PDP 8 panels. Feedback

[Jon Elson]

On 10/27/2015 11:59 AM, Chuck Guzis wrote:
> On 10/27/2015 09:33 AM, Jon Elson wrote:
>
>> The ultimate way to drill holes in Plexi is with an end 
>> mill.  It can
>>  make a slight chipping when it punches through the back, 
>> so you
>> either need a backstop material or lighten up the feed a 
>> bit just
>> before it goes through.  (This of course requires a 
>> center-cutting
>> end mill, I prefer 4-flute for this.)
>
> Sure, but I'm assuming that the original poster doesn't 
> have a Bridgeport mill at his disposal.  But a drill press 
> is quite within the budget of most hobbyists.  I'd think 
> that if you already owned a vertical mill, you'd know how 
> to work with plastics.
>
You CAN use an end mill in a drill press if you are 
careful.  You get no self-centering, so the work must be 
**SECURELY** clamped, as the cutter may try to walk.  But, 
you'll get perfectly round, smooth holes.
Twist drills tend to wander and make triangular and slightly 
helical holes.

Obviously, you can only do this with small size end mills in 
a drill press.

Jon