PVC and the UK - Metal soakers

unigamer · Post by **unigamer** » Wed Jun 07, 2006 3:13 pm

On the toolstation website there is a section for 'Plastic Compression', I was wandering what this is and whether or not it is suitable for water guns.

http://www.toolstation.com/shop/Plumbin ... d20/sd2884

I was looking at the brass pieces too, and while there are good prices you need to buy in bulk, ie 10+ at a time which is way more than I need and probably ever will need.

Silence · Post by **Silence** » Wed Jun 07, 2006 4:31 pm

I believe the "compression" refers to a piece that tightens and closes when you twist it in the appropriate direction, and loosens when you turn it the other way. The pieces appear to be couplings (both standard and special, including reducers, tees, etc.), but instead of using glue, they are temporary because they can be attached or taken off. I recently saw suggestions for using such pieces for adjustable nozzles, but people had been referring to those used in camera lenses--which would not produce a smooth stream.

insanitys_engineer · Post by **insanitys_engineer** » Wed Jun 07, 2006 11:25 pm

On the toolstation website there is a section for 'Plastic Compression', I was wandering what this is and whether or not it is suitable for water guns.
http://www.toolstation.com/shop/Plum...ion/d20/sd2884
... while there are good prices you need to buy in bulk, ie 10+ at a time which is way more than I need and probably ever will need.
Today 01:26 AM

I think the plastic ones will need glue, as with the brass ones the o-rings dig into the copper so you cant get them off = good seal. The plastic ones don't have this luxury (plastic squished against plastic, not using a malleabe o-ring, and so probably won't hold as much pressure. They are only designed for waste water from a sink, not 60psi.

With the buying in bulk, you generally need a few of each piece per weapon. Its worth spending £6 for 10 22mm connectors online , and making a couple of guns rather than spending £6 on 2 from a hardware store (probably cheaper at a plumbers, but not as cheap as online)

Mind if I repost a short summary of this water gun on our website later this summer? If you can write a more detailed article instead I'd appreciate that as well. I mainly want people to know that you can make water guns from things other than PVC, and this is one of the few water guns not made from PVC.

No problems. i'll rewrite a more detailled one, including some of the physics i considered, in the next week or so. Ill post it in here to make sure everyone agrees with it.

joannaardway · Post by **joannaardway** » Mon Jun 12, 2006 12:41 pm

Hmm, maybe I'll do this at some point. As you said - UK PVC is hard to get.

However: my local DIY stores are crazy about copper pipe. And as I already know - 1 litre drinks bottles make excellent PCs. And as a bonus 22mm copper pipe fits exactly into the neck of many plastic bottles.

Thanks for the idea.

However, with regards to PVC - you can get most things over here - if you look in the right places. Try pipestock, Koicarp.net, or Piscesaqua.

All of those do everything you might need (koi-carp is weak on check valves though)

insanitys_engineer · Post by **insanitys_engineer** » Mon Jun 12, 2006 9:40 pm

Eeeeeeeeeeeeeeeek they are expensive though! I only looked at the valves to start with, but £6 a valve is a lot. I may consider it in the future, but not for a few months ( moneys

) I'd reckon a gun to be more powerful, but way more expensive. It depends how far you want to go really i suppose. I'll post when im sober...

Silence · Post by **Silence** » Mon Jun 12, 2006 9:44 pm

I'm not sure of the exact exchange rate, but 6 pounds doesn't sound like too much for a valve. In general, it's the fittings (valves, reducers, tees, etc.) that add to the cost of a homemade--and a good homemade usually costs abut $30 USD here. If you buy PVC in 10 foot segments, it should still be relatively cheap and should last for a few different soakers.

insanitys_engineer · Post by **insanitys_engineer** » Mon Jun 12, 2006 9:52 pm

£6 is rougly equal to $10. I think it comes out as more expensive, size for size on 2" pipe alone, and with a very basic design.
For 2" designs, the valves are very expensive. You'd be hard pushed to do it for £20 ish.
gaze on the cost! https://www.pisces-aqua.co.uk/acatalog/ ... ketsy.html

Silence · Post by **Silence** » Tue Jun 13, 2006 1:18 am

Wait a minute, are we talking about ball valves, then? Clearly, a check valve does not need to be wider than the pump (so it's usually no wider than 1/2", and definitely not 2"); but 2" is still pretty wide for the barrel, and you might have some trouble just turning the valve.

insanitys_engineer · Post by **insanitys_engineer** » Tue Jun 13, 2006 9:43 am

Ok im sober now. The reason behind bigger valves is more water being pumed through. I suppose that the smaller the valves, the more pressure can be applied to the water inside and so pumping it quicker. hmm. Well anyway, the next design (next month-im broke) will at least experiment with a rotary handle for the pump.

on a different matter, does anyone know what sort of pressures you cn get in a PC? Specifically a coke bottle PC type thingy. If its not as high as 100 PSI i will have a go at an air charged one. You can get cordless compressors for £20, and this would make anyone with a gas charged gun lethal to the maxx!

joannaardway · Post by **joannaardway** » Tue Jun 13, 2006 10:04 am

I've put 100 psi into a plastic bottle. I haven't yet trusted it above this to find out where it blows.

