Bowden extruder caliper mount

thingiverse

Most people suggest using a pen to mark their filament when setting up DEFAULT_AXIS_STEPS_PER_UNIT on their extruder, but that method leaves room for error. The included STL is tailored specifically for Think3DPrint3D extruders, and I've added a fully customizable OpenSCAD file so everyone can have fun with it. Instructions Simply attach this device to your bowden extruder, and you'll be able to precision-tune your DEFAULT_AXIS_STEPS_PER_UNIT in no time. The included STL is accurately sized for the Think3DPrint3D extruder, and I've included a customizable OpenSCAD file so everyone can use it. To use, position the calipers in the slot, making sure the screw plate rests in the lower slot to prevent them from slipping back. I strongly recommend holding everything firmly in place while you do this - during testing, I had a shoe box under my calipers to keep things steady. Next, extend the caliper to the filament hole, and then extrude 1mm at a time until the filament starts pushing the calipers closed. Zero the caliper immediately, then extrude 10-20mm while keeping an eye on your calipers - as they close under the pressure of the extruding filament, you'll see the reading shift. Note that number (it will be negative) and make the necessary adjustments to your DEFAULT_AXIS_STEPS_PER_UNIT. It's a good idea to gently push the filament into the groove before taking your final measurement, as it can sometimes bend upwards - but once you have your reading, you'll be ready to print like a pro!