CSV19 Pneumatic Antenna Launcher Instructions

This air-powered Tennis Ball launcher is designed to launch tennis balls over trees towing fishing line. The fishing line is used to pull up nylon twine and wire antennas, or heavier line and larger antennas. This design is 19 inches long and optimized to fit in a Rubbermaid (tm) plastic tote box so that it may be easily deployed to the field. These launchers are used by Amateur Radio groups doing Emergency Service and other portable work, as well as installing antennas in backyard trees.


Document Notes

Version 2.10  5/4/2008

Building the CSV19 (or CSV17) Compact Antenna Launcher

There are several choices available to the builder wanting to build the CSV19 or a variation of this antenna launcher. Collect the parts, or purchase a kit of parts already prepared.

The builder wishing to do it yourself will find instructions below on doing that. If you have purchased a kit you can skip over the detailed procurement and preparation instructions to the Kit Assembly instructions below.

The CSV17 Launcher differs slightly from the CSV19 model. The overall length is reduced to 17 inches, so the barrel and chamber are shorter. The chamber is also constructed from 3" pipe instead of 4" pipe, so the chamber endcaps are also 3". This reduces the weight and bulk considerably. It does require slightly higher pressures to operate, but the smaller volume pumps up very quickly. The CSV17 is well suited to 12 gram CO₂ cartridge usage. The maximum height reached by the CSV17 is over 150 feet, whereas the CSV19 can reach 200 feet under good conditions.

CSV19 Antenna Launcher Standard Materials List

2.5" by 16" schedule 40 (or SDR21) PVC pipe (barrel)
2.5" PVC end cap (barrel end)
1.25" 90 degree elbow, 2 each. It is best if one end of one of the elbows is round, smooth, and free of lettering, texture, and casting bumps. This will fit best into the hole bored into the barrel endcap.
1.25" dia by 2.5" pvc pipe (to join the elbows)
1" to 1.25" PVC bushing
1" by 6" long PVC pipe (various joiners)
1" coupler (to cut strenghtening ring from for endcap to pipe adapter)
4" schedule 40 PVC end cap, 2 each (pressure chamber)
4" dia by 8" long PVC schedule 40 pipe (pressure chamber) (since the pressure chamber is larger than it needs to be this pipe could be reduced to 6 or 7 inches in length with minimal effect on performance). Even 4 to 5 inches should work fine, albeit a little higher pressure will be required to reach a particular height, and the maximum achieveable height will be slightly reduced.
Schrader valve, 1/8 NPT, short (ACE hardware, www.McMaster.com #8063K33)
Pressure gauge, 0-100 psi, approx 1" dia, 1/8 NPT, www.McMaster.com #38105K32
Sprinkler valve, 1", Rainbird 100-DV, solvent cement sockets (www.sprinklerwarehouse.com #100dvss)
1/4 NPT brass street elbow, (Yardbird, Home Depot 'Watts A-739', very short machined type preferred rather than the longer cast type)
Air Duster, 1/4 NPT, www.HarborFreight.com #3962 thumb type duster (this unit requires a 1/4 NPT short adapter pipe). Other types of air air dusters or blowguns should also work as long as they have adequate airflow and fit mechanically - NOTE - the Harbor Freight air dusters 42939 and 42940 purchased after about 6/2007 have reduced flow and produce underpowered launchers. Use a higher flow air trigger for better performance.
Barrel-Chamber Spacer w/ double sticky foam tape on both ends
Large Cable Tie
1.5" to 1/2" PVC bushing (loading ram end)
1/2" dia x 18" schedule 40 PVC pipe (loading ram shaft)
80 PSI Maximum Operating Pressure" label (I use a Brother P-touch labelmaker)
2.5" coupler (fishing reel attachment)
two stainless steel hose clamps, 3.5" (reel attachment)
1.5" by 1/2" piece of double-sticky foam mounting tape (reel attachment)
Other required equipment for use - fishing reel, line, tennis balls, Rubbermaid 10 gallon tote for carrying case, pump or other source of pressure, nylon twine to pull up with the fishing line, antennas, etc.

Finding Parts for the CSV19 Antenna Launcher

CSV19 Antenna Launcher Parts Kits

I have pre-made parts kits for the CSV19 antenna launcher. I keep an inventory of parts on hand, though some machining may remain before a kit can be shipped.

The two bored endcaps are the most difficult parts to make for this launcher. Drilling and tapping the valve is a bit difficult as well, and requires a different size drill and tap than the pressure chamber drilled and tapped holes.

See our new Online Order Page for ordering Kits and accessories.

Kit Contents

Go here for specific information on the contents of the kits and availability of pre-assembled launchers.

