Perimeter alarm (trip flare) details

Hmm. Well they resized my photo so that you can't read my notes. OK, here's a list:

1. spring assortment Harbor Freight item 67562
2. universal clevis pin assortment Harbor Freight item 67629
3. 3/8x6" steel pipe nipple-drill small hole about 3/8" from end of pipe for one end of spring to go through4. short (5"?) piece of 3/4" pvc pipe
5. Federal No. 209A shotshell primers (fits inside 1/8"xclose brass nipple)
6. Watts A-715 1/8"xclose brass pipe nipple
7. 1/2x3/8" reducer coupling
8. Watts A-826 Pipe Bushing 1/2"MIPx1/8"FIP - (I ground the end with the flat corners down all the way to the threads, so that it can be threaded *backwards* into the1/2" end of the reducer coupling.
9. 5/16" bolt - grind head to fit inside 3/8" pipe and cut to 1 1/2" long with with end ground to a 1/8" flat point. (This makes the firing pin.)
10. 11/32x 1 27/32" extension spring from above assortment.
11. 1/4"x2" clevis pin from above assortment. Grind the head off, so that it fits completely inside spring.
12. Hitch pin clip from above assortment. Spread it slightly so that there is no resistance when it is pulled out of clevis pin.

ASSEMBLY:
1. Modified clevis pin fits completely inside spring.
2. Put one end of spring through 3rd hole of clevis pin. (Other end will go through hole drilled in 3/8" pipe)
3. Take a piece of stiff wire and bend the end to hook first hole of clevis pin. (I will make a "flare assembly video" so you can see what I mean.)
4. Insert stiff wire holding clevis pin through end of pipe that has the hole until the unattached end of the spring is near the hole drilled in the pipe. Using some small needle nosed pliers, maneuver the unattached end of the spring through the hole and grab it with another pair of pliers. (You do have 3 hands, don't you?) Trust me. It can be done. Pull any extra wire to the outside and tape with ducttape so that it doesn't go back inside.
5. Pull end of stiff wire until 2nd hole in clevis pin is visible at the other end of the pipe, then insert clevis pin clip through it to keep it from going back into the pipe.
6. Screw the 1/8"xclose brass pipe nipple into 1/2"MIPx1/8"FIP Pipe Bushing.
7. Screw that assembly into the 1/2x3/8" reducer coupling such that the 1/8" pipe nipple is sticking up into the 3/8" end of the 1/2x3/8" reducer coupling. Yes, that's what I said. You may need to make sure that the square end that you ground off is ground down enough so that it doesn't get in the way. Also make sure that it's ground down right up to where the threads start. You might need to use a Dremel and touch it up with a little file. (A little mill file, or a little bastard.)   :)  I did it, so you ought to be able to.
8. Insert a No. 209A shotshell primer into the end of the 1/8" brass pipe nipple. It should fit perfectly.
9. Now screw the entire assembly (now containing a primer) onto the 3/8" pipe nipple. Your trip mechanism is now armed.
10. Duct tape the piece of 3/4" pvc pipe onto the 1/2" end of the 1/2"x3/8" reducer coupling.
11. You can put a couple 30 grain .50 pyrodex pellets inside the pvc pipe, if you wish to make it more visible. *Don't* confine it or it could rupture the pvc pipe.  You could put a balloon over the open end to keep it waterproof, if you wish.
12. Securely attach the alarm device to a tree or something and carefully tie a length of nylon monofilament fishing line (say about 30# test) to the clevis pin clip and tie the other end to something. That is your "trip wire".