Dragknife & Pen Adapter for Bosch Colt Router Mounts

thingiverse

Properly swapping the tool mounts on an MPCNC Primo cnc router is a lengthy chore. So I designed this thing to make it easier to swap between a Bosch Colt router and a Roland style dragknife. This thing just slides into the Primo 1hp Colt mount I designed, which can be found here: https://www.thingiverse.com/thing:4632040 Since the adapter cup is the same size and shape as a Colt router, it will likely work with other mount designs as well. I have to give a shout out to V1; the parallel arm design I used was inspired by his original dragknife mount for the Primo. **BOM:** 1@ cnc router w/ a Bosch Colt 1hp router mount 1@ printed dragknife mount part (long preferred) 1@ printed Colt adapter cup part 4@ M3 nuts 4@ M3-10 bolts 1@ Pen or Roland style dragknife (like this: https://www.amazon.com/YF-Tungsten-Lettering-Cutting-Plotter/dp/B07P8DMC2J/ref=sr_1_1?dchild=1&keywords=drag+knife&qid=1611451549&sr=8-1) 3@ small zipties **Printing:** No supports are required for any of the parts. I printed in ABS, which gave good results. You can print in PLA or other filaments for more stiffness (if you have used V1's holder, it has the same flexibility). If more flex is desired than you can get with ABS (TPU is too flexible), you can simply trim down the width of the suspension arms with a razor to suit your needs. There are 2 versions for the dragknife part, long or short. The short version places the cutting point centered where the router bit would be, however it is quite a bit stiffer than the long version which generally makes it harder to use. The long version offsets the cutter toward the outside of the lower ring on a Colt mount. When using the long version, rotate the cup so the cutter is oriented closest to the z axis to reduce errors. **Assembly:** Use 3 or 4 small zipties to secure your roland dragknife cutter on the dragknife mount part. Press the four M3 nuts into the dragknife mount. Hold the dragknife mount in place at the correct height inside the adapter cup. Fasten the parts together with the four M3 bolts. Slide adapter cup down into your Bosch Colt router mount. Tighten the mount around the cup, and enjoy.