DWV Barrel?

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frigaardj
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Fri Jan 06, 2012 7:24 pm

I live in Australia and have been considering making a tennis ball launcher for a while. Tennis ball bore is 65mm (2.5inch) SCH40.
When I went to Bunnings and Mitre 10 today (good hardware stores) neither of them had any 65mm pressure rated (in australia 65mm is a weird size to stock). They only had it in DWV.

I would presume that there is little pressure on the actual barrel as the force can be released on the tennis ball... and therefore a DWV barrel would be acceptable. Is this true?

Thanks
evanmcorleytv
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Fri Jan 06, 2012 7:43 pm

frigaardj wrote:I live in Australia and have been considering making a tennis ball launcher for a while. Tennis ball bore is 65mm (2.5inch) SCH40.
When I went to Bunnings and Mitre 10 today (good hardware stores) neither of them had any 65mm pressure rated (in australia 65mm is a weird size to stock). They only had it in DWV.

I would presume that there is little pressure on the actual barrel as the force can be released on the tennis ball... and therefore a DWV barrel would be acceptable. Is this true?

Thanks
It's still not safe. I would sleeve it if I were you.
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Fri Jan 06, 2012 7:58 pm

Is it ABS or PVC? If its ABS its fine. PVC is too brittle to use in the DWV form.
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frigaardj
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Fri Jan 06, 2012 8:19 pm

Moonbogg wrote:Is it ABS or PVC?.
Sorry, its PVC (again, can't get ABS in Oz)
I would sleeve it if I were you.
I would have to sleeve it in another diamter of DWV, once again Australia is limited on big diameter pressure rated PVC.
evanmcorleytv
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Fri Jan 06, 2012 8:21 pm

frigaardj wrote:
Moonbogg wrote:Is it ABS or PVC?.
Sorry, its PVC (again, can't get ABS in Oz)
I would sleeve it if I were you.
I would have to sleeve it in another diamter of DWV, once again Australia is limited on big diameter pressure rated PVC.
That should be ok.
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Fri Jan 06, 2012 8:34 pm

I doubt you'll find the perfect size to sleeve it with, but it's worth a look...
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MrCrowley
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Fri Jan 06, 2012 8:54 pm

As long as it's DWV (should be 2-3mm thick) and not PVC spouting (the really thin stuff used as guttering on houses), it should be fine. Though I doubt that 65mm DWV would fit a tennis ball, I bought 65mm pressure rated PVC from Reece's plumbing (you have them in Aussie) for my TB barrel but bring a tennis ball with you to make sure it fits (not all tennis balls are the same diameter by the way).
can't get ABS in Oz
You can, just hard to find. I found a place in NZ that sells it and they get their stuff from Aussie.
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frigaardj
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Fri Jan 06, 2012 9:13 pm

MrCrowley wrote:As long as it's DWV (should be 2-3mm thick) and not PVC spouting (the really thin stuff used as guttering on houses), it should be fine. Though I doubt that 65mm DWV would fit a tennis ball, I bought 65mm pressure rated PVC from Reece's plumbing (you have them in Aussie) for my TB barrel but bring a tennis ball with you to make sure it fits (not all tennis balls are the same diameter by the way).

You can, just hard to find. I found a place in NZ that sells it and they get their stuff from Aussie.
Thanks for that info! I'll try and find some.

On the topic of Oz/NZ, do you know where to find a cheap propane regulator? I have looked in all the hardware stores, small ads, ebay etc...
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Fri Jan 06, 2012 9:17 pm

On the topic of Oz/NZ, do you know where to find a cheap propane regulator? I have looked in all the hardware stores, small ads, ebay etc...
I think most propane regulators are flow regulators or needle valves, while they could be used in conjunction with a pressure gauge on your meter, you could just use a normal air regulator.

They look similar to some flow regulators but have a gauge on them and instead of limiting the flow they, obviously, limit the pressure. Cheap ones can be had on eBay, they wont be incredibly accurate and may be made of a cheap metal that can crack easily from over-tightening but generally they work alright.

If you have a flow regulator laying around, I would suggest using that and buying a cheap pressure gauge unless you're worried about ROF (rate of fire) and want to have a pressure regulator that you can leave set to the desired pressure so you don't have to fiddle with valves or keeping an eye on gauges.

You could also try www.trademe.co.nz, most people will ship to Aussie.
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frigaardj
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Fri Jan 06, 2012 9:22 pm

Yeah, generally propane regulators seem to be designed for barbeques and similar things. I have a few lying around but they are all fixed pressure and release it at around 0.03bar.

I will try and buy and air one on eBay- do they have fittings appropriate for a typical blowtorch canister/ Burnzomatic canister?

Once again, thanks for the help!

EDIT: they all seem to be coming from HK.. :/
Last edited by frigaardj on Fri Jan 06, 2012 9:28 pm, edited 1 time in total.
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Fri Jan 06, 2012 9:27 pm

frigaardj wrote:do they have fittings appropriate for a typical blowtorch canister/ Burnzomatic canister?
No, you'll have to buy a propane bottle that comes with a torch like this. You can buy special adapters that have the propane bottle threads to 1/4" NPT threads but you wont find them in-store, probably only online (for about $12USD).

If you get a propane torch, there are a number of ways you can modify them. The easiest and most common way is to hack off the torch neck about 1" above where it threads on to the bottle and sleeve a 1/4" LPG hose over that with a hose clamp to tighten the hose on. Then you can use a hose barb on the other end that has 1/4" threads.

You could also hack of the torch and tap your own threads or epoxy threads on. There are several how-to's on the forum in the How-To section that you could search for if you need help.
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frigaardj
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Sat Jan 07, 2012 7:52 am

Today I went out and managed to find a propane torchhead at a reasonable price, finally.

You suggest that I cut it off before the pinhole, as the pressure issue from that is not great enough?

I am off to Reece's plumbing on Monday (closed today) and will but all my PVC then. Do they sell on small scales (seems to be a tradies store mostly)?
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Crna Legija
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Sat Jan 07, 2012 8:02 am

frigaardj wrote:I am off to Reece's plumbing on Monday (closed today) and will but all my PVC then. Do they sell on small scales (seems to be a tradies store mostly)?
In my experiences yeah they do but you have too pay per cut its only like 1 buck.

where in ozland are you? I'm in Melbourne
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frigaardj
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Sat Jan 07, 2012 8:16 am

Crna Legija wrote:where in ozland are you? I'm in Melbourne
Adelaide, so even less supply for stuff. Any tips on where you have bought bits and pieces?

PS we should probably start an Aussie discussion/reference thread, we have drifted from the title
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Crna Legija
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Sat Jan 07, 2012 8:33 am

i get most off my stuff off ebay or from work, so im not much help.

There is already a thread like that ill look for it.

edit, hear it is
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