New Router Speed Control

[Gerry Grzadzinski]

On a PC 690, there's about a 3/16" gap between the top bearing and commutator.

First thing was to pull off the top bearing, and paint the shaft half black and half white.

The housing partially covers the shaft here, so a minute or two with a round file opens it up a bit.

The sensor as supplied fits snugly into a 3/16" ID tube, so I epoxied a brass tube into place, being careful that it doesn't contact the commutator.

You can see through the tube the half white half black shaft.

I used a small amount of silicone to secure the sensor in place. The plastic cap on the 690 has a small gap between it and the body, which allowed me to just fold the wire down and the cap holds it in place. I have it tied to the mount right after it comes out, so there's never any pulling on it.

I'm waiting on the parts for the speed controller, and a new chip with updated firmware for more linear control from Mach3.

Here's a video drilling holes at 5000 rpm.
http://www.youtube.com/watch?v=N6FXbOPEzBM

Controlling the speed of the router with Mach would be super sweet. do you know if you can bypass the speed control on the Hitachi M12VC and use this to control the speed?

Yes, someone's already done it using the VFD output from a G540. There's more info at the Zone.

[Gerry Grzadzinski]

I machined a case from 1-1/2" acrylic and mounted it to the side of the gantry.

Also added a block of aluminum for additional heatsinking, due to the sealed enclosure. Testing shows it using only about 40-50% power or less at the lower rpms, so it should stay cool.

For 3+HP routers, a small fan is recommended.

[Gerry Grzadzinski]

Here's some pics I found of the modified Hitachi.

Users have also modified a Colt, PC 7518 and a few others. I think someones working on a Bosch 1617? right now.