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Unread postPosted: Sun Jul 22, 2012 6:18 am
Author: TheNewKid22
can someone please link me the strongest slide valve and qev combo? looking for something that will handle 800 psi?

Unread postPosted: Sun Jul 22, 2012 6:31 am
Author: Crna Legija
TheNewKid22 wrote:can someone please link me the strongest slide valve and qev combo? looking for something that will handle 800 psi?


paint ball slide valve and any euro style QEV will do, it will handle 800 but i wouldn't say is safe.

Unread postPosted: Mon Jul 23, 2012 5:13 am
Author: TheNewKid22
yeah i thought the same but has anyone tried a paintball slide? looking for a thread size but i'm thinking 1/8"?

Unread postPosted: Mon Jul 23, 2012 5:30 am
Author: jackssmirkingrevenge
They're typically 1/8" (watch out for NPT/BSP) but they have very poor flow - still, they should still pilot a typical cup/parachute style QEV adequately.

Unread postPosted: Sat Aug 11, 2012 10:08 pm
Author: MrCrowley
What does everyone think about welding a 2"x1.5" iron reducer inside a steel barrel to get 1.5" threads by either grinding down the 73mm area to match the ~68mm part or cutting it off. The inside diameter of the barrel is 68.5mm.

I'll have to grind down the lines that run vertically down the 68mm bit as well as any raised writing on the fitting.

Unread postPosted: Sat Aug 11, 2012 10:37 pm
Author: doomburger
I know that I could dye PVC with purple primer (possible weakening of the PVC though), but I have read somewhere in the forums that you could use abs pipe glue to dye the pvc black. Is this possible?? Thanks guys.

Unread postPosted: Sat Aug 11, 2012 10:49 pm
Author: Fnord
Doom burger: Yes. Don't put it on too thick. It drips a lot.

Crowley: That would work fine, but with that much surface area to work with you could solder it in yourself, if you'd otherwise have to pay to get it welded. Just make sure to grind off all the galv. Thoroughly flux and tin both parts before doing the actual joining. I made a 1.5" barrel for my old hybrid this way, and it came out pretty nice (it's shown in the thread now).

Unread postPosted: Sat Aug 11, 2012 11:41 pm
Author: MrCrowley
Thanks for the tips. I don't have any flux or solder and it seemed pretty expensive last time I saw it at the hardware store so I might just see if I can get it welded for $20-$30 like my current S/S barrel.

Unread postPosted: Sun Aug 12, 2012 8:34 am
Author: dewey-1
MrCrowley wrote:What does everyone think about welding a 2"x1.5" iron reducer inside a steel barrel to get 1.5" threads by either grinding down the 73mm area to match the ~68mm part or cutting it off. The inside diameter of the barrel is 68.5mm.


I recommend using a half coupling also known as merchant coupling.
Much easier to weld and it is steel not black iron.

The holes in barrel are for weld fills for extra support. (optional)

Unread postPosted: Sun Aug 12, 2012 1:42 pm
Author: MrCrowley
Thanks for that, I was actually wondering about drilling holes for weld fills but wasn't sure if it would do more harm than good. I think I know a place that sells those steel couplings as well, but they're only open on the weekdays so it can be a bit difficult getting out there with uni going on.

Unread postPosted: Tue Aug 14, 2012 1:02 am
Author: MrCrowley
Double post:

The pipe I ordered finally arrived, unfortunately the wall thickness is 2mm not 3.25mm, so my tennis balls (65.5mm diam.) are even a worse fit than they were originally (71mm I.D. instead of 68.5mm). I emailed the seller who told me that I was mistaken and to check again, so I replied in fashion (not sure why the picture is flipped) :D

In the auction listing, the picture does seem to show 3.25mm thick pipes so maybe they sent me the wrong stuff. If not, I might just have to make do as I didn't see any other sellers listing similar pipe per metre. I could always turn it in to a hybrid chamber but the 2mm wall thickness seems a bit low for 10x mixes.

Unread postPosted: Thu Aug 23, 2012 11:27 pm
Author: Goats spudz
Looking for some thick wall Aluminium tube for my new PCP, it needs to be able to fit a crosman 2250 valve inside it, I have narrowed it down to This The Crosman valve is about 18.6mm in diameter. Do you think this would be any good? if it leaked i could turn an internal O-ring groove

Unread postPosted: Fri Aug 24, 2012 12:17 am
Author: jackssmirkingrevenge
How were you planning on attaching it? Unless you epoxy it in place you'll need o-rngs even if it's a perfect fit.

Unread postPosted: Fri Aug 24, 2012 1:15 am
Author: Goats spudz
jackssmirkingrevenge wrote:How were you planning on attaching it? Unless you epoxy it in place you'll need o-rngs even if it's a perfect fit.
Theres a threaded hole for a mounting screw opposite the exhaust port on the valve im just gonna use an M3 CSK bolt, Machining isn't a problem as i now have weekly access to a Hurco TM10 and a VMX64T, i have a Solidworks model on my other Laptop but only have a 2min Mspaint bodge :D

Unread postPosted: Fri Aug 24, 2012 8:58 am
Author: PaperNinja
For an air cylinder type loading system for semi auto, does anyone know if the spring is to strong if it "opens" the barrel (begins loading another bb) at 80 psi?