Continuing to be bored, I've provided assembly instructions for those of you who'd like to duplicate my spud gun.
Materials needed:
All PVC (pipe and fittings) is Schedule 40. This is important.
1 - 4" Wye
1 - 3" x 4" Bushing (not coupling)
1 - 2" x 3" Bushing (not coupling)
1 - Length of 2" PVC Tubing, approximately 40" long. (you can go longer but the gun becomes more difficult to handle. using a shorter barrel can sacrifice distance.)
2 - 4" cleanouts with plugs.
1 - Replacement gas grill pushbutton ignitor
2 - #14 x 2-1/2" long zinc pan head sheet metal screws.
1 - small piece of spare primary wire (maybe)
tools
11/32" drill bit
five minute epoxy
PVC Glue
Electrical Tape
Screwdriver
Grinder
wire stripper or wire cutters
A broomstick handle, or piece of wood less than 2" wide, and 48" long
Ammo:
All Purpose Potatos (apparently one of the purposes, is ammunition)
Aquanet hair spray (WD-40 is also a good fuel in a pinch)
Apples and Onions also work well.
Step 1: Assemble the PVC pieces as shown in the diagram above, using PVC cement. If you're an idiot, then you should probably test fit all the pieces before you start gluing.
Step 2: Drill a hole approximately the size of your grill igniter as indicated in the diagram. You want it to fit tightly so dont drill it too big. if you have to, start small and slowly work it bigger.
Step 3: use the two part epoxy to set the igniter in the hole, try to cover the threads on the igniter the best you can. The tighter the igniter is set, the better. Remember, it has to withstand the force of explosion.
Step 4: OPTIONAL: grind down the tips of the machine screws so that they taper to a perfect point, smooth for about the last half inch or so. This will make it easier to clean the contacts when they get gummed up.
Step 5: predrill two holes on perfectly opposite sides of the back of straight 4" hole. see the pictures for clarification.
http://www.zeldaclassic.com/eckels/spudgun/DSC00739.JPG_s.jpg
http://www.zeldaclassic.com/eckels/spudgun/DSC00740.JPG_s.jpg
http://www.zeldaclassic.com/eckels/spudgun/DSC00741.JPG_s.jpg
http://www.zeldaclassic.com/eckels/spudgun/DSC00742.JPG_s.jpg
Thread your two machine screws into these holes - the tips of each screw should sit about 1/4" - 3/8" of an inch apart when fully inserted.
Step 6: Drill two small holes for your igniter wires to come out of the back of the PVC wye. Two is better than one, because you can get the wires to fit snugly when you only have on in each. One hole for both would leave a gap - unless it's filled with caulk or something else. my way is quicker.
Step 7: connect your igniter wires to the igniter and wrap the igniter with electrical tape. The electrical tape prevents the hairspray from caking up on the ingiter, therefore preventing your spark.
Step 8: Run the wires out the two holes you drilled, and connect one to each screw. You may need a bit of extra wire, depending on the length of your igniter wires and where you put the screws. You COULD solder the wire to the screws, or something fancy, but i just tightened the screws down on the bare wire and it worked fine.
Step 9: Cover the contacts on the outside of the tube with electrical tape. I also covered up the wires to be sure not to tug at them. If you dont cover the contacts, you could get shocked. It's not going to hurt you, it just wont fire the gun.
Firing the gun:
A Take a potato that is larger in diameter than 2", and jam it into the barrel. It will take some coaxing. The sides will tear, and you'll be left with a half-skin, or whatever. As long as the potato creates an air-tight seal, you're gold.
B Using the broomstick (or whatever stick) push the potato to the very back of the barrel. It will stop when it's all the way in the back. The bushing provides this stop.
C Test your igniter to make sure you're getting a spark.
D Cap the trigger side of the chamber with one of the plugs.
E Fill the chamber with hairspray (about five seconds of spray is plenty), and quickly cap with the other plug.
F Aim and FIRE!
G Watch in amazement
H Get a beer and do it again!
WARNING: Never fire at people or animals or anything worth more than a dollar. This gun will turn a trashcan inside out. It would put a hole in a wall, and some serious holes in your windshield or car doors.
