Water Bottle Rocket Launcher Parts & Instructions (See next page for Illustrated Parts List) Ver. 2.0 May 28, 2014 Steve Maher

Transcription

1 CUB SCOUT PACK 629 San Diego (Rancho Penasquitos), Calif. Water Bottle Rocket Launcher Parts & Instructions (See next page for Illustrated Parts List) Ver. 2.0 May 28, 2014 Steve Maher (May 2014) Qty SKU Price ea. Description FROM HOME DEPOT: $1.27 1/2" PVC Plastic Tee, FPT threaded $6.61 1/2" Galvanized Iron Floor Flange, FPT $1.34 1/2" Galvanized Iron 2" Nipple $2.70 LFA-15 brass Compression Adapter, 1/4" OD to 1/8" FIP Pipe $6.66 LFA-25 Brass Compression Adapter, 1/4" OD to 1/2" MIP Pipe 1 bx $2.27 O-ring, #215, 1" O.D., 3/4" I.D., 1.8" thick $1.26 1/2" PVC riser nipple, 12" long, threaded $1.27 Teflon pipe-joint tape (you actually only need about 30") $ foot Polyethylene tubing, 1/4" OD, 0.170" ID, 140 PSI $2.77 3/16" Round Steel Rod, Zinc-plated, 36" long 1 pk $4.56 Epoxy Glue (any brand, comes in 2 bottles, "5-minute" hardens quicker) $7.53 1x6 Common Wood board, 8 ft. long $1.18/9pack #6 x 1-1/2" Phillips-head sheet metal screws $1.18/6pack #12 x 1" Phillips-head sheet metal screws $1.18/4pack 1/4" -20 x 1-1/2" bolt $1.18/4pack 1/4" -20 wing nut 12?? $1.18/6pack 1/4" fender washer FROM NAPA AUTO PARTS: $1.34 Industrial Tank Valve (tire valve), Schrader, 1/8" MNPT, any length FROM HOBBY SHOP: 1 $ /32" Brass tube, 12" long 1 $6.00 1/16" (or 0.064") thick Aluminum Sheet Metal, 12" long by 6" wide Tools needed (approximate, use what you got) * Hacksaw * Crosscut or Toolbox saw * Cordless or corded drill, or eggbeater-type * Vise-grip pliers * Crescent wrench, 6" or larger * #2 Phillips-head screwdriver * Workbench Vise * Scissors, knife, or razor blade

2 Illustrated Parts List 1/2" PVC Plastic Tee, FPT threaded 1/2" Galvanized Iron Floor Flange, FPT 1/2" Galvanized Iron 2" Nipple LFA-15 brass Compression Adapter, LFA-25 Brass Compression Adapter, 1/2" PVC plastic nipple, 12" long 1/4" OD to 1/8" FIP Pipe 1/4" OD to 1/2" MIP Pipe Epoxy glue (any brand) 1x6 Common Pine Board Tank 19/32" Brass Teflon tape Valve 1/8" NPT Tubing, 12" long O-ring, 3/4" ID, 13/16" OD, 25-foot Polyethylene tubing, 3/16" Round Steel Rod, 1/4" -20 Nut 1/4" Washer neoprene rubber 1/4" OD, 0.170" ID, 140 PSI Zinc-plated, 36" long #6 x 1-1/2" Phillips-head #12 x 1in. Phillips-head 1/4"-20 bolt, Phillips-head 1/4" Fender Washer sheet metal screws sheet metal screws

