Homebrew PCBs

On Mon, 14 Jun 2004 07:13:07 -0000, Dave Mucha <dave_mucha@...> 
wrote:

> --- In Homebrew_PCBs@yahoogroups.com, dg140@f... wrote:
>> For larger holes in plexi, drilling a pilot or starter hole works
> well;
>> speeds at about 500-600 RPM,; and the plexiglass bit with its
> appropriate
>> flutes and sharpness.
>>
>
> The key to drilling plastics is to drill with a flat bottom drill.
> the normal taper drill will remove a lot of plastic and as it exits,
> the area of contact suddenly gets much smaller and before you know
> it, the flutes will grab and push thry, often cracking the part.
>
> a flat bottom drill, like an end-mill will not suffer the same exit
> problems.
>
> Dave
>

i see... thanks, that's goin to be helpful.

st