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The company I used to work for made firealarm panels in much the same
way....the only difference is I might have had 100 or more holes to
drill in a single sheet.....Over 4 years and hundreds of panels, I only
cracked one (cause the holes were too close together)
Here's the tricks....
First....leave the paper coating on the plexi until after you are done
drilling. Some of the mfg use a thin plastic...take it off the side you
are drilling...it only gets in the way.
We used a drill press on a medium speed, the table of the press was
covered in particle board then that was covered by another plastic
(sintra) that we used...The sintra helped, but was not essential. The
thing you have to do first is drill a small pilot hole (1/16"~3/32")
then drill slowly but smoothly with the HSS or bradpoint. On holes over
1/2" we used a step bit. Be careful as when the drillbit breaks thru the
far side of the plexi, it will tend to chip a bit around the edges if
you are pushing too hard. Try it on a few pieces of scrap first to get
used to the cutting pressure..
Remember, let the bit do the cutting, do not force it. Second..dont
cook the bit as it will transfer the heat to the plexi and make it
brittle and consequently prone to break.
Kim Roland wrote:
I tried to do about that very thing a few years ago. I was unable to
drill the plexiglas without cracking it. I ruined a couple of pieces of
plexiglas before giving up and doing a plain masonite panel, painted
grey with the track schematic done in black tape with rub on lettering.
It was a disappointment since I had a really nice full color panel, with
lettering and everything done in a CAD package and printed with a color
inkjet. Since then I have heard you can drill plexiglas by using a
specially sharpened twist drill. You might want to ask the plexiglas
shop if they can do the special drill sharpen trick.
David J. Starr
<pre wrap="">Just a thought, why not make a nice printed panel then have it
Punch the required holes in it and then glue to the masonite etc. backing.
The easy way to drill plexiglass is to lay another piece of plexiglass
(scrap piece) under the piece you are drilling.Make sure they are on a
flat surface & the pressure of laying flat is equal on the 2 pieces.
You can use regular drill bits, just drill slow.There is no need for
special bits. I have built many projects useing plexiglass & the above
method is simple & you cant go wrong-just take your time. Kim