Cheap Motion Activated Coffin





Introduction: Cheap Motion Activated Coffin

This is how I built a coffin that has sound, fog, lights, and a motion activated lid. To watch a video see my photobucket site.

Step 1: Building the Coffin

I started by cutting a piece of plywood to the shape and size of the bottom of the coffin. From there I built a simple frame out of 2x4s. I attached 1x4s to make the exterior of the coffin.

Step 2: Building the Coffin Lid

I started in the center and worked my way out. I made four cross beams to hold the 1x4s in place. After the entire coffin was covered by the 1x4s I cut it to shape with my table saw.

Step 3: Adding Sound, Light and Fog.

I decided to use a power strip for electricity so I mounted it to one of the 2x4s. Then I mounted the fixture that held my two lights and plugged it in the strip. Ater that I mounted the PC speakers in the coffin and plugged them in. The audio was provided by a cd player. All the way to the foot of the coffin I mounted my fog machine which was hooked to a timer.

Step 4: Adding Pnuematics

I used a motion detector to activate my screen door closer air cylinder. To send air to the cylinder I used a washing machine solenoid. To add more movement I activated the solenoid with a 12volt car flasher and a relay.

Step 5: Weather the Wood

I used watered down grey paint and black spray paint to weather the wood on the coffin.



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    That is a great looking coffin you built there. Too bad it got ruined in the flooding of your storage shed. I do have a question if you dont mind me asking. When you say you watered down the grey paint, how much water did you add to how much paint? Was it a 50 50 solution? Thanks!

    1 reply

    I don't remember but I sprayed with my air spray gun It was pretty watered down from what I recall.

    very nice, more details on parts used, sources, and close up pictures of the key assemblies. Thanks!

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    Thanks but during the next year my yard flooded and the shed where the coffin was had about 6 inches of water in it. So all of the mechanical parts were ruined. This year it will be my fog chiller. Here is the mechanical parts.

    the motion detector is set on test mode so it only stays active for like 3 seconds at a time the flasher relay just makes in turn on and off while active

    using the flasher relay does the coffin continuously open and close once activated?

    Its not actually split into 3 directions it is an in and 2 out. In order for the lid to fall back down I needed a way to let the air back out so the other out leg is just a piece of tubing with a regulator on it to control the speed of the air coming out and the speed of the falling action.

    Does anyone have more info on how the solenoid and pneumatics work.

    2 replies

    if it is the valve yuor talking about look around in Google and look for sprinkler hack a mod of turning a sprinkler into a airtight valve pretty handy too i made one :)

    a pneumatic or the air one is like a hydrolic ram and the electric one uses a motor to push it up and a solenoid is sorta like a valve that uses a pin to lift up a valve to let what every your flowing through the valve if your talking about the valve one thats my way i i think thats what it is...

    what is it that releases the air quickly when it shuts off? why is the air supply split into three different directions. Thanks for your info. great Idea.

    May I suggest adding fake skeleton arms and hands to the door of the coffin. It will look like something is trying to escape.


    what's your foto bucet site????

    Cool I like the DIY pneumatic actuator system

    to cut down on the weight, I used L brackets instead of wood at all the joints and the bottom was just nailed into the sides. worked well.

    wow amazing this would be a nice project to try...

    It is too heavy for one person to move and too bulky. The materials could be changed in order to cut down on weight I just used what I had.

    That looks fantastic. I'm curious about the weight of the coffin. Can one person lift and move it? Do you think 2x2's would be strudy enough for the inner framing?

    I already have a fog chiller but is is too big to fit in the coffin. Thanks for the comments

    love it. have you ever thought about making a fog chiller to create a low lying for effect or fog waterfall to spew out of your coffin?