Instructables.com - Build A Net Gun

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Build A Net Gun
by crispyjones on August 7, 2008
Table of Contents
Build A Net Gun .
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. 1
Intro: Build A Net Gun .
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. 2
Step 1: Materials .
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. 2
Step 2: Net Procurement And Math .
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. 4
Optional Net Math Section .
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. 4
Alternate Net Substitution .
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. 4
File Downloads .
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. 5
Step 3: Build The Pressure Chamber .
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. 5
Step 4: Build The Trigger Valve Assembly .
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. 6
Step 5: Assemble And Test Valve and Pressure Chamber .
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. 8
Step 6: Bend Launcher Arms .
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. 9
File Downloads .
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. 11
Step 7: Build Launcher Assembly .
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. 11
Step 8: Assemble Tractors .
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. 13
Step 9: Assemble Net .
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. 15
Step 10: Loading And Firing The Netgun .
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. 17
Step 11: Et cetera .
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. 19
Mechanical Trigger Safety .
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. 19
Tennis Ball Launcher .
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. 19
Related Instructables .
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. 21
Comments .
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. 21

Intro: Build A Net Gun
I will show you how to build a net gun out of materials available at any big box home improvement store. This net gun is capable of firing a 90 square foot net 15 to 25
feet using 80-100 psi of compressed air. The net is reusable, assuming your prey doesn't destroy or run off with it. The launcher section is modular and can be removed
in case you want to use a different design or add attachments. Thread on some 1" PVC pipe and you have a Christmas Cannon, or check step 11 for how to build a
tennis ball launching attachment.
The net gun is similar to many pneumatic launchers, but instead of launching a single projectile, it launches four tractors that pull the net through the air. The tractors are
based on the fact that the neck of a standard soda bottle fits very well over the outside of 1/2" PVC pipe. The cost to build this will range from approximately $40-$75.
Thanks for all your votes in the Craftsman contest, happy netting. Please check out my slooowly developing website related to netguns at waxedmoustache.com.
Image Notes
1. Yup, it's a net gun. You should have one too.
Step 1: Materials
Before you begin be aware that this project uses PVC pipe in an application it is explicitly not intended for. PVC is meant for water, not pressurized air or other gases.
The problem is not the pressure, this project uses pressures less than half the working pressure of any PVC component, but the failure mode when pressurized by gas. If
the PVC is compromised, by dropping, impact, or other means, it shatters into sharp pieces that are ejected by the pressurized gas. An excellent discussion and
demonstration here, make sure to watch the video through to the end.
Nearly all of these items can be picked up at your local home improvement retailer. It is probably worth buying a full 10' length of 1/2" pipe, for all the other sizes see if
you can buy shorter lengths or scrap. Alternatively, get some friends together, share the costs of the full length pipes, and build a lot of net guns. The tire valves are
available at auto parts stores. The net is addressed in detail in the next step.
SUPPLIES
All PVC fittings are slip fit unless otherwise noted
All PVC pipe and fittings must be SCH-40 (SCHedule 40) unless otherwise noted
All PVC pipe should have a PSI rating of 200 or greater, absolutely no cell core ABS DWV pipe
Pressure chamber parts Fig 1
1 1" MPT (Male Pipe Thread) to 1" slip street elbow
1 1" elbow
1 2" to 1" reducer bushing
1 2" cap
1 2" coupler
1 foot of 1" pipe
minimum 9" length of 2" pipe
**1 valve stem, prefer a .453" as it corresponds to the readily available 7/16" drill bit
optional 1 pressure gauge
**There are two standard size automotive valve stems, one for a rim hole sized .453" the other .625". These two sizes correspond to fractional drill bit sizes of 29/64" and 5/8" respectively, the much more
common 7/16" bit can be substituted in place of the less common 29/64". Additionally, most common drill indexes stop at 7/16" or 1/2" and do not contain the larger 5/8" bit.
Trigger valve parts Fig 2
1 Orbit Model 57461 1" sprinkler valve
1 Blow gun similar to this
1 1/4" NPT hex nipple, like this
Bending jig
3 2"(ish) wood screws
Wood scrap for base, a 16" length of 2x4 should work fine
http://www.instructables.com/id/Build-A-Net-Gun/

Launcher section Fig 3
4 13" lengths of 1/2" pipe
1 1/2" cross
2 1/2" tee
4 1/2" street elbows
4 1-1/2" pieces of 1/2" pipe (coupler joiners)
1 1-1/2" pipe 9" long
1 1-1/2" coupler
**1 1-1/2" to 1/2" reducing bushings
** 1 1" MPT to 1/2" slip
1 nickel
** these transitions usually can't be made with one adapter, just make sure the starting and ending dimensions are correct.
Net
Memphis Net and Twine sku# 263 1lb minimum order is enough to make 7-8 nets
OR a substitute net computed using the net math spreadsheet and instructions in step 2
Nylon mason's twine (#15 or smaller), kite string, or some other thin durable rope
4 per net 16-20oz carbonated soda bottles
4 per net zip ties > 4" long
Hot glue/silicone/wax to pour in bottles to add weight
Optional additional items needed for high performance net tractors
4 per net 3/4" couplers
4 per net 3/4" caps
4 per net 8" lengths of SDR-21(Class 200) 3/4" thinwall PVC note: regular 3/4" SCH40 will NOT work!
4 per net 12" lengths of non-adhesive 1" ID foam pipe insulation. Pipe insulation is generally sold in 6' lengths.
Consumables
PVC pipe cement and primer
PVC safe pipe joint compound (pipe dope) such as this
Teflon tape
Sand, at least two cups worth (for bending the launcher arms)
2 1/2" pvc caps (for bending launcher arms, not part of gun)
Epoxy for modifying sprinkler valve
Thread locker (Loctite)
Tools & Safety
Saw, for cutting PVC pipe
Heat gun, propane torch, or candle for bending PVC
Drill
3/16" and 7/16" (or 5/8" see the **note in the pressure chamber section) drill bits
Tape measure
Utility knife
Dremel tool, or similar, with a sanding drum
Wrench for 1/4" npt hex nipple
Large adjustable wrench or channel-lock pliers, for tightening the trigger valve
A compressor or pump capable of attaching to a Schrader tire valve and attaining at least 80 psi
Safety glasses
Leather gloves
Image Notes Image Notes
http://www.instructables.com/id/Build-A-Net-Gun/

