high flow on/off for pneu-electro-mags

[the electrician]

I had been studying the classic valve again. since I have made it into an electro-mag using a solenoidvalve to feed the mpa-3, it is easier to study changes I make to the valve for better performance.

the first thing I noticed was that there is a restriction in the air passage between the inside of the reg and the on/off hole. it looks like it is a large hole from the reg side, but with a flashlight you can see that down inside, right before it makes its way to the on/off, the passage is restricted in size. the restricted orfice is about .104"
this is smaller than the diameter of the on/off pin, which is .116" doesn't seem like much, but when air is trying to come from a reg that is being fed 800 psi, a little bit is alot when it comes to orfice size. I carefully ported out theis passage to be a minimum of .116" at the restricted point. I did this by going one number bit at a time, only taking a few thousandths at a time. going too far with this passage is dangerous., you could end up with an expensive papaer wieght if you break through the outside of the valve.

thi made a difference of about 7 msec on the recharge time. I went from a max bps of 16 up to 18, with the improved recharge rate.


this all got me to thinking about the overall orfices through the valve and the fact that the reg itself is not what restricts the recharge rate of the classic valve.

I realized this before, but now I wanted to prove it. my electromag design uses a solenoid valve to control air going to a MPA-3( the original thread for it: here) which is being used as an actuator. the MPA-3 can generate 11 lbs of force at 100 psi, which is about the max psi I can give the solenoid valve I am using. that is alot of force. way more than needed to move the .116" dia. on/off pin.

so what you say? so, I could make a large diameter on/off pin that would allow more flow IF I also ported the rest of the valve to the same new size. then, if my recharge rate improved some more, I would know that it is not the reg the restricts the rechrge rate of the classic valve.

this takes a bit of thinking to come up with a size the will be worth making, and coincide with o-ring sizes. a total redo of the on/off is not really what I want to do. I took some time and came up with two o-rings that fit together, one inside the other, just like the stock ones, and that will provide for improved flow.

the new on/off pin size is now .145" when calculated out , it provides about 1.7 times the flow of a .116" orfice at the same pressure.

this pin was a pain in the *** to make, as with every time I try to improve the automag, I gain more respect for the original design.

then I modified the on/off. I have been using an RT on/off because of it's ease of being shimmed like the ULT can be, and the two stage pin reduce the INITIAL needed force to push the sear. I emphasize intial for reason i will discuss later.

the top of the RT on/off top was drilled out to .207" this is too let the same surface area of flow, be around the new .145" dia. on/off pin. the the four side holes were drilled out to .145" also.

now last but definitely not least, the vlave body was ported out in three places. first the air passage I already did, from inside the reg to the on/off hole. then inside the on/off hole, right where the air enters at the top. and also from the on/off to the dump chamber. all of these were ported out to .145" to match the size of the new on/off pin.


I gassed it up and found no leaks. so far I have been able to reduce the recharge another 10 msec.

more testing needs to be done and some paint run through it. the problem is I'm going to have to mod the halo again to be able to feed it fast enough. one thing I'm thinking of trying is to increase the dwell time of the solenoid, instead of decreasing the overall cycle time. that would reduce the recharge time and test the recharge capabilities without testing the feeding capabilities of the halo.


I will post more, with some pics and hopefully, eventually, some video of this classic valve electromag shooting really fast.

[Bossman]

Wow! I've been waiting for this for awhile. Great work E.
I'm shooting a classic valve. It's been through a pneumatic mod, then a simple spin off of the electro-pneumatic mod. All kinds of chuffing problems with the gun trying to keep up. Had to take out the level X to get it to cycle at a decent rate. Can't wait to try some of your new mods.
Again....great work!

[tae]

Good show, man!

It has me wondering though. What is the reason for these restrictions?

[Bossman]

Good show, man!

It has me wondering though. What is the reason for these restrictions?

Keep in mind were dealing with guns that were meant to be mechanical. I'm sure that AGD never dreamed people would be making there 6 BPS markers do 20!

[the electrician]

I think, but not sure, that the reason was safety. that's why the valve is all steel and able to with stand 3000 psi. nothing is these days. nothing is a s safe as an automag as far as overpressurizing goes.

but really the only place that it was actually smaller than the original on/off pin was the .104" between the reg and the on/off hole. the other areas were at about .128" which is larger than the original on/off pin.

I've ported it out, so the metal is thinner at the top of the valve between the reg and the on/off. if you study the valve, you'll see what I mean. I don't believe there will be a problem as long as I keep it to 800 psi input.

bossman, if you have problems, you should PM me, we might be able to figure out why without anything as experimental as this.

[BigEvil]

Hey E,

Take the on/off out, the powertube apart, and shine a light into the on/off hole while looking down the power tube. See that little tiny hole that leads to the on/off chamber? Small eh?

