Router Bridgeport Spindle Adapter

I created this to clamp on the popular Dewalt DWP611 trim router to my CNC Bridgeport. I've always fantasized about having a high-speed spindle or machining an adapter from a large aluminum casting. The latter may still be in the queue but for now I decided to give 3D printing one a go.

I printed 50% infill (~500 grams) with PLA+ and am pretty happy with the results.  I put a dial indicator on a tool in the router collet to measure the initial system rigidity. With firm pressure in x and y directions I get less than +/- 0.002inch; and <0.001" in z-direction. The fasteners were designed for ¼" hardware and semi-captured nuts (but M6 would likely also work). The fasteners are accessible from the front and I use slightly smaller OD washers (~.47") to minimize local stress. The offset between spindles is meant to keep the two axis very close for rigidity but still allow for the router to clear the spindle housing. Overall, this gives a little more than 1" of total z travel with the router fully inserted.

So far I've tested some engraving on wood and aluminum and I couldn't be happier. Time will tell if the mist coolant I use will negatively impact the adapter strength/rigidity but this won't be a daily driver. A drawback I realized after a couple uses is that I cannot change out R8 tooling while the adapter is in place. This is because I cannot raise the spindle far enough to access the drawbar hex. I suppose this could be addressed to some degree by using an R8-ER adapter but I haven't tested that yet.