3 1.) Build the Launch Tube (a) Cut a 2-inch piece off the 19/32" brass tube. Use a file to smooth the rough, sharp edge of the 2-inch piece of brass tubing. (b) Cut off the 12-inch gray plastic PVC nipple, to get a piece 8 inches long. Use a file to clean off the burrs from the cut end of the 8-inch piece. Discard the shorter piece. (c) The 8" piece of gray plastic PVC nipple, has threads on one end and no threads on the other end. Cut off the threaded end, 1-1/2 inches from the end. Now you have one piece approx. 6-1/2" long and one piece 1-1/2" long. Use a file to clean off the burrs from BOTH pieces' cut ends. (d) Mix a small amount of Epoxy glue and use a toothpick or nail to coat the inside of the 6-1/2" piece where you just cut it, and also to coat the inside of the 1-1/2" piece you just cut (not the threaded end), with epoxy glue. Slide the 2" brass tube from Step (a) above, halfway into the 1-1/2" piece of the gray PVC pipe where the glue is. Slide the 6-1/2" piece of gray PVC tube onto the end of the brass tube that is sticking out of the other pipe. Push the two gray sections of PVC pipe toward each other, but stop when there is a 1/8" gap between them, so you can see the brass tube in the gap. (e) Set the Launch Tube aside to let the glue harden.

4 2.) Install Launch Tube base (a) Cut the 1x6 Common Pine Board into five pieces: Three are 24" long, two are 5-1/2" long. (b) Place the Galvanized Floor Flange in the center of one of the 24"-long pieces. Mark the holes with a pencil, and drill them with a 3/32" drill. (c) Mix a medium amount of epoxy glue, and spread it in a blob approx. 1-1/2" diameter between the screw holes. This will seal the bottom of the flange to the wood, so air pressure will not leak out. (d) Place the flange on the board with the screw holes lines up, press it down into the glue (don't get any glue on the pipe threads), and install it with four #12 x 1" screws. Let the glue harden. 3.) Assemble the Air Hose (a) Install the LFA-15 Compression Adapter on one end of the plastic Polyethylene air tube, as follows: (1) Unscrew the cap from the adapter (2) Slide the brass cap onto the plastic tube, backward so the threads point back toward the end of the plastic tube.

5 (3) Push the brass insert into the plastic tube (4) Press the plastic tube with the insert, firmly into the Compression Adapter (5) screw the brass cap onto the adapter so that it traps the plastic tube and insert. (6) Tighten the brass cap FIRMLY onto the adapter. (b) In a similar way, install the LFA-25 Compression Adapter on the other end of the plastic Polyethylene tube. (c) Cut a 1-1/2" piece of Teflon Tape, and wrap it around the threads of the Tank Valve. Then screw the Tank Valve into the LFA-15 Compression adapter. Tighten snugly, but do not overtighten. 4.) Install Launch Tube Mount and Air Hose (a) Cut a 3" length of Teflon Tape, and wrap it around the threads on one end of the Galvanized Iron 1/2" nipple. Screw that end into the center of the Floor Flange on the pine board, and tighten snugly. (b) Cut another 3" piece of Teflon Tape, and wrap it around the other end of the Galvanized Iron 2" nipple. Then screw the PVC Plastic Tee onto that end of the Galvanized Iron Nipple. Turn it until it is fairly snug, then keep turning it until the side opening of the Tee, points directly toward the end of the board. The Galvanized Iron Nipple might also turn slightly as you do this, that's OK. (c) Cut another 3" length of Teflon Tape, and wrap it around the large, threaded end of the LFA-25 Compression Adapter that you already installed on the plastic tube. Then screw that end of the LFA-25 into the side opening (not the top) of the PVC Plastic Tee, and turn it until snug. You might have to ask someone to hold the plastic hose, and keep turning it as you screw in the LFA-25 adapter to the Tee, so you don't twist the hose up like a candy cane. 5.) Build the Wood Frame (a) Use #6 x 1-1/2in. screws to fasten the other two 24" sections of Pine Board onto the base 24" section, to form two wooden walls on either side of the Launch Tube Mount. You can also use Epoxy Glue (or a good wood glue like Titebond, don't use Elmer's glue because Elmer's melts in water!) to glue these wood pieces together, if you want. Make sure the three wood pieces are installed TIGHTLY together, with no gaps. Let the glue harden if you used glue. (b) Place the two 5-1/2" wood pieces on top of the 24" wood walls, 3 inches apart, on either side of the Launch Tube Assembly. (Each wood piece is 1-1/2" away from the center of the launch tube assembly). Make sure the grain of the wood goes ACROSS the gap, from one wall to the other. Fasten each wood piece in place with six of the #6 x 1-1/2" screws. Make sure they are fastened down TIGHTLY, with no gaps.

