Need New Zealand Ideas

[microman171]

My coaxial needs a whole bunch of new parts and it is all solvent welded together so I would have to start again. I have decided I may as well make a completly new cannon. I need some good New Zealand Priced (Mr Crowley will tell you what I mean) ideas for my next cannon. I have a very small budget and aim to get the best balance between cost and power. I am open for suggestions (I want to try a diaphragm valve but dont really know where to begin)

EDIT: This is what I would like to make http://www.spudfiles.com/forums/diaphra ... t5049.html

[MrCrowley]

I'd recommend pistons over diaphragms, just easier considering our availability of plumbing materials.

What sized cannon would you want to build? If it's a piston valve, what size tee and what size barrel and what size chamber?

Also what is a rough estimate for your budget?

[microman171]

Well I am still at school and dont yet ahve a job. So I would set it at around $100 if at all posible. I would like to have golf ball support but It doesnt really matter. By the look of the union diphragm it would be pretty easy but I know you have been doing this longer so I'll take your word for it. If you are suggesting useing a tee then I guess 2" may be out of the question... How much are they (just a ball park). The one material I do have is cement primer and about a meter of grade F 50mm PVC. What it the price of steel and brass in NZ? That could be another posibility.


I am more interested in power rather than size (If I can get a marble to break thick plywood I think that would be cooler than a golf ball cannon that sometimes breaks thinner plywood.)

[MrCrowley]

Well breaking plywood with a marble will require high pressure, high pressure = a lot of cash.

Do you have an air compressor? If not, may as well put pistons above 20mm out of the equation. And I mean a proper air compressor, like 21litre or something. Not a 12v car one.

A 2" tee cost about $16 and an average 2" fitting will be about $12-$15 each. Brass fittings are cheapish as long as you go to a Mitre10 Mega or Bunnings. They'll be about $1-$2 each for 1/2", about $8 for 1/4" and about $3-$4 for 3/4" and 1".

Though only 1/4" nipples and air compressor fittings are usually available, you wont find any elbows or tees in stores.

If you had an air compressor you could make a powerful golfball piston valve cannon.

80cm long 50mm chamber
200cm long 40mm barrel = $35
1 50mm 90 degree elbow = $12
1 50mm tee = $16
2 50mm female adapters =$11 each ($22)
2 50-40mm bushings = $6 each ($12)
1 50-25mm threaded bushing(black hansen fitting) = $6
bunch of brass fittings = ~$30
etc etc

You can only buy pipe in 1m lengths or 6m lengths if you go to a plumbing merchant. You'll also waste 20cm of 50mm pipe on joining fittings together.

I don't think it could be done for under $100, it'd be hard. I built my latest cannon on a budget of $350-$400 and i'm only 6th form in High School with no job and no pocket money...and am not a criminal

Here's my how-to for inspiration on how I made my 2" piston and how you'll most very likely have to make your piston housing (the tee, barrel seat and female adapters).
http://www.instructables.com/id/Golfbal ... That-Shoo/


Edit: A Diaphragm valve could be done but you would be going into uncharted terriorty, i.e i'm not exactly sure how you would want to go about doing it or how much it would cost. It could be better in your case, but I would have no clue where to get a big enough piece of neoprene and I doubt the performance would be as good.

BTW my paintball/marble cannon 'Slim Biggins' snaps 3/4" wood a metre long and 7cm wide, in half from head to toe at 280psi. But it uses a QEV, which means you'd need to make a piston valve, the fittings are galv and quite big which is more cash and I spent $50 on a 260psi floor pump.

[microman171]

I have no air compressor only a bike pump (up to 100PSI I think) I still like the sound of a marble cannon even if it cant break plywood (I can also shoot darts out of it and other ammo on this forum). The only other thought I have is copper... I do have the gear to solder copper but I think that sticking to PVC would be cheaper seeing as I have no air compressor. The main criteria is NO COAXIALS. The reason for this is because I have been there done that and it wasnt that interesting. I think I will call into bunnings and buy what I need (Taurange mitre 10 MEGA is pretty hopeless at PVC). I was thinking 1.5" pressure chamber and a changeable barrel system. I also want a serviceable piston (probably just use some threaded fittings).

[MrCrowley]

You could make an alright marble sniper out of PVC for about $100.
Copper would be too expensive.

What's wrong with co-axials?

[microman171]

Nothing is wrong with them I just want to try something new. That and coaxials cant have a set of barrels as easily

[Gippeto]

How about a "Toolies" piston?

http://www.spudfiles.com/forums/valve-t ... ter,0.html

Cost to build should be somewhat reasonable as you only need a few fittings, and you can thread on the barrel or use cam-locks(barrel interchange).

[SpudFarm]

could this be something for you?
good at 500psi if you have the pump.

[MrCrowley]

Cost far too much. That's 40mm copper, no?

[microman171]

How about a "Toolies" piston?

http://www.spudfiles.com/forums/valve-t ... ter,0.html

Cost to build should be somewhat reasonable as you only need a few fittings, and you can thread on the barrel or use cam-locks(barrel interchange).

That looks GREAT! Thanks for the Idea. Just need to make the piston servicable. It looks like the price should be into my range too

[SpudFarm]

he can allways make it smaller MC

[MrCrowley]

Yeah but you can only buy copper in 6m lenghts as far as i'm aware and according to plumbing merchants. So you're looking at $150 on 6m of 20mm copper.

[microman171]

Aw. Well that certainly puts copper out of the question... I am still interested in the toolies style gun.