Coke bottles can go over this, and don't blow until above 200 psi.

However, I wouldn't exceed 150 psi in a bottle if you value your face.

Your seals don't appear 100% - if you had 22 mm pipe super glued into the bottle neck, then I might trust it to 150.

I wouldn't put your soaker above 100 psi at the moment, and even then it may well explode.

The chances of the compressor being any use is about 0%. Those things have limits of about 8 bar (if you are lucky), and would take many many minutes to pressurize your soaker.

I tend to find that PVC is expensive over here. However, if you're doing it, go for Class E or 16 bar pipe. Again - if you value your body, less than this is suicide.

Koicarp is generally cheaper, but I would get your check valves from pipestock. In addition, Koi carp won't do low diameter parts.

So, yeah, copper is a good way to go. The trouble is that IDs are limited and you have to find a different thing for your chamber.

I'll attempt a copy of this, but with a 22mm ID, and using compression end caps for ease of replacement. I'm buying some copper for another pneumatic cannon soon, so I'll have a bit of 22mm left over.

I'd just need a few pounds for check valves and parts.

insanitys_engineer · Post by **insanitys_engineer** » Tue Jun 13, 2006 2:54 pm

funny you hould say about PCs being blown off: i tried a big lidded pot to replace the bottle. THe lid was connected to thr gun, and the pot on top, all glued with all purpose adhesive (god bless it). Having pumped it up I prepared to fire, only to be drenched as the PC soared off the gun , and only bounced on the house roof on the way down.

The next gun I am making will be a 22mm ID, with 15mm valves on the pump end. Not sure about the rotary pump the more I think about it. Ill also try the bottle fit onto 22mm. You nay find epoxy resin will be better than superglue as it will fill in between bottle and tube: superglue is not good for gapfilling.

This evening ill try a new PC so i can use the gun without it leaking liek a sieve.

It'd be cool if there was a way of sending the parts back out, as i don't need the bulk, and i will probably be ordering lots of stuff.

insanitys_engineer · Post by **insanitys_engineer** » Tue Jun 13, 2006 6:52 pm

A new tank is connected (thanks joanna for the 22mm/bottle idea) and I need some more adapters fo the back tank, or another 15mm valve. I reckon I got it to about 100psi, judging by the level of water in the tank.

Also, I found some springs, and drilled a new hole in the ball valve arm, and set it to stay closed. Now its easier to burst-fire, as it shuts itself when you release.

I'll post a pic once it has a casing

Silence · Post by **Silence** » Tue Jun 13, 2006 7:25 pm

You should consider setting up the gun to allow for a trigger to connect to the ball valve. That's what I'll do with my compact APH, even if I don't connect a trigger immediately; and I'd also like to see your method of securing the springs. Mine probably won't be as complicated or as functional, but it should work. Also, remember to lubricate the ball valve as much as possible, or you'll have a tough time pulling the ball valve's handle (original force + x, where x>original force and is the force of the return spring) with just one or two fingers. No matter what, though, I'll probably end up using two fingers to pull the trigger on my soaker.

insanitys_engineer · Post by **insanitys_engineer** » Tue Jun 13, 2006 8:18 pm

The trigger i intend will be a whole hand one, and as simple as a big lever. Currently its 2 expansion springs, and one is hooked on the end of the nozzle. About as scientific as a vacuum. Its not too bad pull-wise, but it sticks if i leave it for longer than an hour. its really good for burst fire though now. The extra close control is so worth it!

Silence · Post by **Silence** » Tue Jun 13, 2006 8:37 pm

insanitys_engineer wrote:About as scientific as a vacuum. Its not too bad pull-wise, but it sticks if i leave it for longer than an hour.

Normally, I'd say that skilled water warriors would be able to do tap shots anyway, but that point really strikes me as intelligent. While I haven't actually used a ball valve yet in battle, I can imagine myself leaving it open for longer than an hour--and that would be bad. I'll be sure to grease my metal ball valve and make sure I can work it like a trigger--that way, I'll have one hand on the pump and the other on the valve.