1. Pressure chamber section.
2. Trigger valve section.
3. Launcher section.
Image Notes
1. 1" orbit 57461 sprinkler valve. This was a model downloaded from the google
3-d library, it doesn't look exactly like the valve.
2. Blow gun.
3. 1/4" NPT male to male coupler.
Step 2: Net Procurement And Math
http://www.instructables.com/id/Build-A-Net-Gun/
1. 2" cap with tire valve inserted.
2. 9" length of 2" PVC pipe.
3. 2" coupler with 2" to 1" bushing in one end, shown with optional pressure
gauge.
4. 1" slip elbow.
5. Length of 1" pipe functions as the pistol grip area. Dry fit until you arrive at a
length that you find suitable. Somewhere between 3" and 6" should be sufficient.
6. 1" slip to 1" MPT elbow.
Image Notes
1. Net holder
2. Launcher arms, tractors slide over and onto these.
3. Threads into trigger valve.
I ordered my net from the Memphis Net & Twine Company. If you have your own favorite gill net vendor, you can probably order an identical item from them. I have NO
financial ties to MN&T other than being a satisfied purchaser of their retail products.
Here is the link to the product page on the MN&T website. Below is the exact info from my order information page, shipping is not included in the price. One pound of this
net (minimum order) will make 7 or possibly 8, 9-1/2 foot square nets.
Sku: 263
Description: 3 in. sq. mesh, 12 ft. deep
Qty: 1lb
Price: $12.65
If you would like to try an alternate net part number please read the Alternate Net Substitution section below.
Optional Net Math Section
You may have noticed that the catalog description lists the net as 12 feet deep while I have claimed it is 9-1/2 feet square, why the difference? Let us first deal with a
hypothetical net that has 3" mesh and is 3 meshes deep. You might think 3 x 3 equals a 9 inch deep net, but that would be incorrect. Visualize the meshes as diamonds
stacked point to point and NOT squares stacked like bricks. Reference Fig 1 and it becomes apparent that the depth of our hypothetical net is nearly 12-3/4 inches. To
extend this example to MN&T sku# 263, 27 x 4.24 equals 114.48 inches, divide by 12 and we get 9.55 feet deep. So where does MN&T get the 12 foot depth figure?
They are building a certain amount of droop, when used in a fishing application the diamonds will be longer vertically than they are wide.
I have included a spreadsheet that will allow you to enter different figures to see what size net you will end up with, and how many nets you will get from a pound of that
particular net. If the spreadsheet returns a zero for waste material, you may want to subtract one net from the total expected. The default numbers in the spreadsheet are
for MN&T sku# 263 272.
Alternate Net Substitution
I will use MN&T catalog and part numbers in this example, but as long as you know the correct variables, any net vendor should work. Using the spreadsheet is
important, if you don't own MS excel, consider downloading OpenOffice. An excellent free MS office replacement that will allow you to view and edit the Net Math
spreadsheet.
Please consult Fig 2 or have the spreadsheet open for this example. The top section of the spreadsheet contains a section called Mesh Count Estimator. This will help
you calculate the mesh count you need to reach a desired net size. In this example I have entered 3.5 (3-1/2" mesh) in the Mesh size cell and 9.5 in the Desired depth
cell. This should closely match the sku #263 net's overall size but with a 3-1/2" mesh instead of 3". The computed result, 23.03 appears in the mesh count cell. As
fractional net meshes don't exist, just round to the closest integer, 23 in this case. Next, we will browse through the MN&T catalog for a 3-1/2" mesh net 23 meshes
deep.
Go to the multifilament net section of the MN&T web catalog, then select #208 twine size and browse through the 3-1/2" mesh part numbers to find a net closest to the 23
mesh count. Part number 272 fits our specification perfectly.

