| Step 3: Assembling the Launcher Now you get to stick all the stuff together, using pipe glue and tape and more solder if you like! Just don't breathe too much pipe glue solvent...it'll make you nuts! I Chamber Assembly: Prime both ends of the 4" pipe, also priming the 4" bushing, both 4" coupler sockets, and 4" slip on the adapter. DO NOT get any primer on the adapter threads! Immediately apply pipe cement to the three primed 4" fittings, then LIBERALLY to both ends of the 4" pipe. Start both the coupler and adapter fittings on the pipe, start the bushing in the coupler, then right the assembly with the threads up, pressing it together with body weight while twisting about 1/2 turn. Hold this position for at least 30 seconds. The pipe ends should bottom each about 1 1/2" inside the fitting socket. If they both do not bottom, either apply more force IMMEDIATELY somehow to get it to, or you are screwed and have to throw it out--start over with that. If the fittings and pipe are properly conditioned this should not be a problem. Wipe up any spilled glue with the rag, but leave a good bead at the external pipe/fittings line. If any glue got on the threads get it out of there as fast as possible! Any glue on your hands should just be left to dry and then peel it off. Using solvent to remove it will just increase your exposure to it. II Electrode Installation: Wait about 10 minutes for the glue to set. Using the proper size drill bit, put two radial holes 90deg apart about 1/2" back from the front edge of the adapter fitting--the plastic here is about 1/2" thick as well. Drive in the two machine screws nearly all the way, leaving about 1/8" between the screw head base and the plastic. The ends may touch or be far apart--the electrode gap will be calibrated after the electrode wires are connected. III Barrel Introduction: Prime one end of the barrel and the 1.5" socket on the bushing. If one end of the barrel was chamfered to a knide, prime the square 'regular' end of the pipe. Apply glue, liberally to the pipe, and press together, again using a 1/4 turn motion to bottom. Hold for 30+ seconds. After releasing place the unit upright for several minutes, to let the glue set a little more. Solvent welding is more of a curing than a drying process. Solvent is lost, hence the term drying, but the action of the solvent effectively cures all those individual plastic parts into one continuous physically joined piece of plastic. Properly done, solvent welds are always stronger than bulk pipe. IV Wire it Up: Tin the two free ends of the electrode wires if possible. With each end bend it around the screw shank, just below the head, in a clockwise manner (you may need needle-nose pliers if the wire is heavy). After the wire is at least 3/4 turn around the shank, tighten the screw, pretty good, biting the wire into the plastic a little. Liberally apply electrical tape, rubber tape, or silicone RTV to the exposed metal areas, as they will shock you all day long if not insulated properly. Before taping tug on the wires a little to make sure they are firmly gripped by the screw head. V Electrode Calibration: Setting the gap is next. The two screws may be in a variety of relative positions, depending on how straight and aligned the holes were drilled. Wearing leather gloves, you now want to somehow create about a 1/4" gap between the screws. This gap does not have to be measured from the very tip of the screw, and the spark will find the shortest route possible. Bend only one screw if possible, and dont bend it around a whole bunch back and forth, or it will get work hardened and break sometime. DO NOT test the spark device yet, as there are still PVC solvent fumes all over the place. Just wind sufficient tape around the ignitor body to fully insulate all metal parts from your hand when you grip it. Lash it to the side of the chamber if you like with electrical or duct tape, just don't press the button yet! |