On Thursday, September 12, 2013 7:04:18 AM UTC-7, Leon wrote:
On 9/12/2013 7:32 AM, Michael wrote:

What kind of material do you prefer?

Solid Pnenolic

(Phenolic plastic, like linen-reinforced Micarta, is a pretty good rigid choice).
You can duplicate a base plate pretty easily, by chucking a dowel in your router, and
using a solid-carbide router bit in a second router, with the same diameter as
the dowel.

The trick is, to mount the base-plate material, form a center hole by plunge-cutting, then
making a pin-router jig of router #1 with a dowel and the holed but uncut baseplate,
and cut it with router #2 which has a fully-formed base plate.

You can put a collar on the dowel to guide an oversize circle cut, making a large
circular baseplate.

I've done this with phenolic (to make a matching-diameter baseplate for a small router),
but it should work with aluminum as well.