Help With foot activator

[Ted Murphy]

Hello,

I recently purchased this "mousetrap" activator. It is a square steel box that has two pieces of 3/4" plywood on it, hinged front and back. When you lift the wood up, you see two metal rods on a spring. Each rod can activate a different device, though with the force it applies, I suspect 4 or more is a possibility.

The two rods have some flat 1/4" steel welded on the ends. When the spring is compressed, these flats are cocked against some round bar stock. The flats stick up a bit and the boards are then set on top of them. When weight is applied, the flats are rotated off the bar stock and "WHAP!" the device activates.

Some problems

1.) It sets too lightly. On several occasions, I have seen a piece of fired brass land on the plywood and set the activator off. It is very easy to set off.

2.) It also goes off by itself.

I really do not believe in re-engineering someone else's design but it is a frustrating prop to say the least. Since we are using this on a concrete floor we are considering mounting it on some plywood with a non skid surface mounted to the bottom. The metal frame slides about too easily and makes for a fun reset time. What I was thinking about doing was attach to the wood some kind of spring or other compressible item that will take the weight of the two 3/4" plywood pieces off the metal flats. I am hoping this will increase reliability.

Does anyone else have experience with this kind of device. I would post pictures but I am unsure if this would violate forum rules as someone may be able to make out the manufacturer's name on the side.

Also, if you have such a device, be VERY careful how you reset it. If the rod slips off and activates early and your hand still is in the way, it will break fingers.

Ted

[dshooter3]

I made one of those, my solution was adjust the the angle that holds the springs back. One other solution may to add some tension to the hinges. Pinch the frame or add some set-screws to add friction

[open17]

Drill a couple of shallow holes in the bottom of the plywood in the corners away from the hinge.

If you get the right size hole, you can kind of "screw in" a short chunk of spring. Make it

long enough to help hold up the plywood a bit.

We use worn out 1911 recoil springs.

[Tom Mainus]

I bought one from R&R and had similiar problems. The thing came with such a beautiful powder coat job that the rods would slide off of the tabs that they set on. I took a belt sander and roughed up the surfaces where they meet and that solved that problem. If it goes off by itself are you using both rods to reset it? Whether both rods are being used to activate stuff or not, you have to reset both every time or the plywood top is to heavy for just one rod to be set.

Tom

[Flexmoney]

Post your pics, Ted. No worries.

I ran one at the Area 8 match this year on the stage that I CRO'ed. It was actually my first time (ever) resetting one.

I was told to reset both arms each time. I did so. It worked perfectly for the whole multi-day match.

That is about all I know of them.

[LPatterson]

Bolt it to a piece of plywood and put skate board tape on the bottom to stop it sliding around.

Increase the weight of the springs, a local purchased one has two springs and is a bear to reset another home made ripoff only has 1 spring and is easy to reset. But even when it is activating one item both rods need to be set.

[ajg308]

We have the same out our club. I agree with the other poster about the powder coat. Grind that off and also cut a small notch in the flat steel. That notch will create enough tension to hold the plate in place.

[Ted Murphy]

Thank you all for the information

I roughed up the paint on the bearing surfaces with a dremel and a coarse sanding wheel. It ran great after that.

Ted