Here it is $65 with no controller or sound
It is made of 3/4" PVC and 1/2" pvc pistons OSH, I use a Prop 1($40) with sound card ($8). The pistons unscrew and I changed out the old 'O'ring with 2 new 'O' rings (13/16" I.D. x 3/32" wall OSH part # 0547) and vaseline for lubrication.

here are picts

pvc Ground Breaker pictures by snix911 - Photobucket

and a video

also here is a video of my yard at night


Snix
"they're so scared to be out there"

Here it is naked on the first test


Snix
"they're so scared to be out there"

wow!!! great movement on the gb!!!

Would love your plans or a tutorial on the complete build.

I want to see how the pistons were set up and the how to. Looks like a manic jack in the box!

__________________
Stay scary

Please share, it is awesome!!!

The pistons are from OSH, used to fix PVC breaks easily and at $3 each instead
of $30 they seem to work fine as they only need to work for a few hours a year.
I did need to replace the 'O-ring and use Vaseline to lubricate and it uses
gravity to come down.
Making it with pvc is very strong , lightweight and water proof. It uses 25 lbs. of air pressure.

I will post some kind of a "how to" in a week or so.


Snix
"they're so scared to be out there"

Looks great! I have always been leary of using PVC for air, but it seems to work well for you..

For those that don't know, OSH is a west coast hardware store, short for Orchard Supply Hardware.

__________________
I thought I heard something.

And there is a reason to be leary of using PVC with air, it's not made for that application. There is some from what I've heard but is extremely expensive and hard to locate. Any manufacturer of PVC will tell you it is not made for use with air.

__________________
Money won't buy you happiness, but it will buy me another case of beer

Wow, I love the ground breaker. That thing is pretty startling and fun to watch.

__________________
"Where are the songs of spring? Ay, where are they?
Think not of them, thou hast thy music too"- John Keats "To Autumn"