Halloween is my favorite holiday. Being 16, i'm a little too old to run around and collect candy, but I love staying home handing out candy to little kids and trying to scare them. We usually decorate our yard with card board like tombstones to create a grave yard. This year, however, I had some extra time and wanted to create something new for my yard. I came up with this idea of a pneumatic tombstone when a button is pushed. Many kids jumped when they saw it in action, and I got a lot of compliments. Most of the parts can be found in your garage, or are relatively cheap.
Step 1: Parts
I had most of these in my garage. I only had to borrow the solenoid valve from my grandfather.
* Air compressor
* at least 3'x18" plywood sheet
* wood screws
* nuts and bolts
* old bike pump (or pnuematic cylinder)
* 2 old t-shirts
* tape (masking, packing, or duct)
* solenoid valve
* air hoses
* extinsion cord with switch (or switch plugged into it)
* mask (preferrably scary)
* bungee cord
Step 2: Frame
The frame is a basic "L" shape. This whole project is mostly your decisions, such as size and mask choice, but i'm using what I made it with.
I cut the 3'x18" into a 1'x18" and 2'x18"
I then assembled them in an L shape with the 2'x18" perpendicular to the ground and the 1'x18" acting as the base.
I don't have a great picture for this. sorry
Step 3: Shaping the "Head"
In order to have a head, I had to create one. I didn't have any extra heads laying around. If you have a styrofoam sphere or something like that, it may work. I made the head by taking the 2 t-shirts and wrapping them in a ball tightly. I then covered the whole thing in packing tape. This made a surprisingly dense head that seemed to work well.
Step 4: Attaching the Cylinder
You must measure what the diameter of your head is. This will determine how far to place the cylinder. I made this mistake and had to fix it.
Once you know the diameter, add one inch. This is about how far away the cylinder should be from the front of the base. Mine was about 5 inches so I put my bike pump about 6 inches from the front. Use the assortment of nuts and bolts to attach the bike pump to the base. The size of the bolts depends on the model of your pump.
Step 5: Attach Head
Now that you have the pump attached to the base, you must put the head on. This is the part that pops out and hopefully scares people. All I did was tape the head onto the handle of the pump (take off the handle if its too big and just tape it to the shaft). I put the wig on the head, then put the mask overtop the head. The elastic strap on the mask should stay on the head securly.
Step 6: Attach Rope
After the head is securly on the pump, you need to take the bungee cord and rope. Attach the bungee cord to the back of your head, or to the handle. Use the rope to hook onto the otherside of the bungee cord. When the pump is extended all the way, the end of the rope should be slighly smaller than the length. This way, whenever the head pops up, the bungee cord starts to stretch a little so the head is pulled back down when the compressed air is turned off. Attach the other side of the rope to the base with a screw or s hook.
Step 7: Bringing in the Power
I used a one hp 3 gallon air compressor to power my project. I set the regulator on 30 psi. This seemed to work perfectly for me with the pump I used but experiment with yours to get a good combination. However make sure you do not exceed the max psi on the pump. Hook up an air hose to the air outlet on your air compressor and attach the other side to the input of the solenoid valve. If you do not have a solenoid valve, you can use a normal hand valve to allow the air to get through and cut it off. Attach the output of the solenoid valve to the hose on the bike pump.
Step 8: Powering It Up
Plug the solenoid into a switch controlled outlet. I used a power strip with a switch. Then, plug the switch into an outlet. Turn it on and listen to make sure the solenoid clicks. Turn on the compressor and let it compress. Once it shuts off, flip the switch on the solenoid. Hopefully, the head pops up! If it works, paint it and make it look creepy, then put it outside to scare trick-or-treaters!