Build A Net Gun

Step 7 Build Launcher Assembly

In this step we will build the launcher assembly. When finished, the whole assembly is threaded into the outlet side of the trigger valve assembly. No pipe dope or Teflon tape is needed as this section of the gun isn't holding pressure, the air from the pressure chamber will only be present for an instant so small leaks aren't a problem. For that matter, just line up the PVC parts that need to be assembled and push together, don't bother twisting, as proper alignment is paramount for this section. It is helpful to use a good bit of glue as this gives you a few more seconds to tweak the alignment before it sets, just have some towels handy to wipe up the excess that is squeezed out.

• Launcher assembly supplies

4 bent launcher arms from step 6
1 1/2" cross
2 1/2" tee
4 1/2" street elbows
4 1-1/2" pieces of 1/2" pipe the coupler joiners
1 1-1/2" pipe 9" long
1 1-1/2" coupler
** 1 1-1/2" to 1/2" reducing bushings
** 1" MPT to 1/2" slip
PVC primer and glue
A nickel
A drill and 3/16" bit

^{** these transitions usually can't be made with one adapter, just make sure the starting and ending measurements are correct.}

Assembly

• Fig 1 is a view of all the components needed for this step.
• Assemble and glue the adapters needed to go from 1" MPT fitting to 1/2" slip. Glue this to the 1/2" cross, using one coupler joiner.
• Glue one 1/2" tee perpendicular to the axis of the cross with a coupler joiner. Repeat for the other side.
• Glue the 1-1/2" coupler to the 9" length of 1-1/2" pipe. Glue the bushings needed to go from 1 1/2" pipe to 1/2". Drill a 3/16" hole in the center of the nickel and force it into the 1/2" bushing that is at the base of the net holder. This nickel is an air flow restrictor, it allows a little bit of air in to the net holder to assist with net deployment. Pin this nickel in place by gluing in a coupler joiner. Glue net holder assembly to cross.
• At this point I would NOT glue the street elbows into the tees, or the launcher arms into the elbows. Line up the street elbows by sighting down the launcher arm as in Fig 2, Figs 3 and 4 show incorrect alignment. Once aligned, firmly tap the street elbows on the launcher arms and then tap those into the four tee outlets. This will allow you to adjust the angles, or replace the launcher arms, before final gluing.
• Align the arms such that the bottom two are parallel with the net holder tube. The top two arms should be twice the angle of your launcher arms. Example, if you used 19 degree launcher arms, the upper two arms should be at an angle of 38 degrees relative to the lower arms.
• Thread the launcher assembly onto the trigger valve/pressure chamber assembly from step 5, horizontal launcher arms down, angled arms up.

Comments

[tim789]

how much psi would i need with the pvc tractor things

[Schmidtn]

What purpose does the nickel with a hole in it serve? I accidentally forgot to drill the hole before I glued it up.

[crispyjones]

It helps shoot the net out of the holder which seems to help deployment, though I may be imagining this benefit. I built a cap for the end of the net holder by heat shrinking the bottom of a water bottle to the opening, this cap keeps the net securely in place. The hole in the nickel allows air pressure to blow the cap off so I don't have to remember to remove it. I will post a brief writeup of the cap build at some point. Bottom line, I don't think the lack of a hole will have much effect.

[cowboy93]

or would it just add unwanted weight and make it unwieldy