Local Parts Sources

Schedule 40 PVC is readily available in most areas. It may require visiting a plumbing supply or electrical supply outlet. USE ONLY SCHEDULE 40 PRESSURE RATED PVC IN THE PRESSURE SECTION including the pressure chamber and into the valve (or the stronger schedule 80). After the valve the pressure is much lower, but Schedule 40 is still recommended for sturdiness. (SDR 21 2.5" is slightly less sturdy but good for the barrel as it fits the tennis balls more loosely than schedule 40 which is a bit tight). Be sure the pipes you buy are actually Schedule 40. Schedule 40 pipe is marked every so many inches and shows a pressure rating. Buy a little extra pipe so you can clean up the ends - they are often scratched and not well cut.
The 2.5" Schedule 40 PVC is not as available as other sizes, but is chosen to fit the tennis balls. It is a very tight fit. The SDR 21 2.5" is harder to find but fits tennis balls better and weighs less. It is a bit more fragile being 0.137 thick instead of 0.203.
2.5" grey Schedule 40 PVC is often available in the electrical conduit section of hardware stores, or at electrical supply outlets. The grey Schedule 40 PVC should be fine for barrel material. The plumbing type 2.5" schedule 40 is usually white. The 2.5" schedule 40 pipe and endcap can be obtained from www.usplastic.com if they cannot be found locally. Orchard Supply Hardware carries the 2.5" fittings and pipe, and they sell pipe by the foot, for those who have access to that chain of stores.
Many sprinkler valves are available and some others may be suitable for this design. The Rainbird models generally have slightly better flow and have been tested and are recommended. Other brands may be more difficult to modify for pneumatic actuation. The Rainbird models are available from www.sprinklerwarehouse.com. If you use something else and it works well, let me know and I'll add it to the list. Orbit Watermasters are popular, though I have not tested them. A 1" flow diameter is recommended for tennis balls. 3/4" flow is much less effective - it has only half the flow. Smaller valves constrict the flow and reduce performance significantly. Larger diameter valves may work very well, but they tend to get large, heavy and expensive. The one inch is a nice compromise and is adequate for this design.
The machined brass 1/4" npt street elbow that I used is very short. There are cast units that are a bit longer. I think the shorter machined type are a better choice here. Check a couple of different hardware stores, some seem to carry the machined type, some the cast ones. I have found the machined ones at YardBirds and Home Depot.
The trigger valve shown is available from Harbor Freight tools. [ NOTE (1/2008) the Harbor Freight finger trigger was changed in late 2007 and the new model has inadequate flow. The thumb type trigger works better, though it requires a double male 1/4 NPT short adapter to fit... ] Most any air duster or blowgun should work, as long as it has decent airflow. It is best if it does not have flow limitations built in (or they are removed). Tips that limit flow can be removed, generally, or cut off. Valves that say "for use on 30 psi (or less) regulated lines" are good - they don't contain internal regulators. Valves that contain internal regulators or flow limiters or are low-flow are not as good. These may be marked 'complies with OSHA safety regulations' and rated for pressures above 30 psi. The goal here is to depressurize the pilot volume of the sprinkler valve quickly. This requires good diameter passageways all the way through the valve. A low flow valve will lengthen this time and cause the sprinkler valve to move more slowly. The net result may be lower performance (reducing the maximum trajectory height). If you are unsure about the flow volume of your trigger valve then you can elect to not epoxy the valve in place until height testing has verified adequate system performance. Use teflon tape and epoxy the valve later, if desired, after performance has been verified. Valve 'honking' is a possible indication of low performance.

CSVxx Antenna Launcher Kit Assembly

The kit builder should read all the instructions about cutting and preparing the parts as some steps may be required - such as deburring, filing off sharp sprue, etc, even though the precision boring and cutting is already complete. They should clean and inspect the parts and follow the instructions for cementing and assembly in the general assembly instructions below.

Recommended Tools and Supplies required for Kit Assembly

PVC Purple Primer, small can (dauber in can)
Clear PVC cement, small can (dauber in can)
Epoxy, one or possibly several small kits - syringes or tubes
Several mixing cups and stirrers (unless the epoxy comes with mixing attachments)
Rubbing alcohol/water (for cleaning, no additives as they may interfere with glue bonding)
File
Sandpaper, medium and fine
Drill and 5/16 drill bit
1/8 NPT Tap and handle (or small C clamp or wrench to turn it)
Wrenches for turning in Schrader and Gauge
Philips screwdriver for Sprinkler Valve disassembly
Stack of folded newspapers (to catch glue drips)
Masking tape (3M blue type is good)

CSVxx Antenna Launcher General Assembly Instructions

These instructions are merely a guide of what has worked for us - think through your plan and understand what you are doing. Plan your work, and work your plan... Cemented joints are very good, but hard to change later... Read all instructions before starting. Reread each step through before performing. The cementing is essentially a binary combination process. In each stage as many components are joined in separate subassemblies as possible. In subsequent steps these subassemblies are combined. There are many other ways to do this, but if you decide to change the order be very sure that the new order works.

The quality of your work affects the safety of the finished launcher. Just the other day I read about someone who completely forgot to glue one of their joints in the pressure section of their launcher (a design of their own, not this one). The parts were wedged together very tightly (this can happen while trial fitting - be careful). It held for awhile, then let go with a bang at high pressure. The PVC part that came off turned into a projectile and bounced around their shop and broke the overhead lights, sending a shower of broken glass down on the builder. These joints, done properly, have a significant safety margin. Do them well.

Above all - BE SAFE.

Parts Preparation

Cutting PVC Pipe

I use carbide blades in the radial arm saw to cut PVC pipe. It may also be cut with a hacksaw, bandsaw, or other fine tooth saw. After cutting it is good to deburr and slightly round the sharp edges with a file, sandpaper or deburring tool. A sharp edge on the pipe can reportedly scrape the cement away and cause a potential weak spot in the joint. One fellow reports that he puts his PVC parts into the bathtub with warm water and goes after the outside surfaces with SOS pads or equivalent. This makes the PVC look great and it will take paint well. The fittings are usually much better looking, and you can pick through them when buying. Purchasing a cut length doesn't allow the flexibility of inspecting the piece ahead of time. If you plan to paint the fittings lightly sanding off the slick finish will help the paint adhere.

