Re: cheap HF trim router vs Dremel

Hi,
I've also have been using my CNC to machine PCB boards. It's been quite
the learning process.

Initially, I've was using a Dremel. Lasted about a month, with the motor
eventually burning out after about 3hours of more or less straight machining.

I then picked up a Makita trim router (model 37000, 7.2V cordless) at my
local tool store, for $39 cdn. (about $26 US) It came without the
battery, so I cut off the battery holder and hooked up an 9VDC 3amp power
source to it. It runs pretty hot, so I drilled a series of holes into the
plastic casing. The motor seems to run just "warm" now. Its been about a
year now, with no problems.

The real trick is to get the right type of bits and run them at a high RPM.
Regular carbide endmills (I tried ones down to 1/16" dia.) will wear out
before the board is finished. The electronics industries uses some
specilized carbide bits, both as drills and mills. You can usually find
these at surplus stores, recognizable by the little colourful plastic disk
that they have on their shafts. They work very well.

hope this helps,
Vincent.