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P.A.C. 5

Posted: Fri May 26, 2006 2:15 pm
by x.X.Cpt.Rollhart.X.x
Hi, I plan to build a P.A.C. 5 ( http://www.xinventions.com/main/spud/pac5.htm )

And i have some question about this cannon.

the person who made this cannon say :This is my fifth pressurized air cannon (P.A.C. 5) that I have made and happens to be one of the most powerful cannon I have constructed yet. At a recent test, this cannon shot potatoes over twice as far as my P.A.C. 4. Latest shot: 1,276 meters with a specially made PVC dart.

Do you think that cannon can really shot 1276 meters ???

And on the picture, what is the utility of this part ?

Image

and if you have any advice or impression on this cannon, said me :)

Posted: Fri May 26, 2006 2:24 pm
by saladtossser
i think that is the piston, made of a 3" coupling

Posted: Fri May 26, 2006 2:38 pm
by x.X.Cpt.Rollhart.X.x
saladtossser wrote:i think that is the piston, made of a 3" coupling
oh I didnt notice that it was the piston :?



and another question, As you know, I am not very good in english, and in this paragraph :Piston & Bumper Construction

1/8" Hard neoprene with cloth insert (1000PSI) was used for the diaphragm material. This material is much stronger and is actually pressure tested to withstand the extreme pressures. This material works much better and is the ideal for the diaphragm.


he talk about a diaphragm, Why ? this is a piston cannon, isnt it ?

Posted: Fri May 26, 2006 2:42 pm
by x.X.Cpt.Rollhart.X.x
And, what is this assembly utility ?

Image

why didn't he just put the barrel with the "spacer" ? there is a kind of coupler and a strange piece of pipe over the barrel ?!?!?

Posted: Fri May 26, 2006 3:03 pm
by saladtossser
it is a piston valve, he was wrong to call it a diaphram, i call it sealing face

please rephrase your second question

and dont double post, use the edit button

Posted: Fri May 26, 2006 4:18 pm
by boilingleadbath
I believe the odd peice of pipe is being used as a centering device for the barrel. I'm not sure, but I think he makes them from bushings.
I personaly just glue peices of small-diamter PVC pipe to the barrel.

Posted: Fri May 26, 2006 4:39 pm
by WOW!!
That is to keep the barrel in the center of the chamber so it doesent move around. The diafram is a sealing face on the piston.

Posted: Fri May 26, 2006 4:46 pm
by x.X.Cpt.Rollhart.X.x
WOW!! wrote:That is to keep the barrel in the center of the chamber so it doesent move around. The diafram is a sealing face on the piston.
ok thank you

Posted: Fri May 26, 2006 5:13 pm
by Benny
also, if the pipe isnt perfectly strait it wont seal, thats why they have coupleres, because there straight.

Posted: Sat May 27, 2006 7:48 am
by rna_duelers
But does any one think it can really shoot 1276 meters?(4186.3 feet)thats quite far,more then three drag strips :shock: :shock: thats far.

Posted: Sat May 27, 2006 9:33 am
by drac
I personally think he could have... but who knows. You'd have to have a saboted dart to acheive distances like that, because most projectiles are just too un-aerodynamic and heavy. I'm not sure whether he'd need Helium though.

Posted: Sat May 27, 2006 7:38 pm
by Benny
with a coaxial valve that big and a battery, he could have.

Posted: Sat May 27, 2006 8:01 pm
by x.X.Cpt.Rollhart.X.x
Benny wrote:with a coaxial valve that big and a battery, he could have.
what do you mean with by a battery ?

and Do I have to put a spring behind the piston ?

Posted: Mon May 29, 2006 3:16 am
by Benny
as the projectile.

Posted: Mon May 29, 2006 11:31 am
by x.X.Cpt.Rollhart.X.x
ok and I have another question, how many inch sould I put behind the piston ?