MadCow BOMARC Sanding and Assembly Tooling for 2.6in Rocket Kit

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I created two sanding guides to help me draw or sand the parabola shapes of the conduit ends of the MadCow 2.6in BOMARC precisely. Next, I designed an alignment guide to position the ramjet cones when applying epoxy, a crucial assembly step that requires attention to detail. To use the sanding guides effectively: The idea is to place these guides on either side of the conduit end, over the wing in this case, and then use them to mark the area for cutting or sanding. Alternatively, you can leave them in place as a visual guide while doing a rough-sand or cut. You may want to consider drilling holes in the straddle-bits to allow you to secure them with stick-pins. Alternatively, you can use painter's tape or masking tape to hold them in place while working on the project. Depending on how your conduit has been sanded already and any differences in clamping arrangements compared to mine, you may need to modify the straddle-bits on the STL or cut down the printed part to fit your needs perfectly. To use the alignment guide: Always perform a dry-fit before trying with adhesive to ensure proper size and alignment. Apply a small amount of epoxy or wood glue to the mounting surface of the small ramjet cone, then insert it into the hole of the positioning guide from the side with the 1mm depression. Carefully place the guide and small cone onto the large cone using the 1mm depression as a reference point. The depression should fit snugly over the front of the larger ramjet cone. Holding the small cone in place, carefully lift the alignment guide off the small cone. Clean any excess adhesive from the aligned parts (or wait until dry and sand). Remove excess adhesive from the alignment guide before working on the other cone. Uncured epoxy can be easily removed with a paper towel soaked in rubbing alcohol. Printing Details: I printed these guides in PLA using my Printerbot Simple 1401, which still works fine after upgrading with drive belts. I used 20% infill and no support material, printing at .5 nozzle, 40mm/sec, and a .2mm layer height. Each piece was printed independently. The long sanding guide took about an hour to print, while the short one took 40 minutes, and the ring around 30 minutes. The cone alignment tool was initially poorly sliced by Cura, requiring me to trim out a spurious top layer with an Xacto knife and then sand it smooth. It printed perfectly sized for my parts on the first try otherwise.