Making a Basic Combustion Cannon
Posted: Fri Feb 16, 2007 6:59 am
Alright. I already posted this on Sgort's forum so I went ahead and decided to post it here. This is eventually gonna be on my web site so don't think I copied it. 
<B>Making Your Standard Combustion Cannon</B>
Alrighty. I knew I couldn't just make ALL my tutorials about how to join pipe and what not. So, I decided to start off this line of tutorials with instructions on how to make a basic combustion cannon. This cannon is a simple breech-loading, aerosol-fueled combustion with lantern sparker ignition. Basic as they come. So, let's start.
<U><B>MATERIALS</B></U>
15" of 3" SCH-40 PVC pipe
3" cleanout cap
3" female adapter
3" coupling
3x2" flush bushing
2" cleanout adapter, (spigot x FNPT)
Lantern igniter, (Ozark Trails, from Wally-World)
2" male adapter
2x1-1/2" flush bushing
54" of 1-1/2" SCH-40 PVC pipe
<B><U>Construction</U></B>
Please refer to the back of the can of cement for instructions on solvent welding.
#1: Solvent weld the 3" female adapter to one end of the 15" length of 3" pipe.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#2: Solvent weld the 3" coupling to the other end of 3" pipe.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#3: Solvent weld the 3x2" flush bushing into the other socket of the 3" coupling.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#4: Solvent weld the 2" cleanout into the 2" slip of the 3x2" bushing. Wait 15 minutes after this step to allow all joints to set.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#5: Drill a 1/4" hole where the 3" female adapter overlaps the 3" pipe.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#6: Take the silver nut, sheet metal bracket, and washer off the screw, along with the knurled knob.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#7: Using vice grips, thread the brass nut from the lantern igniter into the 1/4" hole.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#8: Insert the lantern sparker through the nut from the inside of the launcher. The hardest part here is getting the wire inside the nut to line up with the stupid little groove in the stem of the igniter. After inserted, attach the knob back onto the stem.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#9: Now you're ready to make the barrel for the launcher. For this, you will need the male adapter, 2x1-1/2" bushing, and 54" length of 1-1/2" pipe.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#10: Grind out the stop in the bottom of the bushing. You can see the stop in the image above.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#11: Now comes the difficult part. There is a taper to the back of the bushing. Use a dremel or file to bore out and remove this taper. You can do this by removing a little material, checking the fit, removing more, and checking the fit again until the bushing slides completely over the pipe without twisting or forcing it.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#12: Mark the barrel to where you can slide both the bushing in the male adapter and have about an inch or an inch-and-a-half extending past the male threads. Solvent weld the bushing into the male adapter and prime the barrel where you marked and the inside of the bushing. Apply glue only to the spot on the barrel, (not in the bushing), and push the bushing onto the pipe until it overlaps the glue and twist 1/4 turn to spread the cement.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#13: Sharpen the breech to form a slug-cutter and the construction of your cannon is complete! Just remember to wait 24 hours for the cement to fully cure before firing. A good thing about having a threaded barrel is that you can have interchangeable barrels, like the 2x33" one shown below.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
That's it! I hope you found this tutorial useful. As for usage, simply load a spud, open the cleanout cap on the back, spray in your fuel, close the cap, and then twist (flick) the igniter. Make sure to vent out all the combustion gases before reloading and spraying in more fuel.
<B>Making Your Standard Combustion Cannon</B>
Alrighty. I knew I couldn't just make ALL my tutorials about how to join pipe and what not. So, I decided to start off this line of tutorials with instructions on how to make a basic combustion cannon. This cannon is a simple breech-loading, aerosol-fueled combustion with lantern sparker ignition. Basic as they come. So, let's start.
<U><B>MATERIALS</B></U>
15" of 3" SCH-40 PVC pipe
3" cleanout cap
3" female adapter
3" coupling
3x2" flush bushing
2" cleanout adapter, (spigot x FNPT)
Lantern igniter, (Ozark Trails, from Wally-World)
2" male adapter
2x1-1/2" flush bushing
54" of 1-1/2" SCH-40 PVC pipe
<B><U>Construction</U></B>
Please refer to the back of the can of cement for instructions on solvent welding.
#1: Solvent weld the 3" female adapter to one end of the 15" length of 3" pipe.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#2: Solvent weld the 3" coupling to the other end of 3" pipe.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#3: Solvent weld the 3x2" flush bushing into the other socket of the 3" coupling.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#4: Solvent weld the 2" cleanout into the 2" slip of the 3x2" bushing. Wait 15 minutes after this step to allow all joints to set.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#5: Drill a 1/4" hole where the 3" female adapter overlaps the 3" pipe.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#6: Take the silver nut, sheet metal bracket, and washer off the screw, along with the knurled knob.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#7: Using vice grips, thread the brass nut from the lantern igniter into the 1/4" hole.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#8: Insert the lantern sparker through the nut from the inside of the launcher. The hardest part here is getting the wire inside the nut to line up with the stupid little groove in the stem of the igniter. After inserted, attach the knob back onto the stem.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#9: Now you're ready to make the barrel for the launcher. For this, you will need the male adapter, 2x1-1/2" bushing, and 54" length of 1-1/2" pipe.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#10: Grind out the stop in the bottom of the bushing. You can see the stop in the image above.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#11: Now comes the difficult part. There is a taper to the back of the bushing. Use a dremel or file to bore out and remove this taper. You can do this by removing a little material, checking the fit, removing more, and checking the fit again until the bushing slides completely over the pipe without twisting or forcing it.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#12: Mark the barrel to where you can slide both the bushing in the male adapter and have about an inch or an inch-and-a-half extending past the male threads. Solvent weld the bushing into the male adapter and prime the barrel where you marked and the inside of the bushing. Apply glue only to the spot on the barrel, (not in the bushing), and push the bushing onto the pipe until it overlaps the glue and twist 1/4 turn to spread the cement.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
#13: Sharpen the breech to form a slug-cutter and the construction of your cannon is complete! Just remember to wait 24 hours for the cement to fully cure before firing. A good thing about having a threaded barrel is that you can have interchangeable barrels, like the 2x33" one shown below.
<a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A> <a HREF="http://www.geocities.com/ros_aircannons ... .jpg"><img src="http://www.geocities.com/ros_aircannons ... b.jpg"></A>
That's it! I hope you found this tutorial useful. As for usage, simply load a spud, open the cleanout cap on the back, spray in your fuel, close the cap, and then twist (flick) the igniter. Make sure to vent out all the combustion gases before reloading and spraying in more fuel.
