Cutting Plastic and Plexiglass

[CompGeek01]

Hey guys,

I'm new to the field of modding. I've done years of building computers now I'm going to try actually "building". I have a few questions.

The first thing I've been wanting to do is the (what seems to be more commonplace now adays) NES computer. I've been cleaning out the case with my new Dremel and I just wanted to ask:

How fast should I cut with the Dremel so the plastic doesn't melt too much but it still cuts? I'm using the cutting disc that comes with the kit. So far I've been seeing that about 8k RPM works good (i've got a 5k to 35k adjustable Dremel)...or the 4th level setting. I think I just need a lot more practice.

After I get the case more or less "hollowed" out..I need to cut some thin plexiglass (?) to act as a makeshift mobo tray (maybe not needed, but I want one.)

How do you cut that stuff? Maybe 1/8" thick? The only stuff I've ever worked with is wood...all this plastic is beyond me for now.

[bubbalou32]

For straight line cuts, the easiest way with plexi is to score a line using a straightedge and crack it over the edge of a table.

[Happy Joe]

Most wordworking tools will work for plexi just watch the tooth count on sawblades (most wood blades are too coarse). Use extra masking to protect the plexi from scratches and use a lot of support to keep large pieces from floping and cracking. Use twist bits for drilling.
When you peel the plexi do it far away from any electronics as you can blow the electronics from the ESD (electrostatic discharge). I am always paranoid about plasticsheet next to electronics for the same reason.
Enjoy!

[Johnny Fist]

As far as cutting the NES case goes, I'd use a carbide bur for your dremel running somewhere in the middle as far as speed goes. Those cutoff wheels are meant more for cutting hard steel as opposed to cutting plastic. You can actually run the dremel at full RPMs with a bur as long as you work fast with it so as to avoid that annoying plastic melting fiasco. When I said fast, I meant fast, too. Probably faster than you're going to want to work. So if it doesn't work out for you, slow down the RPMs and work slower. Plastic really isn't all that much different from wood once you get the hang of it.

[leprechaun_40]

Having worked extensively with Plexiglass I hope I can offer a bit of good advice.

Treat it like HARDWOOD. Use a fine toothed saw for cutting, a very sharp bit for drilling and you can file or sand the edges with a fine grit paper. I've tried the scoring method and although it works, it's sometimes unreliable and will not give you the desired results. Do be careful when cutting or drilling. If you move too fast, it'll melt.
Also, what was said about masking is a great idea, prevents unsightly scratches in the finished work.:t