Now enter all the information from the 272 page into the yellow cells on the Enter line of the net properties section of the spreadsheet. The Square depth cell tells us this
net will be 9.43' square. This is also the spacing for the knots of your spreader string in step 9. The Knot cut point shows we need to count 46 knots and then cut between
knot 46 and 47, the Cut length cell tells us knot 46 should fall at 161" on stretched netting. We can also assume that because the overall weight of the 272 net is slightly
less than the 263 net, it should fit fine in the net holder.
I would advise waiting to build the net holder part of the launcher section if you try any radically different mesh, twine, or overall net sizes. Once you have the net
constructed, fold it up and make sure you have the correct size PVC holder.
Image Notes
1. 3" mesh with hypotenuse X.
2. Pythagorean theorem, solving for length of hypotenuse X.
3. Hypotenuse multiplied by number of meshes deep.
4. Result is depth if all meshes are square. In the netgun application they are, as
the net tractors pull equally at all four corners.
File Downloads
Net Math.xls (76 KB)
[NOTE: When saving, if you see .tmp as the file ext, rename it to 'Net Math.xls']
Step 3: Build The Pressure Chamber
The pressure chamber is assembled first. It should be allowed to cure a full 24 hours before applying pressure. PVC pipe assembly is simple and is covered in other
instructables as well as on youtube. A brief refresher on solvent welding PVC pipe. Use in a well ventilated area, make sure both pieces to be assembled are clean and
free of burs, prime both pieces, put glue on both pieces, assemble with a twisting motion and hold for 15 seconds. For brevity's sake, solvent welding will be referred to as
"gluing" PVC. The video shows how all the parts are assembled, make sure you have youtube annotation turned on.
Pressure chamber supplies
1 1" MPT (Male Pipe Thread) to 1" slip street elbow
1 1" elbow
1 2" to 1" reducer bushing
1 2" cap
1 2" coupler
1 foot of 1" pipe
Minimum 9" length of 2" pipe
1 valve stem
PVC primer and cement
Drill and 7/16" bit (or 5/8" if you purchased the larger base valve stem)
optional 1 pressure gauge
Assembly
Drill the correct size hole in the center of the 2" cap. 7/16" for the smaller (.453" base) valve stem, or 5/8" for the larger (.625" base) valve stem. Pull the valve
stem through this hole.
Cut a length of 2" pipe at least 9" long. Keep in mind that the longer it is the more time it will take to fill up if you are using a manual air pump.
Glue the 2" to 1" reducing bushing into the 2" coupler
Glue the 2" cap with tire valve to one end of 2" pipe. Glue the coupler to the other end.
Glue a short piece of 1" pipe into the bushing, glue the 1" slip elbow onto that.
Cut a piece of 1" pipe for the pistol grip, something between 3" and 6" should work. Glue the 1" MPT street elbow to one end of pistol grip pipe.
Glue assembled pistol grip pipe into 1" slip elbow on pressure chamber. Ensure that the threaded fitting aligns with the axis of the pressure chamber and doesn't
point off to the right or left.
Optional: Drill a hole of slightly smaller diameter than the fitting of the air valve, locate the hole 3/4" into the pipe side (NOT the bushing side) of the 2" coupler.
Use the air valve to cut threads into the hole, then thread back in using thread locker on the fitting.
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Image Notes
1. 2" cap with tire valve inserted.
2. 9" length of 2" PVC pipe.
3. 2" coupler with 2" to 1" bushing inserted in one end. Shown with optional pressure gauge installed.
4. 1" slip elbow.
5. 1" slip to 1" MPT elbow. Threads into the inlet of the trigger valve.
6. 1" pipe cut to preferred length. This is the pistol grip area where you will hold the gun while firing.
Step 4: Build The Trigger Valve Assembly
In this step we will modify an Orbit Model 57461 1" jar top sprinkler valve, making it a pneumatically actuated trigger valve. I found this particular model to have a number
of advantages. It is the cheapest 1" valve I've found. The air valve is installed in the center of the cap allowing easy orientation of the trigger. Finally, the "jar top"
construction makes it extremely easy to work on. Here is a link to a page devoted to modifying this exact valve, I left out the safety ball valve in this design. Here is a link
to a visual explanation of how the sprinkler valve works.
Trigger Valve Supplies
1 Orbit Model 57461 1" sprinkler valve
1 Blow gun or similar
1 1/4" NPT pipe/hex nipple, like this
Epoxy
Teflon tape
Wrenches
Dremel or drill
Threadlocker
Assembly
Remove solenoid and bleed screw, they will not be needed Fig 1. Save the solenoid for future diabolical inventions.
Disassemble valve by unscrewing the "jar" ring. Be careful, as under the top is a spring under tension.
Cut, grind, or drill out the center of the top, make sure to leave enough plastic to thread the 1/4" NPT fitting into Fig 2. Grind or cut down the lip of material around
the center hole to the level of the ribs Figs 3 & 4. This will allow you to get the fitting deep and tight.
Use the 1/4" NPT fitting as a tap for cutting threads into the hole you just made, try to keep it as perpendicular as possible Fig 5.
Once you have the threads cut, put Teflon tape on one end of the fitting and thread that into the blow gun Fig 6. Apply some thread locker to the other end of the
fitting and tighten the whole assembly into the valve top.
You are now ready to epoxy three places. A little dab in the bleed screw hole in the top, a little dab in the bleed hole at the valve outlet, and a good bit of epoxy
around bottom and top of the brass fitting Figs 7 & 8. Try and leave the wrench flats of the fitting exposed and epoxy free in case you need to remove the blow
gun at some point.
Let the epoxy dry and then reassemble valve. The lever side of the valve should be underneath the outlet of the valve. Make the securing ring is as tight as
possible.
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Image Notes
1. 1" orbit 57461 sprinkler valve. This was a model downloaded from the google
3-d library, it doesn't look exactly like the valve, please see the pictures.
2. Blow gun.
3. 1/4" NPT pipe/hex nipple. One end threaded into blow gun, the other into top of
sprinkler valve.
Image Notes
1. Drill out just this inner section, the remaining hole in the top is just the right size
for a 1/4" NPT fitting.
Image Notes Image Notes
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Image Notes
1. This is the solenoid, unscrew and save for your junk bin.
2. This is the bleed screw, unscrew and discard.
3. "Jar ring" unscrew this to disassemble valve. There is a spring underneath,
careful not to let it fly out!
Image Notes
1. This is the area you want to grind down.

