it to fit a BT-80 tube.</p> <p>At this scale it is too tall to print on most printers, so I broke it up into 3 pieces that screw together. One piece is the shoulder and the other two are the nosecone. I also noticed there was enough room on the inside to fit an electronics bay so I set that up. The sled is a blank so you can drill holes for zip ties or put screws in it or remix it to suit you needs. There is enough clearance in the center for a 9v battery if you want.</p> <p>The bay slides into the bottom section of the cone from below, and when the shoulder is screwed in it holds it firmly in place. If you plan to use the bay, don’t glue the shoulder on. It is up to you if you want to glue the top nosecone section to the bottom section or not. If you do, apply the glue sparingly to the threads in the top section, so as it screws tother the glue is squeezed up to the inside of the cone rather than down to the outside.</p> <p>If it feels too tight screwing on the shoulder, screw it on and off a few times and it will get better.</p> <p>The photos were taken with no post processing, so there is a visible seam in the nosecone. I had a negative horizontal expansion setting on the first layer and that likely is why. Easy enough to fill and sand before painting.</p> <p>The threaded hole at the bottom will accept an M8 bolt. You can use that to add weight temporarily if you like. If the sled is in place, only 15mm of the bolt will fit inside.</p> <p>My print of the finished cone weighs in at 4.1oz (116.2g) with the sled, 3.2oz (90.7) without.</p> <p>Print Settings</p> <p>I used a 0.4 nozzle, layer height of .12, and wall thickness to 0.36. Printing the shoulder and the top took about 6hrs each, 14hrs for the bottom of the cone.</p> <p>Do not use supports with the two nosecone parts, they are not needed but if you have supports on it will mess up the threads. You might want to use a raft as they are prone to warping early on. The shoulder shouldn’t need a raft, but it will need support around the overhang for the shock cord mount.</p> <p>Supports should be blocked around the threaded areas at the bottom and top of the shoulder.</p> Category: Hobby