Re: Routers

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Gregory Kamysz
<smsupply@a...> wrote:

> How many of you are using routers for cutting metal? Can you get

enough

> accuracy from a router? <snip>

Accuracy is an elusive concept in CNC. It is a combination of a lot
of things. There are certain things you can say: One is that your
accuracy can never be greater than the sum of your inaccuracies and
that one inaccurate component will spoil the total system accuracy.

Will a router be more accurate than a roto zip? theoreticaly it
should, since it has larger bearings and should have better run-out.
Now we have to ask if the rest of the machine has the ridigity to
handle the larger router/weight and the added forces.

Several of the list members have been using routers to machine
aluminum. Like all material there is an optimum feed and speed for a
given cutter size and geometry. The needed RPM will diminish with
the metal and as you point out the speed control is essential. One
byproduct of pure voltage speed control is that reduced voltage also
brings reduced power and torque, often when you need it most.

Chip removal in cutting metal is more important especially if finish
is important. Most metal cutting operations are done using a coolant
of some form (mostly mist or flood) to not only cool the cutting tool
but to lubricate and help remove the chips. At the very least a
stream of compressed air blown to help remove chips is needed.
Aluminum cut at the wrong speed tends to "gum" and that can make for
some ugly cuts.

Even in routing woods of different types, users have found a vast
difference just by changing the router bit geometry. A 2 flute
spiral cut bit with uplift works better on dense woods or manmade
composites that have glue type binders. I had my worst experiences
when cutting relatively soft wood like pine and then hitting a patch
of sticky sapwood...instant bit snap.

If you want to use 1/8" shank bits with 1/4" router collets you can
pickup some Adapter Bushings from MLCS (www.mlcswoodworking.com) for
4.00 each.

So tell us a little bit about your machine and how it is built and
the accuracy answer can be a little more accurate....did I say that?

Tom C