Krylon makes paint specifically for plastic called Krylon Fusion. It works well on PVC.

The pipe we are using is not necessarily 'pretty' when it is purchased - it may have scratches, rust stains, etc from the storage and transportation. Make sure the material is sound - not cracked or fractured or deeply scarred with scratches. Occasionally I have to throw some away due to these flaws, especially in the larger diameters and near the ends. The pipe looks a lot better after scrubbing with a fine steel wool type pot scrubbing pad.

It is important to avoid cracking or fracturing the PVC when working with it. Use sharp tools and avoid cutting too fast. Even minor fractures can lead to failure later on. This can be a problem when drilling, tapping, boring, or cutting the PVC. Any fractured PVC should be recut to remove fractured parts or discarded.

CSV19 Antenna Launcher Cut Schedule

Note that if you have a kit all the cutting is already done.

cut a .40" slice off the 1" coupler, making a ring. This will be the reinforcing ring inside the pressure chamber.
cut two pieces of 1" schedule 40 PVC pipe: The following dimensions are approximate, adjust to fit your parts. The first to be 1.75" (1.25:1" bushing depth plus sprinkler valve socket 0.75"). My uncut bushing measures about 1.08 socket depth, plus the 0.75 sprinkler would be about 1.83". Your parts may vary, measure to be sure.
The second to be approximately 1.5" (sprinkler valve socket 0.75" plus endcap and gap thickness (.42") plus coupler ring slice (approx .40")). [ NOTE this part has been changed to schedule 80 to reduce breakage - optional. ] The easiest way to do this is by trial fitting. Put a piece of 1" pipe into the endcap. Put the coupler ring on the inside. Adjust the pipe to be flush with the end of the coupler ring, while the coupler ring is against the inside of the endcap. Mark the pipe on the outside of the endcap. Add 3/4" for the sprinkler valve socket, and cut the pipe there. The goal is to have a joint at least 0.75" deep in the endcap/coupler. A bit more is fine.
The 1.25" pipe should be cut just long enough to fully fill the two 1.25" elbow sockets to their full depth without separating them apart. Measure the depth of one socket and double that, cut to that length. In my case the elbow sockets are 1.25" deep, so this part is 2.5" long.
Other pieces should be cut to the lengths shown in the parts list above.

Preparing the End Caps

I use a metal lathe to bore holes in endcaps. These holes must be very close fitting and cleanly cut for a good safe joint. I make it a close fit - approx 0.010" clearance - the parts should optimally go together with some friction.

Bore the Pressure Chamber Endcap to closely fit 1" pipe.
Bore the Barrel 2.5" Endcap to closely fit the outside of one arm of the 1.25" elbow. When fitting to the elbow choose the clean round end of the elbow. The raised lettering, etc interferes with the fit. You may need to file lumps on the elbow slightly to get a good round surface for a close fit all the way down to the shoulder. The completed elbow should protrude into the endcap about 1/8" minimum. Mark this elbow end to go in the bore endcap later to avoid using orienting it incorrectly.
Remove the Casting Sprue from the Endcaps. The three endcaps may have sizable sharp casting sprues on them. It is optional, but a good idea to file these down to avoid injury from the sharp edges. When glueing you may wish to place these bumps on the 'inside' toward the barrel or pressure chamber opposite.

Preparing the Sprinkler Valve

These instructions assume the Rainbird 100-DV-SS valve, others may vary. If you get the kit or prepared valve you can skip the valve preparation steps that have already been done (drilling, tapping, milling), however it is best to disassemble the valve and reassemble it after glueing and mounting the trigger.
Remove and discard the small manual actuation valve screw and the large solenoid. These are both threaded into the valve top.
Remove the top of the sprinkler valve (6 screws). Observe the compression of the rubber diaphragm gasket on the side of the valve before removing the screws to aid in reassembly later. The edge of the rubber gasket squeezes out just slightly convex when the screws are tightened properly.
I screw the valve top to a 6 to 8 inch long piece of 2 by 4 using two of its original screws. Predrill holes into the 2x4 to make the job easier. I had to drill a clearance hole in the 2x4 under the center of the valve to clear the tap -5/8 diameter by 1/2 inch deep centered between the two small holes should do. This makes it easy to work on the valve top.
Drill and tap the sprinkler valve 1/4-18 NPT in the center of the top. The drill size recommended by my 1/4-18 NPT tap is 7/16". Drilling a 1/8" pilot hole first is recommended. Alternately a Unibit(tm) type step-drill may be used if you have the right size. They work well in plastic.
Tap the hole 1/4 NPT. Tap without lubrication, but work the tap back and forth as you go forward to cut the PVC. Take care to keep the tap square and straight. Tap deep enough but not too deep. Usually only about 2/3 of the tap should be run into the hole. Tap deeper until the diameter is large enough for the brass street elbow. It needs to be tapped to fit the particular part being installed. Check by running the tap in halfway first, then removing the tap and testing with the brass street elbow. Do not force the elbow in if the threads are too small, run the tap deeper and try again. It should not get tight in the threads too early. You want it to sit deep enough to have good strength, fully engaged with the threads in the plastic, approximately 3 turns. The threads should be tight to hold the trigger in position. The end of the brass street 90 should just go through the plastic threaded area and not protrude into the inside of the valve. The further it sticks in, the less the valve will be able to open. If it does not open fully it will reduce the flow in the valve slightly. There is a little dome inside the valve. The end of the brass should be flush with the top of the little dome, approximately 1/8" above the rest of the inside surface. Take care to get the tap in very straight when you start it. One way to do this is to remove the drive belt from a drill press and hand turn it. Do not use the motor! Once started it may be easier to take it out of the press and finish the tapping by hand.
Lower the sprinkler valve electric solenoid port - Sand or cut off the top 2/3 of the solenoid port tube (after removing the solenoid) to allow clearance for the installation of the trigger valve assembly. Less than 1/8" should remain sticking above the valve top. It should be low enough so the trigger handle does not strike the port tube when screwing the 1/4 NPT trigger/handle/street elbow onto the valve. My favorite tool for this is the mill, or the belt sander.. It may be hacksawed, filed or sanded off instead. Perhaps a large forstner bit on the drill press would work well also --
(Optional) Counter drill the solenoid center port from the top, 1/8" dia by 1/8" deep to aid in getting epoxy into the hole to block it off.

