My Copper SPCgH

Homemade water gun threads that are notable.
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joannaardway
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My Copper SPCgH

Post by joannaardway » Wed Jun 21, 2006 8:40 pm

Regrettably my hosting is rather like an XP-backfire. In other words, it's next to useless. Thus there are no pictures yet.

I would move to another hosting, but I want to be able to access it from school, and many hosts are blocked.

On to topic:

I've called this a SPCgH. (Semi Precharger Homemade). It's not a full PCg soaker, but it's got a bike valve to charge it up with air if I want to.

Vertigo, as I have named it, is more or less entirely copper.

As for why I have called it Vertigo:
My original plans were more or less the other way up, with a pipe running all the way down a chamber that was under the "barrel", however, shortages of pipe changed that, so it was inverted - hence Vertigo.

The pump is odd, but time is short so I'll have to explain that some other time.

The nozzles are drilled into brass compression endcaps. They're kept finger tight.

I've only got one endcap drilled so far - I wanted to check performance before I drilled any more. It's 1/8" in size, and range is around 45 feet. The lamination could be better, it's a start. Rating not yet known.

However, it has two riot blasts - a 1/2" bore one, which is actually too well laminated to really call a riot blast. Estimated at 30x
And a 3/4" one - estimated at a full 50x to 60x.

Sorry, but I have to go now. So this post has been cut short.
"Over the hills and far away, she prays he will return one day. As sure as the rivers reach the seas, back in his arms again she'll be." - Over the Hills and far away, Gary Moore

"So many people have come and gone, their faces fade as the years go by. Yet I still recall as I wander on, as clear as the sun in the summer sky" - More than a feeling, Boston

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SSCBen
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Post by SSCBen » Thu Jun 22, 2006 12:40 am

Sounds good. Email me the pictures and I can host them: ben at sscentral.org

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joannaardway
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Post by joannaardway » Thu Jun 22, 2006 9:10 am

I'll email the pictures later - they're at home and I'm not.

To finish talking about the pump, you may or may not remember silentguy's displacement pump concept.

My first attempt at a standard pump showed one thing - the shaft wasn't really strong enough, so I looked for a stronger shaft.

The old pump shaft from my old XP 110 fitted fine, but I couldn't actually find a seal that would fit as normal.

However an o-ring fitted as part of the pipe was fine.

After finding a way to permanantly fix an O-ring to the inside of a pipe, I found that the displacement pump was working fine. It needs a little work to fix a minor leak, but it's more than capable of pumping the water.

It's got 2 1-litre bottles for chambers, so the PC capacity is around 1.5 L with a light precharge.
"Over the hills and far away, she prays he will return one day. As sure as the rivers reach the seas, back in his arms again she'll be." - Over the Hills and far away, Gary Moore

"So many people have come and gone, their faces fade as the years go by. Yet I still recall as I wander on, as clear as the sun in the summer sky" - More than a feeling, Boston

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Silence
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Post by Silence » Thu Jun 22, 2006 7:32 pm

Sounds very nice--and it looks like you integrated all these radical ideas that probably wouldn't have survived otherwise. I, for one, never thought the displacement pump would get anywhere. Also, I like the way you manage to get semi-PreCharge effects (I didn't know what the "S" in "SPCgH" was yesterday, but now I do) using a bike pump. It's like pumping air with a stock soaker, and some of the pressure will probably be lost after the shot, but if you pump air like that into an already-filled PC you'd probably get a ton of power. Actually, it sounds a lot like what SuperCannon II was supposed to be.

How did you fix the O-ring to the inside of your tube? I had suggested a method in the "Two-Stroke Pump" thread, but it is probably more complicated (as is a full-blown PCgH). Well, anyway, because yours is an SPCgH, I guess I do have a shot at being the first to build a PCgH, correct? Congratulations on this one, though.

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joannaardway
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Post by joannaardway » Fri Jun 23, 2006 1:08 pm

Sure, you have a chance to be the first - unless there's someone I don't know about. I don't want to stop you taking that honour.

The pump is not exactly as you suggested, but it's not quite standard.

The check valves are both at the same end of the chamber, but the seal is stationary whereas the pump moves - "displacing" the water rather than "forcing" it.

I'll show some pictures of the sealing method I've used.
I'm removing it anyway to improve it, so I'll take some pictures then.
The components may be a little hard to find, it just happened I had the right parts lying around.

Given I have now found a way of fixing an O-ring where it is needed, many old ideas could possibly be recovered.

