14 replies to this topic

[cheyner]

A few weeks ago, Buffdaddy stumbled upon a ball valve that lets you change barrels on the fly, Buffdaddys write-up. Now, that particular ball valve is quite pricey at $15 apiece.
After seeing this I knew what I needed to do, make one.

You will need these materials:

- A section of CPVC
- 1, 3/4 CPVC tee
- 1, 1/2 CPVC coupler
- 1, 3/4-1/2 CPVC reducer
- Some craft foam
- Super Glue
- Dremel

First off, you are going to need to make a hole in your tee. I used a "zip" bit on my dremel to rough out the hole, then used a 5/8 drum to finish it.


Slide your reducer into the tee.


Then slide your CPVC through the hole you made, and into the inside of the reducer. Drill, or mark a hole in the middle.


Then widen the hole for better air-flow, I used the zip bit and 5/8 drum method again. This will serve as your air diverter.


Slide the CPVC back into the tee and check your fit.
It should look like this:


Then you are going to want to trim down the CPVC so there is only enough sticking out of the hole for the elbow to fit. Stick on your elbow, then mark the CPVC inside of the tee so you know where the craft foam will fit.


Pull the CPVC back out and slather some Super Glue in the space between your marks. Then wrap your craft foam around the CPVC, wait a bit for it to dry, then trim it as needed.


Stick the CPVC back into the tee, making sure the end goes into the reducer.
I put some lube on mine to make it a bit smoother, it isnt needed though.


Fill in the part of the CPVC that sticks out of the tee with some hot glue to seal it, then glue on your elbow. I put a screw in the elbow, through the CPVC just to make sure I dont twist the elbow off.


And you are done.
There are easier ways of doing this, I can think of at least 1 right now, but I thought of this first and had to follow through.
Questions? Comments?

[Fome]

Very cool. How's the seal?

[cheyner]

Very cool. How's the seal?

There is a slight leak in this one. With thicker craft foam it should not be a problem though, the stuff I use is from a dollar store, so its not of the highest quality. This is going on a Pango though, so I am not to worried about the leak on this one.

[Buffdaddy]

I love how much we've thought out stuff like this, and it seems you beat me to the punch on this iteration. Nice work! It's certainly a cheaper option than what I found (and even cheaper than the garden hose selector Y that was suggested in the other thread). I personally like the ball valve I'm using, but free samples of a $15 product would tend to skew such opinions.

Out of interest, what was the easier way you were thinking of? I have a tendency to overlook the simple things.

[ChaosRaisin]

Why not put reducers in all three sides of the tee? Or were you planning on using another size pipe than 1/2" CPVC?

[cheyner]

Buffdaddy, I have 2 more ideas floating around in my head that will be added when they are done, no spoilers.

ChaosRaisin, I only had one on hand, but one of the barrels I plan to attatch is 3/4 CPVC. The triple coupler came off of my 4B, so I figured I might as well stick it on the other end. So in the end, I could use one more, but I can do without. Three would be best for a better seal though.

[Buffdaddy]

Buffdaddy, I have 2 more ideas floating around in my head that will be added when they are done, no spoilers.

Haha, fair enough.

[Buffdaddy]

Buffdaddy, I have 2 more ideas floating around in my head that will be added when they are done, no spoilers.

Haha, fair enough.

Quick edit: My version was using 1/2" PVC and tees, with 1/2" CPVC as the selector tube. Have to bore out the PVC to make it work, but it's all good. I'm still working on the seal, though.

Edited by Buffdaddy, 06 August 2010 - 11:23 PM.

[venom213]

I really like this. It has initiated a lot of thoughts in my mind about how to do this. I particularly like it since there are so many different ways to make something like this. It's a good start!

[Buffdaddy]

I'll jot my thoughts down while they're still there (currently on short break from helping dad chop up a bunch of wood, so I'll finish this tonight. Assuming you don't beat me to it first, Cheyner).

We're making a Barrel Selector valve. Heck, I'll just call it the BS Valve, as it literally allows you to pull BS with your gun. We want it to be airtight, with little disruption in airflow, right? So we should adapt something that most decent modders can already make that's airtight. A breech.


