BW Classic Valve Reg Cap

[superman]

I have been working on this awhile and yes this is the other part that is planned to go with the rail i made.
Thread milling kicked my butt but i figured it out. I ended up scraping the first one due to a funky tool path but this one came out great.

[Ecapnation]

Nice work!

[superman]

Thank you!

[Jordan]

I'm happy reg caps are being made, but what made you change your mind on 'em? You've seemed against them in past threads.

[superman]

I wouldn't say i am against it. They have their place. Do i think every valve should be swapped over no. Valves that have mismatched backs or maybe that have failing spring packs and reg pistons or the combination of all of the above make it a decent option. I do recommend running them with quality regulators that have blow offs incase of failure and that the users understand that they are soft aluminum not stainless like the original reg back.

[FredMnkyDad10]

That is awesome. Put me down for 2 at least.

[Toestr]

Cool. What if you made the cap with it's own relief valve?

[superman]

I can machine the caps to have burst disks.

[Walker]

Two for me, please...


Walker

[Grendel]

Super cool looking, I have one of Kits that I have slated for a valve but I might just have to put together another build so I can use your

[rawbutter]

That's great, especially the view from the back. Great job lining up everything just right.

The back cap that I have has a sideways hole through it so an Allen key can go in and be used for leverage to tighten it down. Any reason why you went with finger grooves instead?

[superman]

Thank you, It was very much intentional.
The big reason is i didn't want to deform the cap with the hole. I may go that route but i wanted this one to be more decorative, especially since i have been trying to develop some more skills. lastly because i was way less confident in my drilling operation in the cnc.

[MrBarraclough]

Hang on a minute, if you're going to drop the A.I.R. from a classic valve mag and use a back cap, couldn't the back cap serve as a volumizer?

Hmm, the more I think about it, I suppose the on/off closing during the firing sequence would prevent you from using the back cap to effectively increase the dump chamber volume. Too bad. I suppose at best you could use a high volume back cap as a kind of buffer between the HPR and the on/off to smooth out any recharge hiccups, but that's probably not enough of a benefit to be worth the work.

I'm still a little fascinated by the idea of somehow using the space freed up by dropping the A.I.R. as a sort of screw-on Magic Box. You'd have to drill a new air passage to link the void space in the back cap with the dump chamber, but at the same time somehow isolate that path from the incoming air supply (otherwise you'd be defeating the on/off). Damn, that would be complicated.

The one thing I wish could be changed about Automag design is the dump chamber volume, since it sets such a high floor for operating pressure.

[MrBarraclough]

superman Yeah, I would not expect post-reg but pre-on/off volume to affect velocity, since it does not change the volume of the dump chamber. A larger pos-reg volume might smooth out pressure dips and spikes as the reg recharges with each shot, but that's probably a minimal benefit. I accidentally omitted the word "not" in the last sentence of the second paragraph, which I'll edit to fix.

[MrBarraclough]

Brokeass_baller, wouldn't the force differential between the bolt spring and the dump chamber pressure simply determine the force with which the bolt pushes the ball into the breach? As for the air pressure the ball sees once the bolt "uncorks" from the power tube, shouldn't that be determined by the input pressure to the dump chamber and the increase in volume created by the bolt moving to the end of the power tube? So long as the pressure is sufficient to move the bolt forward enough to vent through the power tube, the pressure of that initial blast of air should not be affected by the spring tension.

It occurs to me that spring pressure does matter when it comes to dwell, though. The pressure in the dump chamber might not drop all the way to ambient before the spring begins to return the bolt rearward and re-plugs the power tube. A stiffer spring will overcome the escaping air pressure and start moving the bolt back faster than a softer spring would. Bolt mass would affect this as well. A heavier bolt should increase dwell (for a given spring strength), since it would have more inertia that the spring would need to overcome to reverse its travel. Likewise a lighter spring would also increase dwell, allowing the dump chamber pressure to drop closer to ambient before the bolt re-plugs the power tube. I wonder how much dump chamber pressure is actually used to propel the paintball before the bolt recloses, and if any pressure above ambient is actually retained. I know that is something the Gamma Core, for example, does deliberately, which is part of how Emeks have such great recharge rates.

[Brokeass_baller]

MrBarraclough I'm no engineer, but I have plenty of experience with rigging, machine leveling, and counter-balancing. I assume air pressure would act similarly.

To keep things simple, let's say there's always 100psi in the dump chamber before shutoff by the on/off, and the spring tension at it's heaviest, before uncorking, is a consistent 75 pounds. The moment the air pressure drops to 74 pounds, the spring would overcome it and begin to push the bolt back in to cork it. That would mean only 26 pounds of pressure escaped to actually do any work propelling the ball.

I'm sure there are some different factors that should be taken into consideration that I don't have enough knowledge about. Like air pressure decrease as it expands from the power tube tip and into a larger volume bolt, and then further decreasing as it enters the large opening of the breech/barrel. And same with back pressure affects the ball would have on it.

But I think, roughly, the force required to push the bolt forward would cancel out a lot of the air pressure behind it trying to exit the dump chamber. So, the ball wouldn't be hit with the full force of the dump chamber psi.

[superman]

I ended up flying out to San Diego this week. Wife had a conference and I had never been to San Diego. I got a little play time in today with the mag. It shot great. Need to adjust my sear rod a bit but overall super happy with it considering i put it together last week with minimal testing. I was also able to meet up with a friend i have known for a long time, but never actually met in person. noclue119

Had a blast playing at ASG and i'd recommend it if anyone is in the area.

[FredMnkyDad10]

Way cool. Glad you got to play and meet up

[superman]

So a little update. Still tweaking the programs, but these things are coming out pretty sweet. I can't wait to see one of these anodized.

[superman]

Quick throw together.

[FredMnkyDad10]

I would be down for 1 or two. Does your rail clear ule warp right or left body with any notch mill?

[superman]

The rails will require additional cuts for warp bodies. I can do it, just need to model it.

[Pump&Run]

Beautiful Sir!

[superman]

Thank you. I just wish the caps were easier to make on the mill. I think there are 7 tool changes (excluding probing), 2 mill setups and a parting op in the lathe. Which produces just 1 cap. lol

I am sure i could probably cut a couple tools out, but i am still learning so there is that too.

[superman]

I didn't run a finishing pass on the inside bore, although i should have.

[superman]

I am using flood coolant.

[nerdcore]

There were parts, that make a complete build, I was gonna try to sell you, but if you keep making new 'mag stuff I may need to actually finish the build. Why do you do this to me?

[superman]

Who said these wouldn't be sold almost complete