BCN3D Sigma bowden tube shim

thingiverse

This is a straightforward solution to the persistent problem of the Sigma printer bowden tube creeping out of the hot-end. By modifying a previous designer's post, I minimized the amount of plastic and supports required, but this design came with its own set of issues - it suggested a weakening of the bowden tube and necessitated recalibration each time the tube was removed and replaced, which was simply too much work. Recently, I added a metal shim to replace the threaded fitting in the Thingy (http://www.thingiverse.com/thing:1658562), and this proved to be an excellent solution, but constructing it presented its own challenges, especially for those without access to metal working tools, quality drill bits, or high-speed rotary equipment. Now that I have a simple design, I see no reason why building it in PLA should be a problem. This Thingy is my attempt at addressing the issue and providing a hassle-free solution. Print Settings: Printer: BCN3D Sigma Rafts: Doesn't Matter Supports: No Resolution: 100 micron Infill: anything above 50 percent Notes: Use 0.100 for layer height, as the goal is to achieve a shim thickness of 0.9 mm. The OpenSCAD code is well-documented and allows for easy modifications if necessary. Post-Printing: No cleanup needed. Pop the part off the build plate and slide it under the gripper ring. Ensure that you push it to its maximum capacity, which will place the edge of the shim opposite the opening in the gripper ring. The side "fingers" tend to splay during insertion, so this will lift the ring enough for the fingers to get underneath. How I Designed This: OpenSCAD makes parametric design a breeze when good code practices are followed. In my case, I had it easy - the previous metal shim was marked with its thickness and measured easily, allowing me to calculate the width accurately. The hole I drilled was 8.5 mm in diameter, resulting in a perfect fit on the first try.