Imagine a 1/2" PVC/CPVC breech, with the PVC bored out and all that jazz. Instead of a wide dart hole on one side of the PVC, we have air holes on either side. That gets placed in a properly drilled out 1/2" PVC tee and glued in, so that's all sealed up. You cap the end, either with an actual cap or with your method or whatever. then, the PVC between the tee and the actual blaster has the Slot carved in the PVC for your breech tab. Instead of pushing it a little around, then down the PVC, you'd have it set up so the tab is pushed down a bit, then halfway around the PVC, and back into another slot. The green scribble in the pic is the option of a small spring in there, to make it so the tab will snap back into either slot once it gets pushed into position. That way, you have an airtight 3-way valve that (theoretically) you can easily operate with just a push of your thumb.

I'll finish this example later tonight, after we finish with all this wood. Any thoughts? I figure this would be easiest, since 1/2" PVC is one of the most common barrel couplers used.

[cheyner]

Buffdaddy, that is actually pretty close to what I was thinking for Rev. 2. Maybe a bit more engineered, but pretty close.

Silverhead, it actually isnt that hard to turn, I lubed up the foam before I slid the CPVC in.
There is a decent amount of dead space with this method, but that could easily be reduced by using 3 reducers with CPVC stubs in them, cut to match the selector. I should have taken a better picture with the hotglue in it. Before it could cool, I used my finger to turn it into a ramp, so that air doesnt hit a wall at the end of the CPVC, but rather a ramp to help direct it in the right direction.

[Buffdaddy]

Buffdaddy, that is actually pretty close to what I was thinking for Rev. 2. Maybe a bit more engineered, but pretty close.

A bit more than is necessary, yes. But I think that'd work the best for my, since I'm usually holding my guns with the nondominant hand at the front of the RSCB anyway. Makes switching up my gameplay just a quick flick.

Get Rev. 2 done; this is your thread!

[Buffdaddy]

Legit double post; I updated this from the Canuck forums, as another way to make this. I know 1/2" PVC couplers are pretty standard (if there is such a thing), so this is a good alternative. In the meantime, Cheyner is using his version on a pretty awesome $hit cannon, and possibly making a better version.



I expanded 1/2" PVC's inner diameter until CPVC could relatively smoothly slide back and forth. Btw, that took about an hour to make that work. Anyhow, cut 3" or so of CPVC, with a hole on one side. Put two holes opposite each other on ~5" PVC, and cut a slot for the tab. Put a hot glue ramp in the CPVC to seal it up and direct airflow. The I took a dremeled out 1/2" PVC tee and stuck the pieces through. Sealed with hot glue and 2-part epoxy (what was handy).




I drilled a tiny hole in the CPVC, used a loose screw for the tab, and dabbed epoxy carefully to lock it in place (Not shown - placed tubing around the screw so I don't cut up my thumb). I had a spring with CPVC diameter, so I cut down a section and compressed it a bit between the CPVC and a PVC cap.

You can reference the paint drawing I posted earlier for how everything fits together.

Mind you, this is very personalized toward how I used my guns the last few wars; I switched between my RSCB and shotgun attachment quite a bit, and this lets me do it on the fly (I tend to have my spare hand on the front of the RSCB anyhow, so I can just flip my thumb). It's 100% airtight, but mainly b/c I spent so much time getting the PVC/CPVC interface perfect. Other methods of making these may be a lot faster!

[jwasko]

Other methods of making these may be a lot faster!

A set off drill bits that extend up into the 5/8" range...I find 5/8" to be a bit too small and still requires sanding for CPVC to slide though smoothly, but anything larger may be too large to be air tight. Someone will need to experiment.

The only problem is that (at least with my bit), the drill bit tends to bite into the inside of the PVC rather than drill straight through. This can be avoided/mitigated by finding PVC with a slightly larger than average inner diameter (it varies from brand to brand) or by using several drill bits to "ramp up" the inner diameter (39/64"?).

(Or maybe I just need a better bit...I got the cheapest I could)

Also, "conduit" PVC (in the electrical section of Home Depot) seems to have a slightly larger inner diameter than most Sch.40 PVC. It also seems softer than most other PVC, possibly due to its cool gray color. The softness and inner diameter combine to make it easer to drill to 5/8" ID, if you don't have slightly smaller bits that you can use to help ramp up the size.


OR you could try 1/2" thinwall PVC, and use e-tape and lube to get a good sliding seal.