RESEARCH PYRAMAC
The initial concept came from my son who was doing a report on the Great Pyramids in Northern Egypt, specifically the Pyramids of Giza and modeled after Akhet Khufu's pyramid.
My first prototype of the Pyramac was going to be approximately a 1/400th scale of Knufu's. The sloping angle of the sides are 51 degrees and 51 minutes. Using this information I could not fit all the internal components inside the Prototype. I thought about mounting some of the components on the outside such as the power supply and hard drive on the back wall but decided that was to shabby looking, plus I wanted to use a UV effect illuminating the internal components from the inside. So I kept playing with different degrees and finally arrived at 60 degrees and zero minutes that allowed all internal components to fit nice and tight.
I also wanted the Pyramac case to be made of clear acrylic so inside of the case was easily visible with all the UV treated glowing components.
I was very new to working with acrylic. I had used a dremel on cutting plastic with previous mods with horrible results, ended up with melted plastic goop. So I had to do a little research on how to successfully cut and mold acrylic into specific shapes that would also be sturdy to support various computer components.
After doing some research I found that using a "RotoZip" or spiral saw works wonders cutting acrylic without melting or shattering the material.
THE CASE FOR PYRAMAC
Parts Lists
Some of the major supplies I used for the Pyramac mod.
1. (3) sheets of 1/4" 24x36 plexiglass from a local hardware shop, er, Home Depot - about $30 each. Also use 1/8-inch sheets which proved almost useless due to lack of strength and shattering/cracking.
2. (1) Ryobi Rotozip $40 on sale.
3. (5) Nickel plated 30-inch hinges.
3. Tons of various screws, nuts and bolts, and last but not least, one unsuspecting Graphite Mac 466 tower.
Some basic facts on Acrylic
This information is based on my personal but limited experience working with Acrylic for the first time on the Pyramac Project. I don't do this for a living or anything, just for sheer pleasure and hopefully not screwing things up too bad.
Acrylic characteristics
• Half the weight of glass
• Impact resistant, not drill resistant.
• Unaffected by sun or salt spray
• Temperature range of -30 to 160 degrees F
Cleaning
Wash with mild soap or detergent, with plenty of lukewarm water, dry with soft cloth. Oil or tar can be removed with hexane or kerosene. Solvent residue should be removed by washing immediately.
Do Not Use window cleaning sprays, scouring compounds, acetone, gasoline, benzene, carbon tetrachloride or lacquer thinner.
Masking
When working with the material, leave the paper masking (protective) film on the sheet as long as possible. Except for intricate detail work you should remove the masking only when your project is completed.
Working with acrylic sheets
DO
Keep masking on as long as possible.
Use metal cutting saw blades and drills which are ground for acrylic sheet.
Make sure all tools are sharp.
Wet the material before cleaning.
DON'T
Use saw blades with side-set teeth or Dremels which can turn Acrylic into a hot, messy, melted goop.
Cutting Acrylic Sheet
Cutting with a knife or scriber. Acrylic sheet up to 3/16" thick may be cut by a method similar to that used to cut glass.
Rotozip - ing
For cutting Acrylic or plexiglass if you prefer, I picked up a Ryobi Rotozip that worked wonders cutting Acrylic. Acrylic or Plexiglas is actually PMMA (Poly Methyl Meth Acrilate) and not to be confused with 'Liquid Metal" *laughter in the distance*
Finishing Acrylic
Sanding edges. You should sand raw cut edges for a couple of reasons. Sanding edges gives you a nice finish and freshly cut raw edges can be just as sharp as glass, cutting wires and more importantly, your fingers. Start with around course 120 grit sandpaper, used dry. Then switch up to a 220 grit paper, dry. Finish with a 400 grit wet/dry paper, used wet. Grits as fine as 600 may be used. Use a wooden or rubber sanding block for great finished edges.
Forming Acrylic
Acrylic can be heated to make it pliable. It will become rigid again when it cools. Never heat acrylic in a kitchen oven. Explosive fumes can accumulate inside the oven, and ignite. Boom!
I used a plumbers torch to heat and form the acrylic. Heat the Acrylic piece until it begins to sag and bend at the desired line/area. Sheet thicker than 3/16" should be heated on both sides for a proper bend. Use forming jigs or clamps for best results, and wear heavy gloves when handling heated acrylic. Forming other than straight line bends will generally require specialized equipment or molds.
Adhering Acrylic
For gluing edges, I found a brand that seems to work best. Weld-On 3 and/or Weld-On 4 cement. It's a high-strength, fast drying, clear, and water thin acrylic cement. Weld-On 4 is a little slower-setting solvent cement for bonding acrylics but still adheres pretty quickly. Although I tested these and they worked great I went the screw-hinge route for one basic reason, 1. I needed to be able to rip the thing apart and F. make necessary adjustments when needed.
More info on Acrylic adhesives can be found at:
http://www.tapplastics.com/
Disclaimers
The above information is based on limited personal experience and more often than not he really doesn't know what they are talking about. Please do and do not use this information at your own risk. Hey, if you had any sense you wouldn't be spending all your spare cash and time on absurd or fanatical mods, but then again, why not!?
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