1. This is what the valve top should look like when you are finished. 1. Use 1/4" NPT fitting as a tap to cut threads into the valve top.
Image Notes
1. Wrap one end of the fitting in Teflon tape and thread it into the blow gun. Put
some thread locker on the exposed fittings threads, and thread the whole blow
gun assembly into the valve top.
Image Notes
1. Pour the most amount of epoxy here. Make sure you don't get it into the fitting!
2. Epoxy the bottom side of bleed screw hole as well.
Step 5: Assemble And Test Valve and Pressure Chamber
Image Notes
1. Epoxy here.
2. Epoxy here.
3. Epoxy around brass fitting on both top and bottom. Try and leave wrench
flats clear of epoxy.
Once your pressure chamber has cured for 24 hours, and your trigger valve has cured long enough for the epoxy to reach full strength, you are ready to assemble and
test the trigger valve and pressure chamber.
Supplies
Assembled pressure chamber from step 3
Assembled trigger valve from step 4
PVC pipe joint compound (pipe dope) such as this
Source of pressurized air
Wrench or channel lock pliers
optional 5 gallon bucket filled with water
Assembly
Thread your trigger valve onto the pressure chamber for a test fit. The arrows on the side of the valve point in the direction of the airflow, they should be pointing
away from the pressure chamber. The goal is to get the blow gun situated vertically in front of the pistol grip to act as a trigger. Use the channel lock pliers or
adjustable wrench to get the trigger valve as tight as possible. If the sprinkler valve bottoms out before the blow gun trigger is vertical, you can file off small
amounts of plastic from the end of the threaded street elbow until it fits perfect.
Fill the chamber to 80 psi. Aim in a safe direction and briskly pull the trigger, you should get a loud POP and feel a bit of recoil. Here is a great troubleshooting
guide if your valve does anything other than go bang.
Once you have a successful test, remove the trigger valve. Apply the pipe joint compound to the street elbow threads and tighten down the valve once more.
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Optional: perform a leak test. Pressurize your chamber to 80 psi. Fill a 5 gallon bucket with water and dip the assembly, look for any bubbles. Tighten and add
pipe joint compound to areas with leaks. If the PVC joints are leaking on the pressure chamber, you can apply a vacuum and suck super glue into the voids.
Image Notes
1. Assembled pressure chamber and trigger valve. Ready for function and leak testing.
Step 6: Bend Launcher Arms
In this step we will build a bending jig, and use it to bend four launcher arms to a specific angle. Make sure annotations are turned on when viewing the video.
Launcher arm supplies
4 13" lengths of 1/2" pipe
2 1/2" PVC caps DO NOT PRIME OR GLUE THEM
Sand, at least two cups worth
Heat gun, propane torch or candle
Wood scrap and 3 2" screws to make bending jig
Leather gloves
Assembly
Choose a launcher tube angle. A 17 or 19 degree angle will give you longer range but you may need the high performance tractors. A 21 or 23 degree angle will
give you quicker opening shorter range netting, a safer bet if you are going to use soda bottle tractors. Choose and print out one of the PDF templates below.
They should be printed in landscape mode on 8 1/2" by 11" paper at 100% scale.
Build bending jig. My example bending jig is built on a scrap of 2x4 wood. Hold the template to the surface and put a screw in the pivot position Fig 1. Hold one of
the arms against the pivot screw and sink screw #2 using the edge of the pipe as a guide Fig 2. Again, with the pipe held against the pivot screw, sink screw #3
using the pipe edge as a guide Fig 3.
Cut four 13" lengths of 1/2" pipe, these are the launcher arms. Measure and mark, with permanent marker, 3" in from one end of each arm. This mark, the pivot
mark, will indicate where to heat the pipe for bending, and indicate the point to line up with the pivot screw of the bending jig.
Bend the launcher arms. Tap in place, but DO NOT GLUE, a 1/2" cap on end of the arm. Fill pipe with sand, and tamp to get as tightly packed as possible Fig 4.
Fill the second 1/2" cap half full with sand and tap on the open end of the arm. The sand keeps the pipe from kinking. With both caps on the pipe the sand
shouldn't slosh when shaken, if it does, add more sand. Put on leather gloves and heat arm as locally as possible on the pivot mark. Rotate the pipe rapidly for
even heating and to prevent blistering the pipe. The arm is ready for bending when it will sag under its own weight held horizontally. Align pivot mark with pivot
screw, the remaining short length should be captured by screw #2, immediately bend longer length of pipe over and lodge against screw #3. Allow to cool on the
jig, if PVC is removed while it is still warm it will begin to straighten and lose the correct angle. Once PVC is room temp, remove from jig, remove both caps, and
pour out the sand. The heating can also be accomplished with a candle, have a look at robert's instructable step #3. Both tk4717 and ome33 had good results
with the candle technique.
Repeat for the remaining three arms.
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Image Notes
1. Model of the bending jig.
Image Notes
1. Sink screw #2 using the edge of 1/2" pipe as a guide.
Image Notes
1. PVC pipe filled with sand. Fill the cap about half full as well. The tube should be
packed so tightly that the sand doesn't "slosh" around inside.
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Image Notes
1. Sink the pivot screw.
Image Notes
1. Sink screw #3, again use the edge of 1/2" pipe as a guide.

File Downloads
17 degree.pdf ((612x792) 201 KB)
[NOTE: When saving, if you see .tmp as the file ext, rename it to '17 degree.pdf']
19 degree.pdf ((612x792) 172 KB)
[NOTE: When saving, if you see .tmp as the file ext, rename it to '19 degree.pdf']
21 degree.pdf ((612x792) 210 KB)
[NOTE: When saving, if you see .tmp as the file ext, rename it to '21 degree.pdf']
23 degree.pdf ((612x792) 216 KB)
[NOTE: When saving, if you see .tmp as the file ext, rename it to '23 degree.pdf']
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.
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Image Notes
1. Correctly aligned street elbow, relative to launcher arm. All four should look
like this.
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Image Notes
1. Launcher arms from step 6
2. 1/2" cross
3. Nickel with 3/16" hole in the center.
4. two 1/2" tees
5. four 1/2" street elbows
6. ** 1" MPT to 3/4" slip, 3/4" to 1/2" bushing.
7. 9" length of 1-1/2" pipe.
8. 1-1/2" coupler
9. ** 1-1/2" to 3/4" bushing, 3/4" bushing to 1/2" bushing.
10. four 1 1/2" lengths of 1/2" pipe, one for each side of the cross. These are the
coupler joiners.
Image Notes
1. Incorrectly aligned street elbow.

Image Notes
1. Incorrectly aligned street elbow.
Step 8: Assemble Tractors
Tractors are what slip on to the launcher arms and are propelled with compressed air to pull the net outward. You can build two kinds of tractors. The simplest are just
four empty soda bottles. They must be bottles that were used for a carbonated beverage as they were designed to withstand pressure. Other bottles, especially water
bottles, are much flimsier and likely to burst. The bottles can be filled with a little bit of hot glue, silicon adhesive, or wax to give them a bit more momentum. The soda
bottle tractors are free, nearly indestructible, but suffer slightly shorter range. The high performance tractors are more efficient, due to lower internal volume, so have
greater range. They are a bit more fragile, SDR-21 (Class 200) PVC pipe may be hard to locate, and they take a little more time to fabricate.
Tractor supplies
4 per net 16 or 20oz carbonated soda bottles
Hot glue/silicone sealant/wax to pour in bottles to add weight
Optional additional items needed for high performance net tractors
4 per net 3/4" couplers
4 per net 3/4" caps
4 per net 8" lengths of SDR-21 (Class 200) 3/4" thinwall PVC note: regular 3/4" SCH-40 will NOT work!
4 per net 12" lengths of non-adhesive 1" ID foam pipe insulation
Super glue
Utility knife
Dremel with sanding drum
Assembly
When selecting soda bottles I would advise digging through a recycle bin with a launcher arm in hand. You want a bottle that slips over the launcher arm, and,
ideally, will not slide off under its own weight. Make sure the bottles are identical volume, don't mix in a 16 oz bottle with three 20 oz.
For the soda bottle tractors, there is very little assembly. You may want to test your net gun with unweighted bottles, as you can always add weight later. Use a
scale, or melt/pour identical pre-measured amounts into each bottle. I don't recommend adding more than 40 grams to each bottle.
For the high performance tractors, begin by cutting the necks off of the 4 soda bottles Fig 1. Use the Dremel tool to sand down the threads Fig 2 so the neck can
be pushed into one end of a 3/4" coupler. Once it fits snugly, super glue in place Fig 3.
Take the 8" lengths of 3/4" SDR-21 (Class 200) and glue the soda neck couplers on one end and a 3/4" cap on the other Fig 4.
Cut four 12" lengths of pipe insulation. These will be slipped over the net tractors leaving 2-3 inches of cushion at the end . This will protect the tractor from
shattering if it hits the ground. It will also minimize damage if the tractor accidentally hits something valuable, like a car, plasma TV, or a cranium. Wait until the
tractors are tied to the net (next step) before putting on the insulation.
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Image Notes
1. 3/4" coupler with soda bottle neck in one end.
2. 3/4" SDR-21(Class 200) thin wall PVC. SCH-40 will NOT work as it won't slip
over 1/2" PVC. This is the ONLY component that utilizes SDR-21.
3. 3/4" PVC cap,
4. High performance net tractor.
Image Notes
1. Grind the threads off the bottle top so it will fit snugly in the 3/4" coupler. Use a
scrap of 1/2" PVC to hold the cap.
Image Notes
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Image Notes
1. Cut the neck off the soda bottle
Image Notes
1. Super glue the neck into one end of the 3/4" coupler.

