Props that activate when weight is taken off them

[Skydiver]

Are there any props that activate when you take the weight off them?

Off the top of my head, I'd love to someday do a Indiana Jones type stage where a series of props are activated by taking the "treasure" from pedestal, but I'm also contemplating a few unloaded gun starts where picking up the gun or magazines would do interesting things as well.

As as alternative to weight, I was also considering magnets. I'm not sure if revolver speedloaders have enough iron in them to have a magnet attracted to them? And what about people who shoot FN's? Is there enough metal in the magazine?

[Jim Norman]

A lever with a weight on it, the weight could be as simple as a revolver speed loader, the lever moves and allows a reed switch to open and this causes the desired activation by means of a battery powered solenoid. Not too hard to imagine.

Or a spring loaded platform where removing a weight allows a piston to rise, pulling a pin that drops an activator weight that starts tings moving.

Neat, Might have to work on that one over the winter.

[jmorris]

Your one forum too low for prop construction but close enough.

I needed a switch to spin up my powered TX star until the shooter began firing at it. The soultion was a 1'x2' aluminum sheet with a 3/4" break on one edge that had a SPDT limit switch mounted to it then in the middle another bend so it came back over the switch.

Once the shooter made ready he/she placed the pistol on the plate and the star spun up. At the beep, pick up the gun and killed the power, after 20 seconds or so it would coast to rest and become a normal TX star.

I don't have any photos of the switch but could take some if it doesn't I was not clear enough. The star is like this.

If you were looking for something more along the lines of a rope puller, you could build a reverse pressure pad but it woud take a bit of tweeking springs and such to get it set just right unless you were removing a lot of weight.

[jmorris]

After reading my post a photo might be worth while, pretty much like below. If you use the NO contact on the switch it will activate when you put weight on if you use the NC contact it will activate when you remove the weight.