We did a mod once involving opening that hole and the one that leads from the reg to the on/off. I also tapped a 1/8 hole above the on/off chamber and added a 'reservior' to the on/off chamber. This was going back a few years and I dont remember the specs.... There really wasnt an acurate way to test it but man did it LOOK like it made a major improvment!! We did it on an valve that the power tube could just be unscrewed. Once we saw that AGD was welding them in place we never tried another.

[the electrician]

like I said that is one of the holes I ported out. it starts out at .128" I took it out to .145" because that is the size of the new on/off pin and it wouldn't really do alot of good to make it much bigger.

I'm guesiing any results you saw were from opening the other hole, the one that goes from the reg to the on/off.

adding a resevoir to the top of the on/off chamber goes along the same lines as using an inline reg and "gutting" the stock reg. all that really does is make a chamber of already regulated air available to go into the dump chamber. I'm not sure how much , if any improvement that it makes. that would be a whole other study.

what's great about using a programmable circuit board with full auto available is the ability to test these changes and actaully have recordable results. back before, all you could do is guess.

[BigEvil]

what's great about using a programmable circuit board with full auto available is the ability to test these changes and actaully have recordable results. back before, all you could do is guess.

Have you been able to get you hands on ANY type of boards? (Morlocks, Pred2's, ect?) I finally had to settle for a TAG NME board for the project that we disscusses a while back. Ive been waiting for KM2 to ship me a Mini-Morlock for over 2 months now.

[the electrician]

you know, Ydna, who is a great businessman and quite a knowledgeable fellow is working on making his own line of really small and fairly affordable circuit boards. I don't know when they willbe available though.

but for tight now, you could buy a t-board for an ion for about $60 (if you don't need or want the ion solenoidvalve) and I can't think of a reason why it wouldn't work for an electropneumag.

I know guys are making electropneu mags using the ion board and solenoid but personally, don't like the solenoid. it uses alot of juice and I don't like the plastic barb.you just don't need that much flow. size and energy consumption wise, a solenoid like the one I'm using is better for the application.

[BigEvil]

you know, Ydna, who is a great businessman and quite a knowledgeable fellow is working on making his own line of really small and fairly affordable circuit boards. I don't know when they willbe available though.

but for tight now, you could buy a t-board for an ion for about $60 (if you don't need or want the ion solenoidvalve) and I can't think of a reason why it wouldn't work for an electropneumag.

I know guys are making electropneu mags using the ion board and solenoid but personally, don't like the solenoid. it uses alot of juice and I don't like the plastic barb.you just don't need that much flow. size and energy consumption wise, a solenoid like the one I'm using is better for the application.

Yeah I saw those that YDNA is making. I also know that a few other are working on there own as well. But since I was stuck, I went with a TAG NME board. Which really screwed up my layout and caused me a few other unforessn obsticles, but looks like will work fine now that im straightening them all out. Im putting the finishing touches on it this week and will post something hopefully by next.

[the electrician]

alright here's a pic of the modified RT on/off, the new on/off pin and it's o-rings set, then on the far right is the original on/off pin and it's o-ring set.
as you can see the new pin is a bit larger in diameter. but retains the same shape and the bottom smaller diameter is the same as the stock pin.

also the on/off itself has the top hole bored out to .207" and the side holes are the same as the pin head dia. of .145"

so far I've been able to get it to cycle with 20 msec of recharge time and not a discernable drop off in the sound signature. but I have not goldwaved it or anything. I need to get some paint through it.
I will probably test it at 16 bps, something I know it could do before just fine, but change the recharge to only 20 msec and increase the solenoid dwell time to make up the difference for 16 bps. this way I'm not testing the feed rate of the halo, just testing the recharge rate. then after I know what works, I can change it to increase the bps, and we'll see if I can get it up to the 22 bps, which is what I can get the CPS up to now.

[Bossman]

Hey E, I suppose you lathed up that on/off pin yourself?

[the electrician]

indeed, at it was a pain in the you know what. making small part , that consistent out of hard material is not easy on a manual lathe.

[Bossman]

The pin looks great though. I'm trying to put together my own little micro lathe so I can make some of my own Pneumag parts. I've reached the end of the road with over the counter pneumatic parts. I have some new Ideas for valves, but I'd have to build them myself.

[the electrician]

that's the way it is with paintball pneumatics. if it already existed, more than likely you'd know about it.

I have a 9x20 lathe and I would definitely recommend it. remember, you can make big and small parts on a big lathe, you con only make small parts on a small lathe.

I also recommend the grizzly machinery, over the harbor frieght versions. they are basically identical machines, but the quality and accessories of the grizzly are definitely better. that goes for every size.