1. 8" length of SDR-21 3/4" pipe.
2. 3/4" cap.
3. 3/4" coupler with bottle neck in one end.
4. Completed tractor. You need four per net.
Step 9: Assemble Net
A single net will be cut from the large net you ordered. We will build a net spreader, a string that runs the perimeter of the net and pulls it evenly into a square. The
tractors are tied to each corner, through a loop in the spreader string, and a loop in the corner mesh of the net. This step involves a little knot work, I use the overhand
loop, the bowline, and the double fisherman's bend.
All of the dimensions in this step relate to MN&T sku# 263, if you use a different number you will have to change the following three dimensions.
Substitute the Knot cut point value from the net math spreadsheet instead of knot 54.
Substitute the Cut length value from the net math spreadsheet for the 162" value.
Substitute the Square depth value from the net math spreadsheet as the overhand knot spacing for the net spreader string, instead of 9.55'.
Net supplies
4 tractors from step 8
1lb Memphis Net and Twine sku# 263
OR a substitute net computed using the net math spreadsheet in step 2
At least 50' of nylon mason's twine (#15 or smaller), kite string, or some other thin durable rope. This will be the spreader string
Utility knife
4 zip ties
Assembly
You will receive a pound of net in a plastic bag. The net is pulled taught and wound into the bag like a rope. Find the free end and count off 54 knots and then cut
between knots 54 and 55 Fig 1. The 54th knot should land at 162" Fig 2.
Take your spreader string and measure 5' and tie an overhand loop. Tie three more overhand loops every 9 foot 6 inches. Leave another 5' of string after the
fourth knot and cut. You should end up with 4 overhand loops evenly spaced with 5' of free string at either end Fig 3.
Spread your net out in an area where it can lay flat and as square as possible. Tie an overhand loop in the corner of each corner mesh of the net.
Weave the spreader string through the rim meshes of the net Fig 4. A spreader string overhand loop should line up with each net corner overhand loop Fig 5. The
5 foot 'tails' you left on the spreader string should meet in the middle of the remaining side. Measure a length of 9' 6" on this side and tie a double fisherman's
bend in the middle Fig 6, cut off excess string.
Cut four 2' lengths of string, these will be the tractor strings. Tie one end of the tractor string by making a bowline that passes through both the spreader loop and
mesh loop Fig 7. Tie a second bowline at the other end of the tractor string, try and end up with 16" from bowline to bowline. Zip tie the free bowline to the bottle
neck or the PVC tractor body Fig 8. You can try tying a knot here but I have yet to find one that holds well.
If you built the high performance tractors, put the pipe insulation on now. Slide the insulation until it completely covers the tractor Fig 9. Make sure to leave 2-3" of
foam at the cap end of each tractor to act as a shock absorber.
Image Notes
1. Knot 54 lands at 162"
2. Cut here, in between knots 54 and 55.
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Image Notes
1. Severed between knot 54 and 55.

Image Notes
1. Overhand loop tied in corner of net.
2. Overhand loop tied in the spreader string.
Image Notes
1. Tractor string bowline tied through both the spreader and net overhand loops.
One at each corner, four total.
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Image Notes
1. Weave spreader string in an over under fashion through rim of net.
Image Notes
1. The double fishermans bend, tied at the ends of the spreader string "tails."
Should fall in the center of one side of the net.
Image Notes
1. Tractor string bowline, zip tied to tractor.

Image Notes
1. 12" length of 1" ID pipe insulation slipped over tractor.
Step 10: Loading And Firing The Netgun
Now for the fun part. Please be safe in this step. If the launcher arms aren't glued, there is a chance they will fly off during firing, so make sure any spectators are behind
you. Only load the net gun when there is NO pressure in the chamber. It is helpful to have an assistant when laying out and untangling the net.
Firing and reloading supplies
Assembled netgun
Assembled net
Open area, preferably outside
Compressed air source
Lay net on ground in a square, pick a clean area, as getting leaves or other debris in the net will keep it from deploying correctly. Pick two tractors, hold them
together, these are the tops. Walk the tops across the net so they are in between the other two tractors, these outside two are now the bottoms. Move the tractors
together so they are in a row touching sides.
Starting at the base of the tractors, pull the net into a rope-like tube. Begin at the tip of this tube (farthest from the tractors), grab a 6-8" handful of net and fold
back and forth in a zig zag fashion until you are up to the tractor strings. Do NOT keep folding in the same direction, rolling the net will keep it from deploying
correctly.
At the end of the zig zag fold you will end up with an 8 inch, or so, bundle of net. Smooth this bundle out, and insert into the net holder, it will fit snugly.
Remember your top and bottom tractor order. Working left to right the first tractor slips on the bottom left launcher arm, second on the top left, third on the top
right, and the fourth on the lower right.
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Pressurize net gun to 80psi. You should have a at least 30 feet of downrange space free of anything that the net might get entangled in. Keep any spectators
behind you in case an unglued launcher arm flies off.
Aim net gun. Visualize yourself at the point of a skewed four sided pyramid Fig 1. The two lower launcher arms fire horizontally and outward, the upper pull up
and out, your prey will be ensnared in the base of the pyramid. Pull the trigger. If everything goes well the net will be pulled into a square somewhere between 12'
and 25' feet in front of you. Consult the troubleshooting tips (below) if net doesn't deploy as desired.
Once you are satisfied with the net deployment, glue your launcher arms in place. Make alignment marks with indelible marker or tape before disassembly, you
will then have good alignment references when you glue it back together.
If you decide to paint your net gun, do not paint the launcher arms. Even a thin layer of paint will cause the tractors to stick.
Troubleshooting
Net deployed in a horizontal rectangle, not square. Add more up angle to the top launcher arms.
Net deployed in a vertical rectangle, not square. Reduce the up angle of the top launcher arms.
Net deployed like a big X, not a square. Caused by putting a tractor on the incorrect arm during the loading sequence. Make absolutely sure you keep the tractors
in the correct order, put marks on them if it helps.
Net never really opened up at all. Caused by debris in the net , wet net, or poor folding technique. May also be caused by low pressure due to air leaking out
while waiting to fire.
launcher arm flew off. Many possible causes.
Make sure the launcher arms are firmly tapped into the tees.
Too much weight in soda bottle tractor(s) causing excessive back pressure. Try starting with empty bottles.
Sticking tractor(s), make sure the tractors can move freely on the launcher arms. If one or more seem to be stuck, correct problem by replacing tractor or defective
launcher arm.
Too high pressure, start low (70-80psi) and then work up.
http://www.instructables.com/id/Build-A-Net-Gun/

Step 11: Et cetera
Thanks for all the positive responses so far. I will post updates to the build and attachments here. I came up with the safety after negligently discharging a net while filling
the pressure chamber. It is so easy to make, every responsible net gun owner should have one. I developed the tennis ball attachment while working on an older net gun
design that had a 2" net holder, it is a lot of fun for the $3 it costs to make.
Mechanical Trigger Safety
A very simple mechanical safety that will prevent the net gun from firing in the event the trigger is unintentionally actuated.
Supplies
Scrap 1/2" pvc pipe
Small rubber band
Assembly
Cut a short length of 1/2" pipe, probably between 1/4" and 3/8", it will depend on the specifics of the blow gun. It needs to fit under the blow gun handle and be
thick enough to prevent the handle from depressing the valve underneath. You made need to cut a wedge out of one side of the ring to allow it to slip under the
handle.
Loop rubber band around one end of ring, and through itself. Take the free loop of the rubber band and slide onto the body of the blow gun valve.
To put ON SAFE, slide ring around brass valve underneath lever Fig 1. To take OFF SAFE, slide ring down and out of the way of valve and lever Fig 2.
Tennis Ball Launcher
The inside diameter of a 2" PVC coupler fits a tennis ball perfectly. If you own a ball chasing canine, this will forever associate the bang of compressed air with the joy of
the chase.
http://www.instructables.com/id/Build-A-Net-Gun/

Supplies
1 1" slip to 1" MPT adapter
1 2" coupler
1 2" to 1" reducing bushing
2" length of 1" PVC pipe (scrap from pressure chamber assembly)
At least one tennis ball
PVC primer and cement
Assembly
updated
Fig 3 is a view of all the components needed for this attachment.
Glue the bushing into the coupler.
Glue the 1" pipe into the slip end of the of the 1" MPT adapter.
Glue the exposed 1" pipe from the MPT adapter into the bushing. Let set for 24 hours.
Unscrew and remove the net attachment, and thread on the tennis ball attachment. With tennis ball on the ground push the launcher attachment over the tennis
ball until it is firmly seated Fig 4.
Pressurize and fire. Repeat as necessary. If you have a slobbery dog Fig 5 you will appreciate not having to touch the drool covered ball.
Image Notes
1. On safe position. Small ring of PVC is preventing the blow gun lever from
depressing the release valve.
2. Small rubber band, looped around body of blow gun.
Image Notes
1. 2" PVC coupler.
2. 2" to 1" slip reducing bushing
3. 2" length of 1" PVC pipe.
4. 1" slip to 1" MPT adapter.
http://www.instructables.com/id/Build-A-Net-Gun/
Image Notes
1. Off safe. Blow gun is free to operate normally.
2. This particular blow gun needed a small wedge cut from the ring. The other
two I built did not. It depends on your particular model.
Image Notes
1. Tennis ball launching attachment. Loaded and ready to go.

Image Notes
1. Slobbery ball chaser. AKA Colby.
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http://www.instructables.com/id/Build-A-Net-Gun/
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50 comments Add Comment view all 577 comments
mloveridge says: Mar 22, 2011. 2:08 AM REPLY
This. This is just awesome.
tdking3523 says: Mar 15, 2011. 6:58 PM REPLY
I'm only a 14 year old kid with a few friends, do you think this will be a difficult thing to build on our own? cause I don't want to buy the parts and not be able
to make it.
Thanks!
bowmaster says: Feb 25, 2011. 1:19 PM REPLY
This was linked to by Cracked.com: http://www.cracked.com/article_19038_the-7-most-stupidly-overpowered-hunting-weapons.html
aleceatsfood says: Feb 15, 2011. 5:27 PM REPLY
hey this is cool!
Iwanna b says: Jan 27, 2011. 7:46 PM REPLY
Your link to a blowgun sent me to a website, but there are many choices there, which one is the one I should buy?
crispyjones says: Jan 27, 2011. 8:51 PM REPLY
I changed the link to go where it used to, thanks for catching that. Unfortunately, it looks like that model isn't available mail order from Harbor Freight. It
is a very common style of blow gun, I've seen it at auto parts stores, hardware stores, even Walmart.