6 6.) Install Launch Tube (a) When all epoxy glue is completely hard on the Launch Tube and the Floor Flange, stretch an O-ring around the end of the Launch Tube. Roll it down to the 1/8" gap where the brass tube shows, and let it snap into the 1/8" gap. (b) Cut a 3" piece of Teflon Tape, and wrap it around the threads of the end of the Launch Tube. Then screw the Launch Tube into the top opening of the PVC Plastic Tee, between the wood walls. Make sure the side opening of the Tee, continues to point directly at the end of the wood frame. Screw the Launch Tube in snugly. 7.) Make the Lock (a) Cut a piece from the 3/16 Round Steel Rod that is 20" long. (b) Bend the 20" piece into a narrow V shape, as shown: 8.) Make the Lock Guide (a) Cut a piece from the 3/16" Round Steel Rod that is 9" long. (b) Make four bends in it, as shown in the "Front View" below. (c) Then bend the lower prongs forward, so that the Lock Guide sits flat on the wood frame, as shown in the "Side View" below.

7 Rocket locked, ready to launch Rocket released, away she goes! (***NOTE: Lock Guide and Trigger Piece shown here, are slightly different from simpler ones in plan) 9.) Make the Trigger Piece (a) From the 1/16" Aluminum sheet metal, cut a piece that is 3" long and 2" wide. Use the file to smooth off the cut edged, so they are no longer rough or sharp. Also round off the corners so they are no longer sharp. (b) Drill one 1/4" hole in the middle of one of the 2" wide edges, 1/4 of an inch from the edge. Use a larger drill to ream the edges of the hole and remove any sharpness or burrs. (c) Drill five or six 1/4" holes in the opposite 2"-wide edge, 1/4" from the edge, and as close together as possible. Use a larger drill to ream the edges of the holes and remove any sharpness or burrs. (d) Bend the metal piece at a right angle, along the bend line shown. (e) Run a string approx. 25' long, through the single hole, and tie it so that there is an extra 1 foot of length in the "short" end of the string. Then tie a loop approx. 1" in diameter, in the very end of that short end of the string.

8 10.) Install Lock, Lock Guide, and Trigger Piece (a) Drill a 5/16" hole in the middle of the top piece on the wood frame, that sits farthest from the 25-ft. plastic air hose. (b) Put a 1/4" fender washer on a 1/4" -20 by 1-1/2" bolt. The put the bolt into the 5/16" hole so that it comes out the bottom of the wood piece. Put a 1/4" washer and 1/4" -20 nut on the bolt under the wood piece, but don't tighten yet. (c) Slide the V-shaped Lock onto the bolt, under the fender washer. Make sure one prong of the lock goes to either side of the launch tube. Slide the Lock all the way until the point of the V touches the bolt. Then tighten the nut on the bolt snugly, but don't overtighten. (d) Take the Trigger piece with the 25' string attached, and slip the loop in the short end of the string, over the Lock Guide rod. (e) Mount the Lock Guide on top of the other wood piece on top of the wood frame, this time directly over the plastic air hose. Make sure both prongs of the Lock go under the Lock Guide, above the wood piece, and stick out at least 1" past the Lock Guide. Drill two 1/8" holes, one inside each "right angle" bend at the end of the Lock Guide. Use two #12 x 1" sheet metal screws (one at each and of the Lock Guide), to fasten the Lock Guide to the top of the wood piece, to hold down the prongs of the Lock.