Solvent Cementing Procedures (EVERYONE READ)

Always use PVC primer! Purple is BEST!!!
Use clear cement. Avoid fast setting 'blue' or other PVC cements. They are not as strong, and this stuff sets fast enough already.
Do not use primer or cement that is thick, lumpy or otherwise questionable. Get new primer and cement if there is any question.
Clean and dry the PVC, sand off the sharp corners inside and outside.
Follow instructions on the primer and cement.
The primer is very thin and volatile.
Hold the parts tipped downward so the primer that runs will not make a mess all over the part.
Do not set parts on contaminated newspaper.
Use adequate primer and cement -- especially in the bottom 2/3 of the joint where the strength and seal is strongest.
You may want to mask the pipe to prevent primer and cement from marking them where you don't want them to. Blue masking tape works well. On the PVC joints get a good coat of PVC primer on. It does not have to be wet when the cement goes on, but it should be pretty evenly purple.
On the 2" and larger pipes use plenty of cement - it takes more cement on the large joints to avoid a leak.
Use PVC primer and cement in a well ventilated area.
Use a stack of folded newspapers to control drips, set layers aside when dripped on to avoid getting primer/cement where you don't want it.
Push the joint quickly together while twisting it and get it properly aligned immediately. The solvent cement sets quickly.
Hold the joint till it sets, plus some margin. Perhaps a minute.
On tightly tapered joints hold longer or clamp to prevent creep. The sprinkler valve joints are quite likely to spring out if not clamped.

Epoxy Gluing Procedures (EVERYONE READ)

Note - if you have a "Super Kit" the epoxy has already been applied to the valve top, and the other epoxy operations can be skipped.

Epoxy Selection

Devcon 2-ton is my favorite. Nearly clear. 1:1 mix - easy (all these epoxies are 1:1 mix). Not as thick as most others, good work time, self-levelling. Nice finish. Sets in 30 minutes. Gives you enough time to get things right. Handle in 2 hours. Full strength in 8 hours. (So they say, strength actually builds for a week or so. Note that their testing protocol specifies one week cure.) I like the 9 oz bottles - they are not messy to use, keep a long time, and cost effective ($9-14). I have used the 9 ounce kit for quite a few projects over many years and there are still 3 ounces left in my first bottles, and it still works fine, though it is long past the printed expiration date. I purchased another set recently at an Ace hardware. My original set came from a hobby store. The current website information seems to indicate that the tubes are 50ml, the syringes are 25ml and the bottles are 400 ml.
One of the small kits - tubes or syringes - is about enough for this launcher. I usually use about 39 ml total for all the epoxy joints. [ NOTE - using much less epoxy now (3/08) since it is only required on the valve top. It is now optional on the pressure chamber and barrel endcap. ] The kits are available at most hardware stores. The syringes are the most convenient (when new) way to get the 1:1 mix quickly. If you buy the larger bottles you will have about 80 percent left over, but it should be viable for years. The tubes and syringes are fine when new, but after a few months may become a leaky mess. My experience in the past was as the syringes age they become increasingly difficult to move evenly and the 1:1 mix becomes more difficult to achieve. Perhaps they have improved. They should work fine when new.
EPOXY News - the automatic mixing syringes work very nicely for the barrel endcap (now OPTIONAL). They mix instantly as you squeeze it into the joint so even though they contain 14ml of 5 minute epoxy there is no problem with it setting up too early. The long mixing tube really works well to direct the epoxy into the small space of the barrel endcap. For the rest of the joints a standard double syringe (25 ml) of the 30 minute 2-ton epoxy works well. These kits are available on the order page, and there is a special instruction page for using these when building the launcher here.
Devcon 5 minute? Thickerer, as they used to say about - what was it, peanut butter? Too fast? It works well with the flowmix system since no time is spent mixing. I'm not so crazy about 5 minute epoxy for the other joints. You mix like a madman for 60 seconds, and then you are almost out of time. The stuff is thicker, harder to apply, and gets quite hot. I do use it some of the time, it works well, but you have to be organized and get things in the right positions right away. Also available in a 9 oz kit - I found one at Orchard Supply Hardware. The 5 minute epoxy is used extensively in flying model airplanes these days. I suppose it allows them to crash more often.
JB Weld? Popular. Dark grey. very strong. Good on PVC. Fairly thin - slightly thicker than 2-ton above. Available in tubes (messy). Full strength in 24 hours. Machinable. Contains metal (stainless steel powder?). Works Well!
Devcon Hi-strength Plastic Welder? 4 minute set time - very short time. Nasty smell, melts my plastic mixing cups. Very strong. Very thick. Thickest. Cream color. Thixotropic - doesn't flow - stays where you put it, including whatever marks you left in it. Stringy, leaves filaments as you take the spatula away. Probably great when you need really high strength with plastic. Available in dual-syringes, which are often messy if you want to use it a little at a time. Rated for PVC. Probably a great choice if you can work really really really fast and get it to go where you want it. If you choose this I would recommend several small batches, divide the job into small steps. You have about a minute to mix and apply.