Nykus79 says: Oct 9, 2009. 7:58 AM REPLY
Look like I has found weapon non-leathel to use on police who chase me after i did something break laws. it should slow them down
ToddisI says: Jan 22, 2011. 9:38 AM REPLY
lol
diedhert says: Jan 15, 2011. 11:55 AM REPLY
I studied these instructions. I have a question about step 8.
What is the purpose of the soda neck back couplers of the tractor?
Wouldn't the tractor fullfill without them (just cap + 8" PVC pipe) ?
Or is it just because it is easier to put them on the launchers (due to the soda neck)?
Thanks in advance.
crispyjones says: Jan 15, 2011. 1:27 PM REPLY
It just seals the tractor really well, the more air that is captured in the tractor means more energy transfered when they are launched. It's possible it would
work without soda bottle necks, but they would fall off really easy and probably not go as far.
jlissy1987 says: Jan 14, 2011. 12:56 PM REPLY
I tried building this, but we can't get the soda bottles to fly off the tractors, they hardly make it off of the tractors. We've checked it for leaks several times,
can't find any it seems to hold pressure just fine. As far as I can tell, all the air is going out the bottom of the blow gun instead of into the tractors. Are we
supposed to epoxy the top of the blow gun so air can't go out of the blow gun? I don't think we are, but I'm not entirely sure.
crispyjones says: Jan 14, 2011. 6:30 PM REPLY
Air should only come out the blow gun when you pull the trigger. If air rushes out without pulling the trigger you have a defective blow gun. Only epoxy
around the base where it is threaded into the valve. Make sure you have the sprinkler valve on in the right direction, there is an arrow on the side of the
housing, it should point in the direction of the airflow, away from the pressure chamber. Check for leaks in a bucket without the launcher arms screwed
on, they are much easier to spot. Keep posting and we'll figure it out.
the_doctor says: Oct 6, 2010. 6:18 AM REPLY
I used copper pipes for my pneumatic cannon
sonofspikerr says: Oct 15, 2010. 4:47 PM REPLY
doctor who=best show ever! Are you american or european?
the_doctor says: Jan 12, 2011. 7:31 PM REPLY
enlglish
Freesoil says: Jan 11, 2011. 8:48 AM REPLY
do you need the trigger system to use this gun? or is it more for just easier shooting?
MeGravity says: Jan 10, 2011. 8:05 AM REPLY
What's the used CAD package... looks lovely. I have to permit that I didn't read through the whole article so far ;-)
Thx
jrgabbardo says: Jan 8, 2011. 6:11 AM REPLY
Have you thought in the possibility of adapting some sort of hand pump to fill the air reservoir and make the net gun portable? Of course an ordinary pump to
fill bike tires would not do the job but why not try to use or even build another kind of powerful hand pump?
Best regards!
kameronk92 says: Dec 17, 2010. 2:31 PM REPLY
How do you pressurize the gun, dude?
quetip1 says: Dec 12, 2010. 8:32 AM REPLY
sooo... I want to build one of these but I want it to look like a rifle and have the net be 6-feet-by-5-feet. do you think it would be possible to fit this in a nerf gun
frame or atleast a moddified one. thanks for any ideas on the subject
http://www.instructables.com/id/Build-A-Net-Gun/

mikeysmachines says: Dec 4, 2010. 8:40 PM REPLY
i want to build one of these to shoot it in my house is that possible, can any part of the net harm anything in my room like my lcd and can i customize the
lengths of the rope so its not to big flying across the room (I want it to be able to catch my friend) thanks
crispyjones says: Dec 5, 2010. 8:47 AM REPLY
I would have to warn against doing this without changing some significant things. The net itself is 9.5 feet per side, the tractors and strings add another
foot, at least, in each direction. If you hold the net gun at chest level the top of the net can be somewhere around 15' above the ground and almost 12'
across, you would need a really big room for this to work. As soon as any tractor hits anything, the whole net will stall. The only time I fired this inside, I
was in an enormous garage and it was my first net gun that used a smaller net.
I think you will have to use a much smaller net (and figure all the corresponding net math), thicker foam on the tractors, possibly lighter or smaller
tractors, and maybe reduce the pressure. I am pretty sure the net gun could harm lots of things in your room, including the LCD.
It is probably easier to just ambush your friends outside.
baughmanmark says: Nov 18, 2010. 10:29 AM REPLY
The link that you give for the net, is that a pre-made net because it looks like it.
crispyjones says: Nov 18, 2010. 11:45 AM REPLY
The net itself is pre-made, but you can't just pull it out of the box and put it in the net gun. You get a long length of net, but you still have to cut it to the
correct length, add the spreader string, and attach the tractors.
baughmanmark says: Nov 10, 2010. 5:34 PM REPLY
I did everything you said to do with the Trigger Valve System but when I put air inside the chamber is leaks out of from that hooks to the tennis ball
attachment and also when I press the blow gun it does nothing. What am I doing wrong?
baughmanmark says: Nov 10, 2010. 7:08 PM REPLY
Never mind about my question. I put the wrong end towards the pressure chamber (the arrows were pointing toword the pressure chamber).
crispyjones says: Nov 10, 2010. 6:25 PM REPLY
First make sure the flow arrow on the valve is pointing in the direction of the air flow, back of the arrow towards tank, pointy end towards outlet. Next, put
some air in the pressure chamber and see exactly where it is leaking from. If it is leaking out of the small "nipple" in the center of the outlet (step 4, fig 7)
than you need to seal that off with some more epoxy. If it is leaking out of the outlet (and not the nipple) than it is likely the diaphragm is not seating. This
can happen if PVC chips get stuck in there, just disassemble the valve and make sure the seating surface is clean.
I went through some similar issues earlier this link *might* (direct link to comments seems flakey) take you there. If not, go back to the May 31, 2009
comment string in Step 5.
If none of this helps, post the things you tried and I will see what I can do. Good luck.
SP Tutorials says: Nov 9, 2010. 1:21 PM REPLY
Oh my god this is freaking amazing. I am totally building this. Btw check out my tutorials. I have one so far bit I am working on a new invention of mine.
PIZZA TACOS!!!!!!!! (:
rhoddity says: Oct 28, 2010. 11:45 AM REPLY
Love the trigger mechanism (with a safety system and everything)
I think this takes the cake for coolest functional PVC based ible I've ever seen, full-stop!
xboxdude says: Oct 27, 2010. 6:27 PM REPLY
this was very cool. my dad and i made it together
bigtreehouse says: Oct 10, 2010. 4:43 PM REPLY
You da man. I have wanted to do just this for years. Next work on the Bathook... the grapling hook launcher.
matt says: Oct 10, 2010. 6:12 AM REPLY
This is an excellent instructable. Very nice work, have fun!
Munchys says: Oct 7, 2010. 7:19 PM REPLY
this is kinda hard to find the parts
http://www.instructables.com/id/Build-A-Net-Gun/