With regards to the SPCgH nature - It's just easier to add air pressure via a bike pump than a soaker pump, and had a spare bike valve lying around, so took advantage of this.
"Over the hills and far away, she prays he will return one day. As sure as the rivers reach the seas, back in his arms again she'll be." - Over the Hills and far away, Gary Moore

"So many people have come and gone, their faces fade as the years go by. Yet I still recall as I wander on, as clear as the sun in the summer sky" - More than a feeling, Boston

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Silence
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Post by Silence » Fri Jun 23, 2006 6:56 pm

I don't really care about who builds the first PCgH--there have been many other designs (and not even BBT/SS-inspired ones), and there hasn't been a big deal about them--and for good reason. I understand why you'd want to use a bike pump for this as opposed to a more "conventional" method, and why I might do the same: when I build my PCgH, I'll likely need a male adapter on the gun; and for the PreCharging device, I'll need a female adapter, two check valves, a tee, and all the stuff for a new pump--and this doesn't even include what's required in both versions. The other version will only need a Schrader valve and a bike pump, which I might use for a potential WBL anyway. BBT used a PreCharger button that basically transfers which chamber is being pumped to and whether air or water is being pumped; but it is complex, mixes the air and water now and then, and makes the gun at least twice as heavy as the comparable XP 270.

I think I understand the way you did your pump--however, are both check valves in the front, or are they both in the back? If you just did this because you couldn't do it the standard way, then the valves must be in the back like normal, but you can never be sure...

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joannaardway
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Post by joannaardway » Fri Jun 23, 2006 9:14 pm

It's more or less a standard pump design, the only reason it's done like this is because a standard pump design went wrong.

Assume that it's no more than a standard pump with a different seal.
"Over the hills and far away, she prays he will return one day. As sure as the rivers reach the seas, back in his arms again she'll be." - Over the Hills and far away, Gary Moore

"So many people have come and gone, their faces fade as the years go by. Yet I still recall as I wander on, as clear as the sun in the summer sky" - More than a feeling, Boston

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joannaardway
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Post by joannaardway » Tue Jul 04, 2006 8:15 pm

Finally: A picture:

http://www.freewebs.com/joannaardway/DCP00837.JPG

Any comments are appreciated.
"Over the hills and far away, she prays he will return one day. As sure as the rivers reach the seas, back in his arms again she'll be." - Over the Hills and far away, Gary Moore

"So many people have come and gone, their faces fade as the years go by. Yet I still recall as I wander on, as clear as the sun in the summer sky" - More than a feeling, Boston

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Silence
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Post by Silence » Tue Jul 04, 2006 9:10 pm

Hmm...is the pump somewhere in that back/bottom part, possibly being tracked? It's hard to tell...

I can clearly see the Schrader valve attachment, though. It's a nice gun, and while it's a bit--

Okay, just ignore everything I said above! I can see it clearly now; the pump is on top and cuts in front of the barrel-PC connections, so it looks like it actually connects in those places. What I thought was the Schrader valve attachment might be the pump handle after all, and the attachment is the metal piece underneath. Sorry about that.

The only major problem I can see with this design is that the air you pump in through the Schrader valve might get trapped underneath instead of floating to the top of the PCs. While having the pump rotated to be on top makes pumping more difficult, it does help reduce the height of the soaker--pretty brilliant for those priorities. Also, you can put the second check valve in the vertical stretch of tubing to decrease the length significantly and allow the PC weight to move back along the soaker and towards your firing hand. Everything else looks good.

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joannaardway
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Post by joannaardway » Wed Jul 05, 2006 12:43 pm

That's a presta valve - not schrader. No big problem though.

I prefer them because they are always threaded.

That's a slightly old image. The current build has a different seal on the pump - incredibly water tight.

The pump "shaft" is run along the left side of the PC to piping connection.

I could have arranged the check valves vertically, but this is my preference. It's the same length as my 27K, so no problems there.

I actually grip it via the front T piece, wrapping my forefinger around above the horizontal, a finger in of the bike valve, two behind it, and my thumb around the back. So the grip is fine.

The backpack mod I have for my CPS 3200 backpack means that I can attach it via the connector on the back - So I have lots of capacity.
"Over the hills and far away, she prays he will return one day. As sure as the rivers reach the seas, back in his arms again she'll be." - Over the Hills and far away, Gary Moore

"So many people have come and gone, their faces fade as the years go by. Yet I still recall as I wander on, as clear as the sun in the summer sky" - More than a feeling, Boston

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