Bottom line - get either one 14ml double-syringe of flow-mix, or one 25ml double-syringe of 2-ton epoxy and three small mixing cups (1 oz) and one larger cup (2 oz) plus four mixing stirrers. Or get the kit from the order page.

Preparation for Epoxy (EVERYONE READ)

Since Epoxy will not solvate the PVC it is useful to lightly sand the surfaces to be joined with fine sandpaper.
Surfaces must be Clean, Dust-Free and dry. It is really a good idea to wash the PVC with soap and water, and use a pot scrubber (fine steel wool) on the PVC pipe parts. (DO NOT scrub painted barrels, only bare ones).
Clean with rubbing alcohol that has only alcohol and water content. 91% or better alcohol is available for $1 per pint at drugstores for antiseptic use - this is the b0st. Be careful with 70% as additives are sometimes a problem with cement.
Follow the Epoxy manufacturer's Instructions

Mixing Epoxy (EVERYONE READ)

Use clean plastic or paper small cup.
Smart and Final has very nifty little cups (1-2 oz souffle cups $2/200) and stirring sticks (5-1/2" round end wood stirrers $2/1000). Small paper drink cups from the grocery store work well also, and slicing up a small dowel for stirring sticks.
Mix thoroughly and vigorously for 1 minute.

Threaded Joints

The use of teflon tape is recommended. If you use it use 2-3 turns.
Install CAREFULLY DO NOT CROSS THREAD!
Do not over tighten.

CSV19 Launcher Assembly Photos

The Valve Top above has been prepared by epoxying closed the three small openings (two are visible in the solenoid socket, the third is under the trigger valve). The Trigger has been epoxied into the brass elbow and that epoxied into the sprinkler valve top in the proper position between the mounting screws. [ NOTE - I no longer epoxy or glue the trigger. ]

The endcap above has been bored to closely fit the short pipe and the pipe solvent cemented into the hole. The supporting ring has been solvent cemented around the pipe inside the endcap, and a puddle of epoxy has been poured around the support ring to lock it in place. [ NOTE - the epoxy is optional here. ]

The three photos above show the drilling and tapping of the pressure chamber for the fill valve and the pressure gauge. It is drilled in the double thick area to provide maximum support for the threads.

CSV19 Antenna Launcher Parts Assembly (EVERYONE)

	Clearly familiarize yourself with all parts before proceeding. Trial fit them loosely together to insure that they are all accounted for and the fit is snug. Be careful in trial fitting them as they can stick together if inserted too far. Do not insert them with any force - stop when slight resistance is felt. It is normal for them to fit tightly - the cement lubricates the joints during assembly so they can be fully inserted. Y
	Wash the PVC pipes and tubes. This includes the barrel pipe, pressure chamber pipe and the three joiner pipes for the launcher. Use a steel wool type pot scrubber to get them clean. Washing the other PVC parts is optional, and avoid the steel wool potscrubber on the shiny finish of the fittings, as it may scratch and dull them. Use soap and water with a washcloth to clean the fittings. Dry the PVC before glueing.
	OPTIONAL - Paint the barrel with Krylon fusion spray paint. Mask off 1-3/4" at one end to keep it clean of paint for cementing to the launcher. We use Safety Blue. The Pressure Chamber may also be painted, mask off both ends and keep them paint free about 1-3/4" for cementing.
	Solvent cement the ramrod handle (1/2" pipe) into the ramrod bushing (1/2 by 1.5 or 2"). Insure that the pipe is fully into the socket. Note that these parts often fit together so tightly without cement that cementing may be optional, but this is a good part to practice on. NOTE that wherever the instructions say "solvent cement" you should use PVC primer and PVC cement. EPOXY will be specified for the few joints it is to be used.
	Locate the 1.25" elbow that has been fitted to the bored hole in the 2.5" endcap. Observe that the elbow has one end that fits better into the barrel endcap than the other due to the raised lettering that interferes with the tight hole in the endcap. Reserve the better fitting end for the barrel endcap - mark it.
	Solvent cement the 1.25" short joiner pipe into the other end of this barrel elbow. (Note that the 1.25" is the pipe size, the actual size is closer to 1.5" in diameter - these are pipe sizes.) Prime the interior socket of the elbow with purple primer, and half the 1.25" short joining pipe. Coat the socket and half the pipe with a coat of PVC cement. Stand the 1.25" pipe with the cemented end up on the work surface. Push the elbow down onto the pipe until it is fully seated. Clean off the excess glue and set aside to dry.
	Solvent cement the 1" to 1.25" bushing into one end of the other 1.25" elbow. One end of the elbow has two mold lines. Cement the bushing into the end that does not have mold lines (as these lines aid in alignment of the elbow during a later step). If the bushing has been shortened it will fit approximately flush, otherwise it will stick out a bit. MAKE SURE that the bushing is installed the right way. The stop ring should not interfere with the later installation of the 1" pipe inside to a depth of 3/4". NOTE that wherever the instructions say "solvent cement" you should use PVC primer and PVC cement. Prime both the pipe and the socket with purple primer, then coat both surfaces with a thin layer of cement. Set the bushing with the internal stop ring up on a paper towel on the work surface. Push the elbow fully down on the bushing. Push against a paper towel on the benchtop to seat the bushing fully in. Wipe up excess cement with paper towels and Q tips.
	Solvent cement the 1" diameter short pipe and ring into the bored hole in the large pressure chamber endcap. NOTE - after 9/15/05 this short pipe is supplied using the stronger schedule 80 material. It is dark grey rather than the usual white PVC. It is installed using the same procedure and cement as before. (Depending on your parts it might be a slightly different length. It should fill the coupler ring, the endcap and have enough left sticking out to fully fill the valve socket - 3/4". See the cut schedule above for details). This joint holds full pressure for extended periods so it is imortant that it be a good joint. Prepare the endcap, masking it on the inside to protect the inside vertical glueing surfaces to be used later for the pressure chamber pipe. Position the 1" pipe so it extends into the endcap about 1/3 of an inch. There should be 0.75" of the pipe sticking out of the endcap to fit the socket in the sprinkler valve. (This may need to be adjusted depending on your particular sprinkler valve socket depth). Wrap masking tape around the 1" pipe where it extends from the endcap to mark where it should sit and discourage cement leakage there. The joint should be tight enough that the cement will not leak. Test the ring on the pipe inside the endcap. Clear any burrs that interfere with installing the reinforcing ring over the 1" pipe. Remove the ring and set it aside. Remove the pipe from the endcap. Using a Q-tip type cotton swab on a stick applicator to apply purple primer to the inside of the hole bored in the endcap, and to the inside of the reinforcing ring. Apply purple primer to the pipe end that is not masked. Apply cement to the hole in the endcap, and to the pipe. Slide the pipe into the endcap up to the masking tape. Apply cement to the inside of the coupler ring and slide that onto the end of the pipe inside the endcap until it contacts the inside of the endcap. After a minute or two remove the masking tape from the 1" pipe and clean up the excess cement.
	Disassemble the Main Valve by removing the six screws that hold the valve top to the valve body. Remove and set aside the rubber diaphragm and spring and screws. Note how the diaphragm and top are aligned for later re-assembly.
	Epoxy the three small holes in the valve top. One is the manual actuation port. The other two small holes are the solenoid input and output ports. The inlet port is a small hole in the bottom corner of the solenoid socket. The outlet port is in the center of the solenoid socket. Clean the areas with alcohol. For proper epoxy adhesion these areas must be clean. Mask the inside/bottom of the cap to prevent epoxy from going beyond the three holes toward the inside of the valve. Blue masking tape is good for this, it does not leave adhesive residue. Carefully dribble epoxy down into the small threaded hole (the manual actuation hole). Apply epoxy into the larger threaded solenoid socket and insure that both small holes in it are plugged by the epoxy. This can be done with one large puddle or two small ones.
	Solvent cement the other 1" dia short pipe to the outlet of the sprinkler valve. This is the pipe that will go into the 1.25:1 bushing. (Depending on your parts it may have a slightly different length. The length should be enough to just fill the sprinkler valve and the bushing). Hold and clamp it tightly - the sockets on the sprinkler valves are tapered and the pipe can creep out if not held in tightly for a few minutes.
	Solvent cement the solid pressure chamber endcap on the end of the pressure chamber pipe. Always use purple primer on solvent cemented PVC joints. Get a good coat of primer on both joint surfaces - inside the socket and outside the pipe. This is a large joint, use plenty of cement. Large joints can leak or stick before fully seated if insufficient cement is used. Get it all the way out to the edge to avoid a leak when the holes are drilled and tapped into the plastic later.
	Take a Glue Drying Break. The durations of these breaks are dependent on the cement that is being waited on, and the stress of the next step. Solvent joints can be handled fairly soon, epoxy really depends on the particular cement. Follow manufacturers recommendations. In general, 8 to 24 hours should be sufficient. An easy way to do this is to stop at the glue breaks for the day and start fresh the next day.
	[ OPTIONAL - it is no longer required to use epoxy in the endcaps. ] Make a mask to protect the inside of the pressure chamber endcap from epoxy using four 3 by 5 inch cards. Lay them out in a line, overlapping them by about one inch. They should cover an area about 3.5 inches by 15 inches. Tape them into this arrangement. Alternately, a piece of heavy paper or thin cardboard may be cut to 3" by 15".
	[ OPTIONAL - it is no longer required to use epoxy in the endcaps. ] Epoxy support the pressure chamber exit pipe. Support the endcap so that it is level. Wrap the cardboard mask into a ring and position it inside the endcap against the inside cement surface to protect it from epoxy splash. Mix a batch of epoxy thoroughly and pour a puddle of epoxy around the 1" pipe inside the endcap. Approximately 20 mL, or half of a 2 ounce epoxy kit (a kit of two 1 oz tubes of 1:1 epoxy and hardener) should be enough. The epoxy puddle should support the pipe/coupler ring to a depth of approximately 0.2". Allow to set overnight, insuring that it stays in the proper orientation with the pipe, keeping the endcap level. Use a level to insure that it is actually level before leaving it to cure.
	Install the trigger valve to the street elbow using teflon tape. Starting in late 2007 the trigger valves supplied are female threaded and this requires a short threaded adapter pipe. IMPORTANT - Remove the tip, if any, from the air duster and discard it. Good airflow is requires for proper launcher operation. Thread the air duster into the brass elbow. Use the double male adapter tube if required. Position the street elbow such that, with the outlet tip of the air dister pointed away from you the brass elbow male threads point to the left. The threads should be tight. The flat side of the brass elbow should be parallel to the flat of the handle. The solenoid attachment hole that you filled earlier sits toward the rear of the launcher. The solenoid socket is toward you and the valve top oriented so the valve would be to the left. The male streen 90 threads then screw into the valve top center about 3 to 4 turns. The trigger should sit over the small threaded hole (the manual actuator hole) and between two mounting screw holes. Place the two screws into the holes before positioning and insure that the screwdriver access past the blowgun handle is ok. On the inside of the valve top the street elbow should even with or just barely enter the valve. The brass should be above the flat level of the interior of the valve where the diaphragm moves by about 1/8".. It should not protrude into the valve and limit the diaphragm motion.
	Solvent cement the second 90 degree elbow to the other end of the short 1.25" diameter pipe that is already cemented to the other elbow. Insure that it is fully together and flat and the open ends of the elbows are pointed the same direction. This forms the U assembly.
	Solvent cement the pressure chamber pipe with cap into the other endcap (with the outlet pipe). This is another big joint - use plenty of cement.
	Take a Glue Drying Break
	Solvent Cement the U assembly into the 2.5" barrel endcap. Using masking tape, cover the inside of the endcap where the barrel will be glued later to prevent cement from spreading there. Use PVC primer and cement. You can apply the primer with a Q tip to prevent it getting where you don't want it. Then apply PVC cement to both the inside of the bored hole and the outside of the elbow. Position the endcap as far as it will go onto the elbow without forcing it. If forced too far it will not be concentric with the elbow.
	Take a Glue Drying Break
	[ NOTE - this epoxy is optional. ] Prop the elbow and endcap level to make the epoxy flow properly. This is a good joint to use the flow-mix epoxy on, if you have any. I have used a whole 14ml flowmix kit for this joint. The long nozzle gets it down into the joint easily. Or, mix a batch of epoxy and carefully pour it into the endcap around the elbow. Insure that it remains supported and undisturbed while the epoxy cures, and that the proper angle is maintained.
	Drill and tap the two holes into the pressure chamber 1/8-27 NPT. [ NOTE - if installing a pressure relief valve there will be three 1/8 NPT holes to drill and tap. ] Locate them along a straight line parallel to the axis of the chamber, close to the barrel. Each hole should be about 1.5" from the 'edge' of the endcap. Drill a 1/8" hole first, then enlarge with a 5/16 drill. The tap recommends a larger drill but in plastic I prefer a slightly smaller hole and allow the tap to finish the hole. The most difficult part of the drilling/tapping is getting the hole perpendicular to the surface. Take some care to do so, and keep the tap straight into the hole so the gauge and schrader valve come out straight when installed. Tap without lubrication, but work the tap back and forth as you go forward to cut the PVC. The tap is tapered - the deeper you run it in, the larger the hole and threads. Approximately 1/2 to 2/3 of the tap cutting threads has worked well for me - this makes the threads fairly tight for a good seal.
	Clean out the PVC dust - use plenty of compressed air or rinse repeatedly with water. This dust may interfere with valve sealing if not completely removed. (If the launcher leaks from PVC dust, just disassemble and clean the valve).
	Take a Glue Drying Break
	Solvent cement the valve outlet tube into the bushing of the barrel assembly. Align the barrel assembly with the valve quickly before the glue sets. The valve top should be parallel to the elbows, the trigger handle should sit alongside the barrel. You may wish to temporarily install the valve top and trigger assembly to aid in alignment. Refer to the photos. Clamp or hold in position until set.
	Take a Glue Drying Break
	Solvent Cement the pressure chamber assembly to the valve inlet. If it is wet from cleaning out the dust, allow it to dry first. This is a critical joint, be sure to clean, purple prime, solvent cement and clamp it well. This is a tight tapered joint, clamp it tightly to avoid creep. Observe the alignment of the holes for the gauge and schrader valve slightly to the right of the barrel when viewed from behind. Make sure there is enough clearance for the gauge and access to the schrader valve for filling. Refer to the photographs for additional guidance.
	Take a Glue Drying Break
	OPTIONAL - if you have a pressure relief valve (they are included in some kits, and are available as an optional item on the order form), drill and tap a third hole opposite the gauge hole on the 'back' side of the barrel, about 1.5 inches from the edge of the endcap. Trial fit the barrel to help find the position for this hole. Placing the pressure relief valve close to the barrel will allow the launcher to lie on a flat surface without touching the relief valve. Install the pressure relief valve in this hole.
	Install the schrader valve and gauge on the pressure chamber. Locate the pressure gauge toward the rear next to the trigger valve, and the schrader valve toward the front of the Launcher.
	Solvent cement the barrel into the 2.5" endcap.
	NOTE - DO NOT GLUE THE REEL TO THE BARREL. The reel is a friction fit for portability and ease of use.
	Take a 24 Hour Glue Drying Break!!!!!!!!!!!!
	Install the valve top/trigger assembly. Align the top of the sprinkler valve with the body by lining up the hole under the solenoid socket (now epoxy filled) with the hole in the diaphragm gasket and valve seat next to the valve outlet port. When starting each screw, turn it slowly backward until it 'clicks' into the thread previously cut, then turn gently forward and slide into the existing thread cut. The screw should go in easily and not start cutting new threads. Carefully tighten the screws in rotation. Do not over-tighten. Observe the compresssion of the rubber diaphragm gasket at the edge of the valve top as the screws are tightened in rotation. The rubber gasked should just show stress at the edges where the plastic is compressing it when adequate tension is reached. A power screwdriver is NOT recommended for this task - the feel of a manual screwdriver is preferred.
	New CSV19 Super kits are supplied with a Cable Tie and a barrel to chamber spacer. Tieing the barrel to the chamber increases the strength of the system which can reduce breakage if the launcher is dropped on a hard surface. The supplied spacer is a short length of 1/2" PVC square rod with double stick foam tape on the ends. This is the right spacing for most launchers, but some will require a different length spacer. Cut a new spacer from a length of dowel or other suitable material if needed. Remove the cover from the foam tape and insert the spacer between the barrel and chamber. Stick it to the chamber and barrel. Wrap the large cable tie around the barrel and chamber and tighten with the joint on the back side of the launcher. Carefully cut off the excess flush with a utility knife. NOTE: The CSV17 has a much larger spacing between the barrel and the chamber due to the smaller chamber diameter. The spacer needs to be much longer, and I have not found an appropriate spacer for the CSV17. It is not required for proper operation.