clutch00 says: Oct 3, 2010. 9:39 PM REPLY
ok i understand everything exept the blow gun and the sprinkler valve seems it would be easyer to use a straight brass ball valve???? but im going to buy
the stuff in the mourning
Screamo says: Sep 26, 2010. 7:11 PM REPLY
Dude thats awesome go catch some bears :D
j4lmmfwcl says: Aug 21, 2010. 7:14 PM REPLY
im almoast done with my net gun but i cant figure out the size of the net.
crispyjones says: Aug 24, 2010. 12:22 AM REPLY
You're not giving me much info. Did you buy a different net size other than #263?
Ukrobotman says: Aug 18, 2010. 12:30 PM REPLY
Hi I am based in the Uk and am planning to build one of your guns here using parts available in our local stores which differ from yours. I will keep you guys
posted as to how I get on. I was at Maker Faire in San fransisco in May and a cool Steampunk guy had built his own net launcher. I know cos he shot it at
me! I didn't get to investigate how he had made his, it was more compact than your design. Do you or does anyone else know any more about the guy and
his machine.? Regards Steve in London
crispyjones says: Aug 18, 2010. 7:50 PM REPLY
I was at Maker Faire too, great time. I saw the net gun you are talking about, the group was the League of Steam I believe. There are a few videos on
youtube, and some picture on flickr. It looks like it is sprinkler valve based, he kept the electric solenoid. I really don't know what he used to launch the
tractors. Good luck on your UK build, I am interested to hear how it turns out.
ToolTech says: Jul 26, 2010. 9:53 PM REPLY
I know this has more than likely previously been questioned, but is the thinwall PVC necessary? I have plenty of 3/8" laying around but as with others I have
had troubles finding thinwall. Will performance severely lack if I use the regular PVC?
crispyjones says: Jul 26, 2010. 10:56 PM REPLY
I am assuming you meant 3/4" PVC not 3/8". Regular 3/4" PVC will not actually fit over 1/2" PVC, that was why I recommend using the thinwall.
Additionally, the 3/4" couplers are very close in size to the bottle necks. The next closest sch40 PVC that would fit would be 1". I think it might be a tight
squeeze fitting the bottle neck into one end of 1". If you do get 1" tractors working, let us know in the comments.
Danno420 says: Aug 15, 2010. 11:46 AM REPLY
I used 1" sch 40 tractors with 1" caps on the ends. The bottle necks of certain bottles fit perfectly. I added rubber cement to help keep em in. I used
black plastic, 1/4" hole bird netting I bought at Home Depot (comes in 14' x 14'). The tractor launcher arms are set at 10 deg and the net at the
moment is 7 x 7 foot. I used a little electrical tape to hold the net to the tractors. It fires great. We have fired it 50 times or more and the net is still not
ripped or coming off of tractors. I am still going to buy the recommended net though at some point. Took about 3 hours to get all my parts together at
home depot, but me and my buddy assembled nearly the whole gun in the isle just to be sure we weren't going to need to make a second trip. The
funny thing is we used all 2 foot pieces for everything including all couplings and the gun was about 14 feet long on the ground in the isle of Home
Depot. LOL ....Then we knew we had everything correct (except for tooo many 2 foot pieces we don't need) but then we put back all the extras. The
only thing we deviated from on this project to keep the cost down a hair, was the trigger. Instead we just bought a 1" ball valve and mounted it with
the T-handle on the left side of barrel in the exact spot the sprinkler valve would have gone. It works great. If we wanted to add the sprinkler valve
later we can just unscrew the ball valve and screw in the sprinkler valve, but I don;t see the need. Also we made the pressure chamber with 2" pipe
and about 16" long. We are going to be replacing the front net holding tube with 4" pipe. We currently have the center net tube capped off so we are
not using any air to push it out and it still works great with extra power for the tractors. We have come to find the 4" tube will hold more net and
looser. I have left a easily removal 1/2" cap on the center tube though so if I choose to use it I just pry off the cap. I can cap the tractors and uncap
the center tube, load it with backing and some fish gravel and now I have a shotgun too. Thanks for all the instructions. Everything went without a
hitch.
crispyjones says: Aug 16, 2010. 3:47 PM REPLY
That's great that you got bird netting to work. I can definitely see using a larger net holder, I remember that stuff being pretty stiff. I would love to
see a photo or video of it in action. I am also interested in what kind of range you get out of a 10 degree launcher angle. Thanks for posting!
ToolTech says: Jul 27, 2010. 11:30 AM REPLY
(My bad spelling error) Thanks alot, I'll mess around with it a bit. Im using a air chamber from a previous potato gun with a one inch ball valve. It is
two large fire extinguishers linked with galvanized steel elbows. I need to adapt your net design to one inch at the open one inch ball valve. My
design has a pressure gauge built in as well. However I still need a net before I can test the setup.
Kantor says: Aug 13, 2010. 7:14 PM REPLY
would heavy duty liquid nails be a good epoxy??
http://www.instructables.com/id/Build-A-Net-Gun/

crispyjones says: Aug 13, 2010. 9:02 PM REPLY
I doubt it. I know they sell some different versions of the product, but the ones I've seen don't look suitable.
Kantor says: Aug 13, 2010. 9:53 PM REPLY
so what would work?
crispyjones says: Aug 14, 2010. 3:30 PM REPLY
Use the two part epoxy that comes in the double syringe type applicator. It is sold by many manufacturers, I have used different brands with
similar results. I think I used Loctite brand last time, but I am not 100% sure.
Kantor says: Aug 14, 2010. 11:39 PM REPLY
i just so happen to have about half a syringe of that stuff laying around,thanks for the help
jpa234 says: Jul 18, 2010. 11:31 PM REPLY
do you think you could shrink it down somewhat and make parts of it fold/unfold then mount it on your arm.
view all 577 comments
http://www.instructables.com/id/Build-A-Net-Gun/