I won't go into great detail here, but here is a link to an Instructable that spells out what I did to create this enclosure: http://www.instructables.com/id/3D-Printer-Enclosure-1/
Feel free to contact me with any questions: I made a bunch of mistakes in the process of this project, and maybe I can help you avoid those mistakes too.
Here's a few tips for starters:
I tried to drill holes and use conventional fasteners, but I experienced a disheartening failure rate whenever I put drill bit to acrylic. Curiously, the hole saws worked flawlessly every time, so the few hole I needed were thus created. Everything else is joined with 3D Printed brackets and some heinous plastic-melting epoxy.
These are the tools and materials I used:
5 - Acrylic (plexiglass) sheets 18" X 24" X 1/8 inch - $10.00 ea Home Depot
Rare Earth magnets (for "latch") various sizes / qty - $4.00 Home Depot
2 Inch hole saw
1 inch hole saw
Devcon Home Plastic Bonder (glues ABS to Acrylic - there are others, but choose wisely for best results. Disclaimer: Ventilation, hold your breath, ventilations, ventillatttionnn. bennalay...)
Straight edge, like framing square
Masking tape for preliminary fitting / assembly
Gizmacci 1-5 and a knob
Additionally, you will want some screws to hold the whole thing down and maybe some way to keep your 3D printer from banging off the walls of the box - I recommend the Vertical Board Anchor by CodeCreations http://www.thingiverse.com/thing:39778 Once screwed down, your floppish plastic box (assuming you built it square) will assume a surprising coffee table-like rigidity.
18"W X 24"D X 18 1/8"H (all instructions assume 1/8" thick plexi)
Don't. See: break, separate, split up, fall apart, come apart, fail, go bad, give way, die, give out, conk out, divide, damage.
Again, don't. You will get better results if you repeatedly score the acrylic sheet with a sharp point along a straight edge (I used the tip of a reversed pocket knife blade, scratching, NOT cutting). For best results, score both sides. Clamp at score and sharply flex. I found it helpful to invest in an extra sheet of plexiglass for experimentation and practice.
Mix small batches of glue. Trying to get everything glued at once is a recipe for haste and waste and disgrace. Take your time, and glue no more than four things at a time. Did I mention VENTILATE your work space? You only get one brain.
These are brackets for gluing up a right proper and square box from acrylic sheets (AKA plexiglass).
These are extra brackets (should you need/want them) for gluing up a right proper and square box from acrylic sheets (AKA plexiglass).
This is an adjustable vent that sit atop the plexiglass enclosure to passively vent hot air and fumes through convection. This is designed to fit in 2 inch hole. I had very good success with a new hole saw at slow speed.
The pin the vent spins around is a section of 3.0 mm ABS filament that has the ends "peened" with a hot element, like a soldering iron. You can clean out the small hole with a 1/8" drill bit which is just a tiny bit bigger than 3.0mm.
These are hinges for the door to the enclosure. The pin the hinge hangs from is a section of 3.0 mm ABS filament that has the end "peened" with a hot element, like a soldering iron. You can clean out the hinge holes with a 1/8" drill bit which is just a tiny bit bigger than 3.0mm.
These are designed for 1/8 inch-thick plexi sheets. There are two outside hinge elements that sandwich the middle hinge on the door. Mate the bottom element and the middle element such that their smooth (bottom) sides kiss. Your hinginess will be much smoother. The design of the faces that engage the plexi should suggest the area of glue application.
This "tray" contains a swiveling pass-through and reinforcing rings for wiring/vent holes. All these parts are designed for a 1 inch hole. I had very good results with a new 1" hole saw at slow speed.
An annoying property of acrylic sheet is how edge defects from cutting or drilling can spawn heart-breaking cracks (ask me how I know this) I think reinforcing any hole through plexi is cheap insurance. The Pass-through will fit 1/4 inch sheet or 1/8 inch sheet (like I used) with a ring as a shim. The photos should demonstrate how the Swivel Pass-through works. Be careful not to accidentally glue your swivel ball in the rings - it should move freely and be loose.
Since the two pieces are the same material, bonding them is easy, Use your favorite ABS glue or plain ol' acetone should work. This shrunken head was derived from "Cleaned Skull" by ssd. I added little round eyeballs in the orbits. Zoinks!
NOTE: there is a similar project on Thingiverse: http://www.thingiverse.com/thing:22119 The author suggests using a hot glue gun to glue it together - great idea and much kinder to the central nervous system.