Clear Holes in Acrylic?

Hey all,





I have just drilled holes in the sides of my acrylic for the leds in my ftir touch screen attempt, but the insides of the holes are pretty opaque, and don't transmit much light. How can I make the acrylic clear inside those holes? I've tried adhesive sandpaper around a dowel, spinning in the drill, like a getto dremel, to no avail. Ideas?





Thanks!





--Legs





P.S. not strictly engineering, I realize, but this is the closest category I could find...Clear Holes in Acrylic?
Polishing is a process of using progressively finer grits. First start with something a little coarse (100 or 200 grit) and then halve the grit at each step (200 -%26gt; 400 -%26gt; 800 -%26gt; 1600). Above 800 or 1600 grit, you will be using a polishing paste, not a paper. To use the paste, you apply it directly to the tool, or to a fine cloth.





The holes are probably small, so bending paper around a stick probably won't work too well. You may just have to start with the coarsest paste you can find.





Since these are holes, you may end up burnishing them with a brass or glass rod. Burnishing is different from polishing, in that it uses pressure to smooth down minor rough spots. But the surface needs to be almost smooth to start with.





Another thing you might try are these CD/glasses repair kits. A few of them are acrylic resin, but most are actually a liquid wax with a refractive index close to acrylic. They usually make a very smooth surface. Many of these kits are 2-step. The first being a medium polishing compound, and the second being the wax.





Edit--





Using acetone to polish acrylic is called ';solvent polishing';. There is also a polishing method that uses heat called ';heat polishing';. Both of these polishing methods impair the structural stability of acrylic and can lead to crazing, which is the fracturing of the acrylic starting near the polished point or edge.





Also, what they didn't tell you in ';How It's Made'; is that the acetone bath is actually a saturated solution of polymethylacrylate in acetone. It doesn't polish the handle, as much as it leaves behind a smooth film of new acrylic when it dries. Then again, I guess they could have been straight up solvent polishing the handles. I have certainly used cheap acrylic screwdrivers that started fracturing for no apparent reason.Clear Holes in Acrylic?
Acetone on a q-tip will melt the whiteness from the hole leaving it water clear and shiny. This will be a lot easier than trying to polish the hole until it is shiny. I saw this done on the show How it's Made. Screwdriver handles made of acrylic were being dipped in acetone to restore the clearness and gloss after a turning process made the outer surface white.





Edit: Wow, someones insecure about their answer! If you want the ten points so bad, fine, you can have them. All I ask Legs is that you try my suggestion on a scrap and see what you think before you waste a bunch of time and money.