In the last few years, when considering what to make for a halloween costume, I've begun with characters which have had a strong, positive effect on popular culture. strong, popular characters which aren't really human. I have a really good idea for Halloween 2009, simple in concept with just a couple of engineering challenges. The first thing I did was to have Stacy take a photograph of me standing up. Lately I've started my design with a photo composite of myself behind an image of the character I'm transforming into. Concept photo composites from Previous years: California Fandango Paper Bag American Idol Judges Dwight Shrute Bobblehead Sees Candy The primary challenge this year was where to hide my face. Generally, the first thing people look at is your face, so if you want them to look at your costume, particularly if your costume already has a face, you've usually got to obscure your own face. This costume would need to sit high on my shoulders. Lately I've abandoned the backpack frame in favor of just bending some PVC pipe with a heat gun. PVC pipes are about a dollar each, and I can usually avoid buying connectors by bending up the shapes I need. Straight Bent shoulder yolk I suggest bending PVC outside, because there is some fume and fire danger. You could probably use a hair dryer if you don't have a heat gun. You could probably use a space heater. I used to use a charcoal barbeque, so don't think you need the ideal equipment to pull this off. To bend PVC: Bending PVC is really easy. Don't let the length and complexity of these instructions concern you, I'm just trying to deliver as much information as possible. Basically you just heat up a section of pipe until it gets soft, then you bend it. Don't start with an entire 10 foot pipe unless you have to. A long pipe is unwieldy, especially once it has a couple of bends in it and starts knocking things off of shelves as you rotate it. Try to predict how long the finished project needs to be and cut the pipe first. Mark where I would like the bend to start and end. tight bends (smaller than 3" radius) are really tough, but these gentle ones are pretty easy. prepare a wet paper towel or rag. Use the gun's highest setting to heat the area you would like to bend. Keep the gun moving, heating up a short area of the pipe (8 inches) for a tight bend or wider area (16 inches) for a gentle bend. Rotate the pipe in your hands so that the pipe gets hot all the way around. The heat doesn't travel far down the pipe, so I usually do this part with bare hands. After a minute of heating, try shaking the pipe to see if it is starting to sag. I usually heat it up a little more after it starts to sag. That seems to help make a nice clean bend without kinks. When the pipe looks weak enough to be bent to your will, turn off and set down the gun and pick up the wet paper towel. Bend the pipe, being wary of crimping the hose. You can use the wet paper towel to protect your hand and cool the pipe after it is bent. Often I will try to counter kinking by squeezing the sides of a collapsing pipe, forcing it back to a round cross-section. It is Ok if it isn't perfect, you know, unless it has to be perfect. I stole one tip from GK Bayne, she recommends bending pipe around a paint can or bucket for a smooth curve. Wipe the pipe with the wet paper towel to cool it down until it hardens, about a minute. There is usually some steam involved. The wet paper towel will transfer heat to your skin much quicker than a dry one, so be wary. It might help to have a bucket of cold water nearby in case your rag gets too warm. You could probably quench the whole pipe into cold water, but I don't know what that would do to the structural integrity of the plastic. Probably nothing. A few people have suggested that I try filling the pvc with sand before I bend it, but I'm pretty comfortable with my method, so I haven't tried that yet. Usually I try to make compound bends in separate steps, heating, bending and cooling, then re- heating, re-bending and cooling. Never even once has my pvc pipe become too hot and melted into a globby puddle. I was engineering this as I went. I needed a long rectangle sitting on my shoulders like a table. The pipe for the shoulder harness required the most complicated shape. Next I added a support bracket for the front and a giant rectangle surrounding the whole thing with the final size I needed. Finally I added a rear support bar and screwed the whole thing together. Walking around with this lightweight, well-balance rig, the potential struck me. I could build up a massive structure on top of this. I could drop a skirt around it, anything. Unfortunately, the main rectangle needed to be a bit higher, just below my eyes, so I re-bent the rear bracket and moved the screws on the front. I also added a little foam padding to the shoulder yoke. Success! Next I started building two low boxes for the main structure of the costume. Luckily I had sequestered two giant John McCain for President corrugated plastic signs last year. Corrugated plastic is perfect for costume construction because it is very flat, light and strong. It would probably cost a fortune if I ever tried to buy it, but there is usually an ample supply poking out of vacant lots advertising Real Estate Investor Seeks Apprentice, or We buy Houses for CASH. I think it might even be lighter than cardboard. I marked out the final shape with sharpie and cut it with a utility knife. I wanted a box, so in some places I just cut halfway through and bent the sheet into corners. I used hot glue to cement the pieces together. The construction was pretty sloppy in places, but all of this will be covered in paper mache, so it didn't have to be attractive. Besides building, I also kept an eye out for parts. I needed two clear domes, each 15" in diameter. They were probably going to end up being $40 each, but I had lots of time so I checked every other resource before I actually bought anything. I looked at bowls at Target and the 99 cent store, light fixtures at Home Depot, security camera housings on ebay, round skylight lenses at the round skylight store, and serving trays at the restaurant supply. I preferred plastic, but it quickly started looking like glass was going to be the cheapest way to go. I had a backup plan. Recently while researching sculpting and mold-making techniques, I came across a pretty good tutorial on vacuum forming. Vacuum forming is used to suck hot plastic sheets down onto a shape, so that a thin clear plastic mold is created. I didn't want to have to build a whole vacuum chamber, and I definitely didn't want to sacrifice our home oven to experimentation (RIP clothes dryer), but I thought this method would at least be worth exploring. I made a visit to TAP plastics on Auburn Blvd. and found their thinnest acrylic sheet. Two 16" squares cost about $6 each and I was on my way to becoming master of my own domeing. "I'll be back on Monday after I ruin these", I quipped as I turned to exit. "Oh, here, practice on these", the guy at the counter offered, handing over three rectangles of scrap. Awesome! Maybe I could pull this off! My plan was to heat up the sheets with a heat gun and have them melt into a bowl shape. I grabbed a steel colandar and dropped the first sheet of plastic inside. I cranked up the heat gun and fired away. Nothing happened. I guess I've gotten used to PVC plastic melting in one minute. This took much longer, perhaps 5 minutes passed before the sheet started to droop into the bowl, folding like a won ton wrapper. This was obviously not going to work. The plastic was bending, but not really stretching. I needed it to stretch into the bowl and stay tight against the surface of the bowl in a nice clean curve. On my next try, I took a page from the vacuum forming tutorial: I made a jig. I cut identical holes into two pieces of lumber and sandwiched a plastic sheet between them. I figured the only place the plastic could go was down, drooping into a nice smooth bubble. I came back with the heat gun and it worked! I could make a little dome! Even under the gun for 10 minutes, the plastic never got very pliant. I had to physically push down on the center of the plastic to get it stretched. When it cooled I removed the wooden frame and pulled it out. It looked great! Maybe not as convex as I needed, but definitely a good step towards my ultimate goal. Next, I needed a gigantic $5 bill, 65" wide and 27" tall. I could tell you that I felt anxious about scanning U.S. currency, but you all know I just took a photograph instead. For some magical reason that didn't seem like it could be illegal. After a failed attempt at using rasterbator, I scaled it up in photoshop, prepared to print it across 16 sheets and glue them together like a poster. Actually, Fireworks has a feature to automatically print across pages to form a poster, so I used that instead. This was going to look incredible, It looked as if I was going to need a new print cartridge however...