Welcome to DIY Haunts, Dispatch #3
Welcome to newsletter #3 of our DIY Haunts Halloween contest, sponsored by our friends at Jameco Electronics.
Your challenge is to build the creepiest animatronic prop possible, using sound, motion, and light. You can either design your own masterpiece or follow along as we build the Spooky Fun Tombstone Project, a scary styrofoam tombstone that splits in half while lighting up and playing creepy sound effects! In this issue of the newsletter, we'll discuss the process of shaping and carving your tombstone using a nichrome foam cutter. For more information and resources on the contest, as well as the official rules, refer to the DIY Haunts Landing Page.
—John Baichtal and Gareth Branwyn
back to top Sample Project: Flying Crank Ghost
While the official project of DIY Haunts is an animatronic tombstone, you can make whatever you want, as long as it moves, makes noise, and lights up. Check out Edwin Wise's excellent and very spooky flying ghost that we found on Make: Projects
. It's a great prop that uses a motor, pulleys, and cheesecloth to make a terrifying ghost decoration. Originally designed by Doug Ferguson of Phantasmechanics, he made the design public domain in 1997. Just remember, if you were to make something like this, be sure to include audio as well as motion and lights or our sinister judges will cackle as they dock you points.
back to top Cutting Styrofoam
The tombstone project calls for you to carve a tombstone out of styrofoam. The best tool for cutting foam is a nichrome foam cutter. Nichrome (nickel-chromium resistance wire) is a wire that heats up when electricity passes through it. Cutting foam with a saw is a great way to get foam crud everywhere and have a rough edge on your creation. Nichrome cuts neatly (limited only by how shaky your hands are!) and leaves little mess beyond the parts you just cut off.
You can buy a commercial foam cutter from most hobby and craft stores, but we used one made from scrounged parts, hacked together by the members of the Hack Factory hackerspace in Minneapolis for a previous foam project.
It's simply a wooden framework with threaded rods holding it rigid, and a length of 20-gauge nichrome stretched across it. The wire gets power from a spliced portion of an old extension cord plugged into a garage-sale model train transformer. We had to buy an 80-foot length of nichrome for it, and used less than 2 feet of that -- but now we have lots of extra for future projects! The total expenditure came to less than $20.
If you want to make your own, this Instructable shows you how.
back to top Shaping the Tombstone
First, find some appropriately-sized styrofoam. We found some at a hobby store for about $7 a sheet. But how often is styrofoam thrown out? You should be able to scrounge some waste foam if you plan ahead.
Next, you'll want to carve a design on the foam. If you check out Cory Derenberger's Styrofoam Tombstones project from Make: Projects, he does a great job of explaining this process.
For our tombstone, we went with a simple design, tracing a spindle of wire with a Sharpie to create the top curve. However, just as there are countless different tombstone shapes, you can make yours look any way you want. Just keep in mind where you plan to place the split. We decided to put it along one edge, to maximize the stability of the foam and to reduce the work the servo will have to perform.
Another decision we faced was whether to carve the tombstone's design before or after we split it in two. What if the split turned out to be in the wrong place? We'd have wasted all that work. Our solution was to cut it first, then piece it back together, and then carve it.
Another good reason for doing it this way is that you'll want the split to look natural, and to be able to open and close without catching on protrusions in the foam. Nichrome can make some pretty crazy curves, many of which don't resemble the way a stone monument would split. However, if you're confident of your nichrome-fu and want to split the tombstone in two after you've made it beautiful, go for it!
back to top Maker Profile: John Baichtal
John Baichtal is a contributing writer to MAKE magazine, Make: Online and the GeekDad blog. He's also a founding member of the Hack Factory in Minneapolis, MN. He's currently finishing up a book about Adult Fans of Lego and looking forward to his next big project.
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