Testing

Pressure Safety Test

Wrap the launcher in several layers of blanket or other material to absorb any pieces if it comes apart.
Wear safety glasses, gloves and long sleeved jacket in case of pressure failure.
Pressurize the launcher to 100 psi and let sit for 15 minutes. If a pressure relief valve is installed use slightly less pressure to avoid triggering the valve.
It may leak down, add pressure to maintain 100 psi every few minutes.
Drain the pressure through the schrader and apply the maximum pressure sticker to the launcher barrel or chamber near the tank fill valve.

Leak Test

Fill to 40 psi.
Observe the gauge.
If it moves perciptibly downward in less than 30 seconds you may want to find and fix the leaks.
Use soapy water. Do not immerse the gauge in water. Best is to use a spray bottle or bucket and rag and selectively spray or wet the test area.
Take care not to over-tighten the threaded fittings. Removing them and replacing the teflon tape often helps stop leaks.
If the valve leaks (noise in the barrel) try a few dry-fires and see if it still does. If so, disassemble the valve and clean the seat and diaphragm and reassemble and retest.

Launch Test

The first few tests at up to 30 psi can be done with limited space, in the garage or backyard.
MAKE SURE YOU KNOW WHERE YOUR RAMROD IS (NOT in the barrel). If you store it in the bore, and launch it, you will have a very high velocity projectile. Launching the ramrod may damage it and whatever it hits. Wrapping red tape around the end of the ramrod handle is a good idea. MAKE SURE THE HANDLE IS LONG ENOUGH IT ALWAYS STICKS OUT of the bore, even without a tennis ball in there. ALWAYS TEST IN A SAFE DIRECTION, EVEN WHEN LAUNCHER IS EMPTY.
Pressurize to 20 psi and dry-fire. Note that if you squeeze the trigger the valve slowly the launcher may operate with less than full power. It may 'honk', especially with no tennis ball, indicating that the valve is oscillating. Depress the trigger quickly to speed the valve's opening. Depress it quickly but smoothly - avoid jerking the whole launcher. Weighted tennis balls tend to improve valve performance and reduce this effect.
Try several test dry-fires at 20 psi, pulling the trigger slowly and fast and see if you can hear the difference. Pulling the trigger too slowly may cause the ball to reach a lower velocity and height.
Load a tennis ball and pressurize to 20 psi. If you have a schedule 40 barrel, it takes considerable force to push the tennis ball into the barrel - this is normal. If you have an SDR21 barrel (thinner PVC) the tennis ball will fit easily into the barrel. The ramrod end pushes on the edges of the ball which tends to lower the force required. If you push on the center of the ball it swells and becomes tighter in the bore.
Launch the tennis ball in a safe direction. It will not have much force at all if you have a tight barrel. It might even stick in the barrel.
Pressurize to 30 psi. At this pressure it will have moderate velocity and may bounce around the garage. With an SDR21 barrel it will have even more velocity, so be careful.
Beyond 30 psi you need more space or a better backstop. You can launch upward (make sure it will fall in safe area) or into a strong fence (it will rebound strongly).
Carefully test with 40 psi. Velocity should be considerable.
Save pressures above 40 psi for the field where you have lots of room. Always consider where the tennis ball is going to go before launching it. Be safe.

Fishing Reel Adapter

The simple fishing reel attachment is a 2.5" coupler with the fishing reel strapped to it with two stainless steel hose clamps. When attaching a fishing reel, hold it down with a hose clamp at each end of the reel foot. The front of the foot should be located at the front edge of the coupler. This coupler is NOT CEMENTED to the barrel - it is a friction fit so it can be removed for transport and while dealing with the line. Do not put it on the barrel too tightly - it can become difficult to remove.

Another very nice reel is the Saunder's Zip Reel. This large diameter reel can be adapted to a coupler is coaxial around the barrel. It feeds 21 inches of line per turn so it is easy to wind back on and presents a low resistance to the line going out. This is available pre-made by Eric WD6CMU. See our new Online Order Page for details on the availability of reel mounts and reels.

Have Fun and Be Safe!

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