Howdy.
Alright... it's time. Back in the swing of things and such... from here on out, I have no excuses. Ninety-five percent of every single thing that I need to buy has been bought. The plastic people still have 3 or 4 other pieces to cut for me, but they are some of the 'last' pieces needed. Sooo... your 'hurry up, slacker' comments are now justified =p.
First, I said I'd talk about the bender a while ago. It's an incredibly useful tool and can be made for 1/10th the cost of a professional plexi-bender. I bought something called a "wire strip heater" from Tap plastics, although I've since found some local vendors that sell it for much cheaper. Anyway... this is the heating element that I use to bend the plastic.
Next, I bought a large piece of plywood from Home Depot. The idea is... you have a 3/4" to 1" wide channel to place the stripper into. You can do this with a router (which I don't own) or... the way I chose. The bender will be 24" long, so... I bought a piece of plywood that was 24"x24". I then had the sales guy cut the wood in half so I had two sections, 12x24" each. Then, I had the guy cut one of the pieces in half, leaving me with two 6x24" strips. Finally, I had him shave 1" off one of the 6" pieces, leaving me with my final assembly...
1 5x24" strip
1 6x24" strip
1 12x24" strip.
The 12" wide piece was the base for the bender. The two smaller pieces are then screwed onto the base, with a 1" space between them. If you go with heat resistant plywood, you don't need to insulate this... if not, it is reccomended that you place a layer of fibreglass in between the base and the two strips.
Next, a whole bunch of aluminum foil is bent around until I had a long U shaped channel... this is used both for heat insulation as well as reflection... a good portion of the heating depends on the aluminum foil. On one end, a grounding cable needs to be attached by a screw to the aluminum. The other end of this grounding cable should go to common ground.
Here we are.
Finally... when you have the aluminum foil channel secured in the path (using small tacks), you can place the wire-strip heating element inside the aluminum. When that's done... cong. You know have God-like powers over plexiglass. Little scrap pieces of acrylic bow down to your every whim. In fact, you might say... they'd bend over backwards HAHAHAHA!!! Villagers in Lexan-burg will sacrifice goats and cattle to appease you. You are PLEXI-MASTER. (too early in the morning... too much caffeine...)
Quick example of how easy it is to bend with this thing...
Step one: Heat it up for a few minutes, depending on the thickness and type of plastic. 1/4" lexan takes a bit longer than 1/8" acrylic.
Next... you can bend by hand, or use a wooden 'jig' to get your precise angles. I use a 90°/45°/45° carpenter's triangle and a long flat strip of wood. In this example, it's all by hand. You should take note that the only part of the plastic that heats up is at the bend... so... don't touch it with your hands. This is not only bad because of potential burns, but the fingerprints (and possibly flesh) will be permanently 'stuck' on the plastic. That sucks.
Now you can see how malleable the plastic has become. I've never had a fear of bending too quickly or pulling it apart like silly-putty... but it really DOES have the bend consistancy of... say... salt-water taffy. If you hold one end and flap at the joint, it WILL fly around. This gives you an idea on how easy it is to bend it precisely.
Once this piece is off the heat, it will start to dry and harden within 10-20 seconds. Plenty of time to get a precise angle. This time shortens if you are flapping it around the room shouting CAW! CAW! CAW! This took me several expensive pieces of plexi to figure out... it's either the airflow of the flappage, or there is some mystical connection between 'caw' and plexi-hardening time. Aaaanyway...
There you go. A perfectly rounded bend, with great optical clarity. Shine an LED into one end and the light follows to the other. Imagine the possibilities! And, yes... if you were wondering, that IS Stalin and Roosevelt sitting on their commodes.
So... I finished that plexi bender months ago... what is my excuse for so long in delaying the project? Well... a huge part were health problems. Headaches and then a few grand at the dentist (Damn you mountain dew!!!) prevented me from putting 'too high' a priority on this. But... that's all in the past! The project and I have renewed our vows of love and progress shall commence.