Homebrew PCBs

Joe,
I forget where I saw it, but one rule of thumb is 1IPM per 1000rpm of 
the spindle. It seems to be a good starting place and of course might 
need tweaking depending on your exact setup.

In the bit calibration program, yes I do have some problems with 
trace width less than .005" and I have not yet tried it in FR4. By 
the way, if your interested in the bit calibration as developed by 
Poul-Henning Kamp, you can find the information here 
<http://phk.freebsd.dk/CncPcb/calibrate.html>

Art
Country Bubba



At 11:17 AM 12/13/2012, you wrote:
>Hello Art,
>
>Is there any algorithm to figure out the feed rate? I am using a mill feed
>of 6 inches per min at 10,000 rpm and it seems to be working well (in my
>amateurish opinion). I am not sure what to look for (burrs, etc) to ensure
>that it is actually working fine. Any thoughts, please?
>
>I will just order the different degree bits and try them on to figure out
>which is better.




>BTW, I read that the CEM boards have a problem with small traces. The
>traces supposedly cannot glue as well to CEM as to FR-4. Wondering if you
>encountered that issue.
>
>Thanks
>Joe
>
>
>
>On Thu, Dec 13, 2012 at 11:05 AM, Art Eckstein <
>art.eckstein@...> wrote: