There is an artical by W4SSY in the March 2009 QST Magazine. I am
planning to duplicate it for use at my QTH. I am interested in any
comments, especially from anyone who may have already built one.

My available trees may be about 80 feet so that is my minimum
expectations!

There is a lot of Google information available but I am trying to
focus on this example.

John Ferrell W8CCW

On Nov 27, 11:27�am, John Ferrell wrote:
There is an artical by W4SSY in the March 2009 QST Magazine. I am
planning to duplicate it for use at my QTH. I am interested in any
comments, especially from anyone who may have already built one.

My available trees may be about 80 feet so that is my minimum
expectations!

There is a lot of Google information available but I am trying to
focus on this example.

John Ferrell W8CCW

Hi John, I have not built one yet but am contemplating. Mine will
use a Rain Bird 1" Auto Sprinkler Valve, electrically actuated (24 VAC
or DC). I plan to use a Harbor Freigth 5 in one power source for the
air compressor, the pressure gage, and the 24 VAC actuator supply.
The power source is $60-$90 depending on the sale going on, it is also
handy for lots of other stuff.

This will be my first shot because I have this available. As far as
the PVC, tire valve, fishing reel, ect. don't have that much
experience. As far as line, I have had one break on me after a nice
launch with a sling shot. Make sure your line is of good quality.
Happy launching.

Gary N4AST

On Fri, 27 Nov 2009 17:13:50 -0800 (PST), Gary
wrote:

On Nov 27, 11:27?am, John Ferrell wrote:
There is an artical by W4SSY in the March 2009 QST Magazine. I am
planning to duplicate it for use at my QTH. I am interested in any
comments, especially from anyone who may have already built one.

My available trees may be about 80 feet so that is my minimum
expectations!

There is a lot of Google information available but I am trying to
focus on this example.

John Ferrell W8CCW

Hi John, I have not built one yet but am contemplating. Mine will
use a Rain Bird 1" Auto Sprinkler Valve, electrically actuated (24 VAC
or DC). I plan to use a Harbor Freigth 5 in one power source for the
air compressor, the pressure gage, and the 24 VAC actuator supply.
The power source is $60-$90 depending on the sale going on, it is also
handy for lots of other stuff.

This will be my first shot because I have this available. As far as
the PVC, tire valve, fishing reel, ect. don't have that much
experience. As far as line, I have had one break on me after a nice
launch with a sling shot. Make sure your line is of good quality.
Happy launching.

Gary N4AST
I bought most of the supplies last night at Home Depot. The Orbit
sprinkler valve was only about $12. It is an inline type valve like
the one in the artical. I was thinking I would use a long piece of
pipe as the accumulator but after doing the math I have decided to go
back and get a piece of 3 inch pipe to use. BTW, the cement and primer
is available in a single package for about $6.50. I am a little
concerned about the loose fit of the projectile in the 1-1/2 inch
barrel.

I will report back as I continue.
John Ferrell W8CCW

On Nov 28, 10:45�am, John Ferrell wrote:
On Fri, 27 Nov 2009 17:13:50 -0800 (PST), Gary
wrote:





On Nov 27, 11:27?am, John Ferrell wrote:
There is an artical by W4SSY in the March 2009 QST Magazine. I am
planning to duplicate it for use at my QTH. I am interested in any
comments, especially from anyone who may have already built one.

My available trees may be about 80 feet so that is my minimum
expectations!

There is a lot of Google information available but I am trying to
focus on this example.

John Ferrell W8CCW

Hi John, �I have not built one yet but am contemplating. �Mine will
use a Rain Bird 1" Auto Sprinkler Valve, electrically actuated (24 VAC
or DC). �I plan to use a Harbor Freigth 5 in one power source for the
air compressor, the pressure gage, and the 24 VAC actuator supply.
The power source is $60-$90 depending on the sale going on, it is also
handy for lots of other stuff.

This will be my first shot because I have this available. �As far as
the PVC, tire valve, fishing reel, ect. don't have that much
experience. �As far as line, I have had one break on me after a nice
launch with a sling shot. �Make sure your line is of good quality.
Happy launching.

Gary N4AST

I bought most of the supplies last night at Home Depot. The Orbit
sprinkler valve was only about $12. It is an inline type valve like
the one in the artical. I was thinking I would use a long piece of
pipe as the accumulator but after doing the math I have decided to go
back and get a piece of 3 inch pipe to use. BTW, the cement and primer
is available in a single package for about $6.50. I am a little
concerned about the loose fit of the projectile in the 1-1/2 inch
barrel.

I will report back as I continue.
John Ferrell W8CCW- Hide quoted text -

- Show quoted text -

I am sure you saw when Goggling that many use a Tennis ball with
pennies stuffed inside for weigth. That is what I intend to try, will
take a bit larger barrel than the one in the article. The tennis ball
will cause less damage if it comes down on a car window, or someones
head! Be interested to hear how yours works.

Gary N4AST

The pipe for the barrel is 1 1/4 in. 24 in. long. The end caps for the
projectile are 3/4 in. so there is not to much of a loose fit. I haven't
made one myself but a friend of mine has & it does just like the article
say's, use with caution & safety. I'm interested how it works with a tennis
ball, that sounds real neat. Howard K0ACF
"John Ferrell" wrote in message
...
On Fri, 27 Nov 2009 17:13:50 -0800 (PST), Gary
wrote:

On Nov 27, 11:27?am, John Ferrell wrote:
There is an artical by W4SSY in the March 2009 QST Magazine. I am
planning to duplicate it for use at my QTH. I am interested in any
comments, especially from anyone who may have already built one.

My available trees may be about 80 feet so that is my minimum
expectations!

There is a lot of Google information available but I am trying to
focus on this example.

John Ferrell W8CCW

Hi John, I have not built one yet but am contemplating. Mine will
use a Rain Bird 1" Auto Sprinkler Valve, electrically actuated (24 VAC
or DC). I plan to use a Harbor Freigth 5 in one power source for the
air compressor, the pressure gage, and the 24 VAC actuator supply.
The power source is $60-$90 depending on the sale going on, it is also
handy for lots of other stuff.

This will be my first shot because I have this available. As far as
the PVC, tire valve, fishing reel, ect. don't have that much
experience. As far as line, I have had one break on me after a nice
launch with a sling shot. Make sure your line is of good quality.
Happy launching.

Gary N4AST
I bought most of the supplies last night at Home Depot. The Orbit
sprinkler valve was only about $12. It is an inline type valve like
the one in the artical. I was thinking I would use a long piece of
pipe as the accumulator but after doing the math I have decided to go
back and get a piece of 3 inch pipe to use. BTW, the cement and primer
is available in a single package for about $6.50. I am a little
concerned about the loose fit of the projectile in the 1-1/2 inch
barrel.

I will report back as I continue.
John Ferrell W8CCW

"Howard K0ACF" wrote in message
...
The pipe for the barrel is 1 1/4 in. 24 in. long. The end caps for the
projectile are 3/4 in. so there is not to much of a loose fit. I haven't
made one myself but a friend of mine has & it does just like the article
say's, use with caution & safety. I'm interested how it works with a
tennis ball, that sounds real neat. Howard K0ACF
"John Ferrell" wrote in message

I don't have that QST but I built one like this:
http://www.qsl.net/k5lxp/projects/La.../Launcher.html

I did wrap a couple of layers of electrical tape over the end caps I used.
Found some orange electrical tape that I thought would make it easier to
see..
Still sort of loose in the pipe. At 35 psi it will shoot them to about 60
feet or more. My first trial shot put it over my triband beam that is about
55 feet up. Did not mean to do that but just wanted to get the feel of how
much psi I should use. I have found 45 psi will put it over the tops of the
trees here that are over 70 feet tall.

On Sun, 29 Nov 2009 10:17:37 -0500, "Ralph Mowery"
wrote:


"Howard K0ACF" wrote in message
.. .
The pipe for the barrel is 1 1/4 in. 24 in. long. The end caps for the
projectile are 3/4 in. so there is not to much of a loose fit. I haven't
made one myself but a friend of mine has & it does just like the article
say's, use with caution & safety. I'm interested how it works with a
tennis ball, that sounds real neat. Howard K0ACF
"John Ferrell" wrote in message

I don't have that QST but I built one like this:
http://www.qsl.net/k5lxp/projects/La.../Launcher.html

I did wrap a couple of layers of electrical tape over the end caps I used.
Found some orange electrical tape that I thought would make it easier to
see..
Still sort of loose in the pipe. At 35 psi it will shoot them to about 60
feet or more. My first trial shot put it over my triband beam that is about
55 feet up. Did not mean to do that but just wanted to get the feel of how
much psi I should use. I have found 45 psi will put it over the tops of the
trees here that are over 70 feet tall.


That is the model that I planned to use if the available Sprinkler
valve had that particular configuration. I was concerned about this
model because of the barrel and the tank being of equal volume. It is
good to have the testimony that it works as well! I be live it would
be easier to build and cost a little less as well. I would lean toward
the 1-1/4" barrel bore and the 3/4" tubing projectiles because I have
yet to see the 1" end caps described locally.

I may get to try a paper towel for a "patch" as used in Black powder
fire arms tomorrow. I am anxious to get up the 160 meter inverted L.

