High Speed Spindle (Router) Mount for a CNC Mill

I find myself doing CNC work on wood about half of the time so I thought it would be nice to have a high speed spindle.  I decided to mount my existing router to my CNC milling machine.  This is the same router I had previously mounted to my Poor Man’s Milling Machine before I bought the CNC machine (a Grizzly G0463 with the CNCfusion conversion kit).  After doing a little bit of Internet research I settled in on attaching a mount to the quill of my CNC machine.  The best source I found of similar mounts is found on this CNC Cookbook page: High Speed Secondary Spindle.

First I started by casting the rough shape in aluminum.  Below is a picture of the wood pattern that I made and the aluminum part in the as cast condition (after the casting sprue and riser were removed).

After I had the cast part I bored out the two holes to closely fit the quill on the mill and the outer diameter of the router motor I planned to use.  Then I cut slots in the ends and a clearance scallop for the existing gear rack on one side of the router body.  Next I added fastener holes that are clearance fit on one side of the slot and threaded on the other side of the slot.  Fasteners tighten the mount onto the quill and router body to hold them securely.

Finally the router motor is installed in the mount and the mount is installed on the milling machine quill.  This configuration added a lot of mass to the head stock so I also added a gas spring (not shown) to compensate for the added mass.

With the addition of the router motor I am able to cut wood at a much faster rate and get a better finish.  Below is a picture of a couple of plaques that I made for my brother with the new high speed spindle.  (The picture was taken before the edges of the plaques were finished).

The plaques were made to commemorate PHD Baseball’s Worlds Longest Baseball Game that took place in August 2014.