First Piston cannon (full metal)

[daniel0663]

Greetings !

This is my first pneumatic cannon.
After much research on this fourm on how piston valves work etc.
(credits to "MrCrowley" and "MRR" on their helpful resouces.)

Although, the gun isn't perfect and has it's pros and cons.
I believe it works quite well.

SPEC
Vavle: 3/4" Piston vavle.
Sealing face: 3/4" hose barb With aprox 10mm Port.
Piston: 3/4" bondo mold piston or known as ( "car filler" in NZ & AUS. ) With Multiple layers of Inner tire tube and Theraband(GOLD) as Sealing face.
Air chamer: 20 x 500 x 2 Galvanzied Steel.
Fill: Schrader valve.
Pilot vavle: 1/2" Steel ball valve.
Operating pressure: 10PSI - 100PSI.
Barrel: 20 x 800 x 1 Aluminium barrel, 11 x 1000 x 1 Aluminium barrel.

Pro's
Quite powerful.
Quick fill ( 1pump = 20psi on track pump)
Changeable barrels ( thanks to "MRR" piston vavle tutorial )
Shoulder lanched. ( comfortable )

Con's
Limited power because of Small hose barb diameter(10mm approx.)
Small air chamber.
Small leak somewhere drops 13PSI in about 2mins.( i believe its the thread tape i used.)
I dont know the pressure limit on the fittings so im sticking with 100psi.


Anyway heres the pictures of the gun
Hope you enjoy them

After much research again..... I hope i can build a Hybrid cannon
And a Fridge compressor soon.
Thanks for looking
daniel0663.

[Gun Freak]

Your links are broken, so we can't view the pictures. It sounds pretty good though. Try to post your pictures again.

[jrrdw]

If you want to embed pictures into your post you need to post with the direct link that Photobucket provides not the URL. It's a easy mistake to make.

Welcome to Spudfiles.

[daniel0663]

@Gun Freak Hopefully i fixed the links.
Thanks.

[daniel0663]

@jrrdw Thanks for the advice, i have now reuploaded the pics.

And it's good to be here.
Thanks.

[Gun Freak]

In that case, not bad! It looks pretty good, except for the big pilot volume, but that is to be expected when one follows MRR's tutorial Tons of people use that design, and it works, but it can be optimised. Still, not bad.

[Mr. Potato Head]

Nice! Keep up the good work and good luck with the hybrid

[daniel0663]

@Gun Freak Thanks for the Nice compliments
Yes, there WILL be future improvments starting with the
Sealing face port...
Yes, i am aware that the pilot vavle is large, but when i had the blowgun connected to the gun it didn't give as much "recoil" as the ball valve...
I very much enjoy the "recoil" feeling.

@Mr. Potato Head Thanks !

[MrCrowley]

Looking good for a first piston cannon. You should be able to take it up to a few hundred PSI without too much worry.

Finally another Kiwi, hope you stick around. Where abouts in NZ are you? I'm up in Auckland. If you have any questions about spudgun stuff, just PM me. It can be quite a pain to find certain materials for reasonable prices.

edit:

Yes, i am aware that the pilot vavle is large, but when i had the blowgun connected to the gun it didn't give as much "recoil" as the ball valve

That probably means the ball valve is venting the pilot faster and opening the piston quicker than a blowgun. A blowgun might not work as well if the pilot volume is too large for it to vent and/or the piston isn't tight enough inside the piston housing (allowing air to escape around it and re-fill the pilot volume as it is being vented).

credits to "McCrowley"

BTW, it's MrCrowley
Don't worry about it though, there are still members on this forum who've been here for years who call me 'McCrowley'

[metalmeltr]

While the perfect picture is ther can someone give me a quick mic reading run though?

[jackssmirkingrevenge]

Excellent stuff for a first cannon, it's great to see you sought good advice before putting it together. As you noted there's room for improvement but it puts most "my first pneumatic cannon" threads to shame

Don't worry about it though, there are still members on this forum who've been here for years who call me 'McCrowley'

I thought the McCrowley was a wafer thin beef patty wedged between two halves of golf ball?

[Gippeto]

While the perfect picture is ther can someone give me a quick mic reading run though?

Here ya go....

http://www.wisc-online.com/Objects/View ... ID=MTL1902

[daniel0663]

@MrCrowley ahh, yeah that was what i was thinking about the ball valve
and also seems that the ball valve opens the piston faster.
you can also hear it opening faster.
Blowgun is like pppsstttPOWW
Ball valve is like psPOWW

Yeah, im up at Auckland also, im in Northshore.

Good to know my idol was a NZ'er

Lol.. Sorry about that "typo" error hehehe....

Thanks.

[metalmeltr]

thanks let see how i did, is that ball .825"?

[MrCrowley]

Yeah, im up at Auckland also, im in Northshore.

Haha same here, Devonport to be precise.

Are you planning on building a hybrid next? They're not great to have in suburbs, some how my neighbours seem to put up with the noise if I don't fire it too often. Though, they're a lot of fun and definitely exciting to shoot.