John Ferrell W8CCW

On Sat, 28 Nov 2009 11:45:12 -0500, John Ferrell
wrote:

On Fri, 27 Nov 2009 17:13:50 -0800 (PST), Gary
wrote:

On Nov 27, 11:27?am, John Ferrell wrote:
There is an artical by W4SSY in the March 2009 QST Magazine. I am
planning to duplicate it ...
... snip...
I bought most of the supplies last night at Home Depot. The Orbit
sprinkler valve was only about $12. It is an inline type valve like
the one in the artical. I was thinking I would use a long piece of
pipe as the accumulator but after doing the math I have decided to go
back and get a piece of 3 inch pipe to use. BTW, the cement and primer
is available in a single package for about $6.50. I am a little
concerned about the loose fit of the projectile in the 1-1/2 inch
barrel.

I will report back as I continue.
John Ferrell W8CCW

It is a 1-1/4" X 24" barrel, the projectiles are two 3/4" end caps on
about a 4" scrap of 3/4" PVC....

Test fire at 30 PSI dry.. it huffs and honks!
Next: 35 PSI and projectile nearly straight up... disappointing!
Next: 45 PSI and leaning towards the woods. Still not too impressing.
Next: 52 PSI about 75 degrees toward the woods. Whacked the tree
smartly at bout 60 feet or so...
Next: 55 PSI a little more vertical... overshot the tree with lots of
clearance and passed over several others and rattled down in the
woods. I saw it come down but still lost it in the leaves. It is time
to get the fishing reel in place! The tire pressure gauge I measured
with may not be accurate, it is about 25 years old.

BTW: The Orbit sprinkler valve has a manual switch function that opens
the valve with a quarter twist of the solenoid. It works so well I may
not bother to use the electrical switch. With an air compressor in my
garage it will be a while before I test it with a hand pump!

I believe there are many ways to boost this thing to more power but
keeping the 3X12 tank minimizes the air requirements (pumping) and the
24" barrel is adequate to get the job done. Initial testing leads me
to believe that this device will serve my needs!

John Ferrell W8CCW

"John Ferrell" wrote in message news Next: 55 PSI
a little more vertical... overshot the tree with lots of
clearance and passed over several others and rattled down in the
woods. I saw it come down but still lost it in the leaves. It is time
to get the fishing reel in place! The tire pressure gauge I measured
with may not be accurate, it is about 25 years old.



I found 12 volt DC would work my valve just fine. I used one of the
emergency battery boster packs to power mine.

It is usually beter to shoot from the woods to an open area if you can.

I found a open face spinning reel with some low test line on it. I did
not think it would be heavy enough to pull the line over the trees, but it
was for a very light line that I used to pull a heavy line back over with.

If you use hose clamps to hold the reel on with, clamp it to the air chamber
side. I found that if I used the barrel side the clamps restricted the
bore.

You do not need the projectile to be very tight.
I just used some electrical tape to make it fit beter. Used orange as I
though it might make it easier to find .

On Sun, 29 Nov 2009 20:11:29 -0500, "Ralph Mowery"
wrote:

You do not need the projectile to be very tight.
I just used some electrical tape to make it fit beter. Used orange as I
though it might make it easier to find .

Yech. One of the local hams was trying to use one and had the same
fit problem. Somehow, I got involved. The first thing I did was toss
a little household flour into the launch tube so I could see if the
ball was leaking. Someone appeared up with a camcorder that would do
about slow motion. Kinda like that TV show that shows things in slow
motion. The tennis ball leaked really badly.

Time to fix the leak. I decide to make a new projectile in the shape
of a Civil War Minie Ball.
http://en.wikipedia.org/wiki/Mini%C3%A9_ball
The idea was to have a conical head for improved aerodynamics and an
expanding base for a good seal. Of course, friction had to be
minimal. To improve the seal, I found some close cell urethane foam.
Using a hot nichrome wire, I cut a simple cylinder that was slightly
smaller than the bore diameter, and about the length of a beer can.
Well, it was the exact size of a beer can because that was what we
were launching nearby with a propane powered canon. Anyway, I also
used the hot wire to form a somewhat conical cavity in the base. Air
pressure would expand the base outward towards the barrel wall,
forming a better gas seal. The length of the foam would keep it from
wobbling. As long as the foam was a loose fit, there would be little
added friction. I never got around to building a conical projectile
and just dumped the tennis ball on top of the foam forming a sabot.

As I recall, we got about 60 ft with 50 lbs pressure using only the
tennis ball, and about 90 ft at 50 lbs using the foam Minie Ball.
Videos of the trajectory showed that the air resistance of the tennis
ball was only a little better than if it had been dragging a
parachute. End of flight droop was severe. A better aerodynamic
shape would certainly have been a major improvement. However, I never
tried.

It would also be fairly easy to add spin stabilization, but that would
require a one piece conical projectile.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558