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I need to drill a large series of 2 millimeter holes (several 100) in pieces of plastic that vary in thickness between 16 and 22 millimeter.
The plastic will be ABS, PVC and acryl (not sure if that is the correct English term, I mean the clear stuff they make aquarium walls from).
I've got several pieces of each material and I need to do it one-handed standing on a ladder. The pieces of plastic are mounted on a frame high up on a wall. (One hand for the ladder, the other for the cordless power-drill.)
Luckily for me neatness isn't important. The holes don't need to be at a very exact angle as long as they are more or less straight in and go all the way through.
Some raggedness of the holes, even a bit of melting at the edges due to the drill-bit getting warm is OK as the holes won't be visible from up close.
Splintering the plastic however is NOT OK and I only have one go at this. The pieces of plastic can not be easily replaced if they crack or splinter...

I intend to use a 2 mm drill for steel, set the power-drill for high-speed and apply little pressure when drilling. I think the acryl and the ABS would be a bit to hard/brittle for a wood-drill (For the PVC it would probably be OK).
Obviously I need to let the drill-bit cool a bit between holes and maybe drill each hole through in 2-3 phases, possibly having to clean plastic residue from the drill each time.
Am I on the right track with this or will I be making a big mistake somewhere?

EDIT in response to various comments.
The plastic pieces are mostly horizontal inserts of a (much larger) company logo mounted on the roof/wall of a company building. It can't be disassembled without breakage (lot's of glue and some pieces were molded in place and wrap around the frame).
The horizontal parts of the construct gather rain-water which leads to moss-growth (eye-sore) and which provide ideal nesting-places for pigeons and sea-gulls (bird-shit and the noise of the gulls).
Management contacted the artist who designed the whole thing and he came up with the brilliant idea of drilling the holes. About half of them to let water run of and the other half to insert 12-15 cm transparent (so they are invisible from the ground) plastic rods to deny the birds access.
The artist is a cousin of the CEO. The CEO is heavily impressed by him and basically orders us to follow the artists every whim.
Access to the panels with a ladder is pretty good. I'm not worried about dangerous working conditions. Scaffolding only works for the lower panels. The upper panels are mostly located in recesses that are wide enough to get a ladder in, but to narrow for a scaffold. (For the lower part I will use a cherry-picker. That is a lot easier than a scaffold and gives me the same access.)

  • You're hosed. This is going to be a long, painful job. No matter how hard you think removing and replacing the sheets will be, it'll be far easier and much less dangerous to drill on a proper workbenck (preferably with a CNC machine) than to try this while up on a ladder. And further, please explain what your intended goal is. You're probably going to be happier (assuming the panes really can't be removed) cutting most of each pane out, installing some sort of screening with a secondary frame, and calling it a day. – Carl Witthoft Feb 27 '17 at 17:04
  • Have you considered scaffolding? The way you describe this setup predisposes you to broken bits, which might or might not cause more trouble. – Aloysius Defenestrate Feb 27 '17 at 17:08
  • @CarlWitthoft I know it is going to be long and painful. I added some clarification to the question. – Tonny Feb 27 '17 at 19:48
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    In response to the useful "edit" section: well, then :-( . If this were software -related, it'd be an instant hit over at thedailywtf.com – Carl Witthoft Feb 27 '17 at 20:12
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    @CarlWitthoft If it hadn't been a wetware issue I would have posted this on the thedailytwtf in stead of here :-) – Tonny Feb 28 '17 at 10:31
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The scope of your project requires an equally large scope of preparation. Swap out the ladder for a scaffold system. Replace the hand drill with, at a minimum, a drill jig to keep alignment while you drill. Use drill bits designed for drilling plastic to prevent cracking. Your emphasis on avoiding splintering/cracking increases the importance of proper drill bits. Using such a small diameter drill bit also increases the chance of snapping a bit in the hole. With a combination of scaffolds, a drill jig and proper bits, you may be able to accomplish your goal.

representative image of drill guide

You suggest that the holes need not be perfectly straight, but a jig will enable you to drill in a safe manner to avoid snapping a bit.

A quote from a plastics web site:

Plexiglass, Lexan, Plastic Drill Bits These are the bits you need for drilling Plexiglass, Lexan polycarbonate, PETG, and other clear plastics. The special tip design carves through the plastic (not for use with wood or metal).

It takes a special drill bit to properly drill through Plexiglas, Lucite, Acrylite, or Perspex acrylic sheet. Ideal for Lexan, Tuffak or Makrolon polycarbonate sheet. Special 60 degree angle. Not recommended for wood or metal.

These are specially ground flukes with a 90° point for drilling holes in acrylic plastics including, Plexiglas®, Lucite® and Acrylite® materials. Metal drill bits will not work as they are made to bite into the metal as they are pushed into it. If they are used on acrylics they will chip and cause other damage to the plastic.

When drilling holes for screws, you must make the hole larger than the screw itself to allow for expansion and contraction of the material. If not you will cause stress cracks at the hole and they will spread! Always have a backer board behind the plastic sheet - most problems happen when you punch through the back side. The design of these bits helps prevent that!

Bits for cutting plastic have a shallower angle to the tip as well as less aggressive cutting edges. The one in the photo below shows it is nearly a scraping edge rather than a cutting edge:

representative image of plastic cutting drill bit

  • The backer board is crucial and needs to be firmly held against the workpiece. I would buy new bits for the job to be sure they're sharp, and in that case getting a special one would be worth it - though normal HSS bits are fine if you're gentle. – Chris H Feb 27 '17 at 19:46
  • I had no idea there are special drill-bits for various plastics. I will find out exactly which plastics are used and buy the proper stuff. Thankfully I have a decent budget for this. A drill jig like that would be useful although I'm certain a fair number of the holes would be located too close to other stuff that I couldn't maneuver it in place. But for the larger areas (where a snapped drill-bit would also be most visible) this is most certainly a very good idea. – Tonny Feb 27 '17 at 19:56
  • @ChrisH I was initially going with HSS and being very gentle about it. Figured that would be the safest approach. – Tonny Feb 27 '17 at 19:57
  • I've tried the gentle approach in the past. What I learned is that the wrong drill bit bites even harder when it's turning slowly! You really can't control the physics involved in a drill bit that is biting, pulling in faster than it can cut/clear the hole which wedges into the plastic, creating a crack in the worst possible manner! – fred_dot_u Feb 27 '17 at 22:53
  • @fred_dot_u That is very good to know. I will most certainly buy the proper bits then. – Tonny Feb 28 '17 at 10:32
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Cover the area you are drilling in painter's tape, it will help keep the plastic together while you drill.

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    I didn't down vote you, but painters tape will not prevent the bit from digging in and splitting the plastic. Tape may prevent the bit from skittering or dancing around the desired location. – fred_dot_u Feb 27 '17 at 22:54

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