Thursday, August 25, 2011

Trap Trigger - Pressure Plate

Alright, now that I've used them I have no problem talking about the design I made for a pressure plate trap trigger.

It uses the basic pressure plate concept, where there are two solid pieces with some sort of material that compresses in between. The trigger itself was a dog toy squeaker, but there are a number of electrical triggers that could also be used on something like this.

The reason we use two solid pieces is to allow for uniform compression when any part is stepped on. In the past we just used the squeakers, but they're awfully small and easy to lose. This trap basically created a 4" x 4" squeaker trap.

For the two outer pieces, I used the backing for an electrical outlet box. For the inner piece, I used the standard blue camp foam which I attached with tape and spray adhesive. I had to cut out a shape to allow for the squeaker and a path for the air/sound to escape. I taped it up with black gaffer's tape, and used that as the hinge between the top and bottom.

After all was said and done, the trigger cost about $1.50 - $2.00 to make (not including the squeaker), but has nice heft, is easy to set up, and is small enough to be hard to find, and is simple to disarm. All things I like to have in a LARP trap.

I'll try and get some pictures later so you can see the results.


  1. Mark Henry ~MariusAugust 25, 2011 at 10:31 AM

    Sounds awesome Bill. LARPs need more traps, it's a nice unexpected element in any encounter. The major downfall is the time to set them up, your pressure plate looks like it would be throw on ground and done which is amazing. Last event I wasted an hour setting up a trap mod in the dark that never got ran....ugh.

  2. How did you end up implementing the traps? For example did you have NPCs calling the damage or were the PCS told of the traps & damage ahead of time?

  3. On this particular module, the PCs were informed that traps existed and what the effect would be. Normally, though, the traps themselves would have an effect tag on them that doesn't go off until the player looks at it (since Exiles doesn't have many AoE traps).