October 7, 2005

I spent this afternoon refining the design of my grave jumper.  I am starting to call it my pop-up platform since the new design is very versatile.  I eliminated all of the hardware that I used in the last design.  The entire armature is made out of PVC and no longer uses the bolts and nuts that the earlier design required.  Part of the reason for this change is that it was difficult to keep everything tightened and working smoothly.  The main reason though was that I wanted to be able to completely submerge the pop-up platform under water for my toxic barrel prop and not have to worry about the metal hardware.

The basic design of the new pop-up platform is the same as my grave jumper.  I just eliminated the dual levers and replaced them with a single lever that uses the center PVC pipe as a shaft to rotate on.  The action is much smoother than the previous bolt and nut design and I believe that it will hold up many years longer without any adjustment or need to retighten nuts. I glued the entire assembly together except the rotating sections and where the head/shoulders attach.  I felt that at some point in the future I might need to replace the PVC pieces that rub together and I definitely want to be able to change the "monster" that I attach, so I left them unglued and fastened them with some self tapping stainless steel screws.
As you can see, the head on this design is quite a bit higher off the ground to begin with.  I have extended the supports for the shoulders so that the head sits just below the rim of my toxic barrel.  By mounting the head higher, I was able to shorten the length of the lever arms (so the pop-up platform would fit in the barrel) and still get the height I wanted out of the top of the barrel...
I set the relief valve at a very low pressure so that the prop returns to neutral very slowly.  I like the idea of a big scare and then a slow return.  I think this will be especially creepy if I end up filling the barrel with water. Click on the image to the right to check out the video of my testing. Eventually I'll dress the mechanism to look like a toxic waste victim and add the arms and hands.  For the moment you'll just have to use your imagination.	(click on image for barrel test video)

Tomorrow the construction continues...  A lot of testing needs to be done to determine if the toxic barrel pop-up will work properly in water and I need to get some more supplies to make that determination.