7 replies to this topic

[venom213]

I very much appreciated the work done by TantumBull on homemade OPRV's, but I always felt like his version wouldn't be very sturdy if adjusted a lot or used at high pressures. Here's my take.

I cut a 2 1/4" Long piece of 1/2" OD 3/8" ID PEX Tubing.



I drilled a small hole in the middle of the PEX



I cut a 1/2" Long Piece of 3/8-16 Threaded Rod.



I smoothed out the ends of the threaded rod with a file and bench grinder. I then dremeled a notch into it to make a set screw.



I tapped one end of the PEX with a 3/8-16 Tapping Bit.



I drilled into the PEX about 1.5" with a 3/8" Flat Wood Boring Bit on the opposite end.



I tapped the drilled end with a 1/8-27 NPT Tapping Bit.



I cut two pieces of vinyl tubing. One piece of 1/4" ID 3/8" OD and one of 1/8" ID 1/4"O OD tubing. Both should be around 5/8" in length.





I sanded the outside of each of the pieces of vinyl tubing a bit. I made sure that one of the ends of the 3/8" OD tubing is very flat and even. I then carefully applied Plumbers Goop using toothpicks all around the 1/4" OD tubing and inserted it into a 1/8" NPT Brass Fitting that has a barb for 1/4" OD tubing. I pushed it in as far as it could go. I than pushed the 3/8" OD tubing over the 1/4" OD tubing. I applied goop all over the 3/8" OD tubing and the Brass Fitting then pushed/threaded it into the end of the PEX that was tapped with the 1/8-27 NPT bit.





I cleaned off the excess Goop with a rag. I let that dry for 24 Hours. Once the Goop cured I inserted a 5/16" Ball Bearing, a small but strong spring, and the set screw.



The end product:



I set the pressure by adjusting the screw. I use my portable compressor set-up for this as well.



DEMONSTRATION VIDEO

Edited by venom213, 20 February 2011 - 02:43 PM.

[WicketTheModder619]

First a homemade pump, now a homemade check valve....this has homemade airgun written all over it. Anyway, major props man, you ever been cranking some pretty cool stuff out lately. Keep up the great work!

[ahtanie]

Wow that's very impressive. I like it a lot!
Good work venom!

[kidame tomanaka]

now we the people of the community have a home made pump, oprv valve, and the homemade air tank, we now have the parts for a fully home made air blaster.

Edited by kidame tomanaka, 20 February 2011 - 06:41 PM.

[ricochet]

I love this, great work. You posted this just in time, right before my first airgun build. Can you get the tapping bits and ball bearings at a hardware store, or do I need to order from mcmaster?

[venom213]

I love this, great work. You posted this just in time, right before my first airgun build. Can you get the tapping bits and ball bearings at a hardware store, or do I need to order from mcmaster?

I got everything I used locally at Ace/The Home Depot. You might be able to get away without using tapping bits if you drill the PEX right. I got the taps because I knew I'd build many of these.

Edited by venom213, 20 February 2011 - 10:59 PM.

[TantumBull]

This is awesome, I love it. Sooo superior to my shitty pen threads, haha. One thing I've noticed with these is that they can be temperamental if hooked up to constant pressure (ie the main firing tank). I think this is why Hasbro puts them in the pump heads, as they won't siphon off the tank's air over a period of time. I've found them much more effective when installed in pump tubes/on pump heads. What's your experience with this issue?

[venom213]

Tantum: I haven't implemented one of these into a system yet. This weekend's mod party should yield some results. I'll keep this updated with future testing.

Edited by venom213, 23 February 2011 - 07:38 PM.