Using different actuator for pneumag...

[vivalamexico]

So im building a pneumag and im thinking about using THIS mini free mount actuator from SMC. Its 13mm wide and should slide perfectly in the top slot of my logic UMF frame with no milling require. Then it could be solidly held in place with screws because the unit has side through-holes. the only milling would be drilling small holes in the frame for the screws to go through...

My question is will a 4mm stroke be enough to actuate the sear properly or should I go for the 6 mm one? I know that the electrician says 3/16 of an inch (4.75 mm) is plenty.. but I wonder if that .75mm makes any difference.. thoughts?

[Pneumagger]

get the spring return 10mm bore, 6mm stroke.

It has the same (roughly) piston diameter as the MPA-3
You will need more than 4mm, and you will still have to put gaps between the piston and sear yet too - get the 6mm, cut doen if needed.
and the air ports utthe bottom, and the piston is already stainless. all the work on the piston is done for us!

Wnat is the price on these...when you orderself one, PM me and I'll pay you for a second.

[vivalamexico]

well heres the thing SMC makes a version of these with a clevis threaded onto a male threaded rod... Im figuring the 8mm bore diameter 6mm stroke with a clevis end rod would suit our needs perfectly with almost no wear... they are 27 dollars and some change in the places where I have found them...

[Pneumagger]

the 10mm should give lower operating pressures and is closer to the .375 of the clippard MPA-3. You want to keep the pressures lower for the sake of the 3 way.

Clevis end could be promising, but then you would have to mount the piston on a pin or pivot point. As the sear rotates anstead of just translating, you will need one more degree of freedom fom the piston's mount. It's a basic 3 arm linkage.

[FinchMan]

now this is interesting. I'll just wait for AirSoldier to stock these ones now.

[robnix]

It has the same (roughly) piston diameter as the MPA-3
You will need more than 4mm, and you will still have to put gaps between the piston and sear yet too - get the 6mm, cut doen if needed.
and the air ports utthe bottom, and the piston is already stainless. all the work on the piston is done for us!

Wnat is the price on these...when you orderself one, PM me and I'll pay you for a second.

If this is it, it's about $30.00.

http://www.poweraire.com/displayitem.php?keyword=10-CUJB6-6D

Edit, I think we want the one (CUJB6-6SM) that's the spring return, which I haven't found yet.

[Pneumagger]

You don't necessarily need spring return with a QEV.

[chettacheez]

Clevis end could be promising, but then you would have to mount the piston on a pin or pivot point. As the sear rotates anstead of just translating, you will need one more degree of freedom fom the piston's mount. It's a basic 3 arm linkage.

Correct me if I'm wrong but couldn't you pivot by just mounting by using the 2 far holes, not all 4.

[Pneumagger]

you would have to reliably mount it on one axis. Not terribly difficult, but reliability would be a major concern of mine. It could be done...but when all is said and done, it's probably easier to have luke widen a frame for $15 and use the venerable MPA-3.

But any new pneumatics could open many avenues for us.

[BigEvil]

I love all of you guys.. and not just because I have a few beers in me

SOme things to consider... and im not the one to be looking at numbers rightnow... but what is the actuating force, and what is the max input pressure (in psi) that somethign like this can take?

I see there is a double acting one.. that would work great with my Electro frame.. and maybe help some of the pneumag guys with shortstroking...

[Pneumagger]

don't worry... I gave all the numbers a good look and the flow rates a quick skim. the spring return one looks better htan an MPA-3, but I'm not sure the slight increase it offers is worth the hassle of mounting it until I can get some looks tinkering with it.

[vivalamexico]

I am absolutely getting one as the cujb8-6sm will slide into a logic frame perfectly... drill two holes straight through the frame for mounting screws, clevis end to cope with translating linear motion into rotational.. all that in a tiny, quality SMC piece... Im getting one and Ill get back to everyone on how well it goes..

ack.. looking back on a previous post I see you mentioned the 10mm (3/8") bore diameter version... the only problem is that has a larger overall width and doesnt fit in the frame simply by sliding in... the slot in the top of a UMF frame is 13mm.. perfect for the 6mm and 8mm bore sizes but the 10mm is too big. The power factor on the 8mm is plenty enough to actuate the sear at 50 to 80 psi if you are using an RT or Emag on/off... and definitely enough for a ULT..

[wjr]

On the subject of using diffetant actuators... has anyone though of using this one from clippard? It was used in an electro-pneu conversion, but never in a pneumag i don;t think.
Its not as wide as an mpa-3 and you wouldn't have to worry about using a riv-nut or one of lukes pistons.

[Pneumagger]

you know, you can stick with the $10 clippard actuator. It will fit in a logic frame. I got one in my Logic Vert frame and it works great.

[the electrician]

the reason I originally used the clippard MPA-3 was price and availbility. it was cheap and I could get one easily. I had the means to modify it to what I wanted. but there are several different, more expensive options out there for those without the ability ofr know how to modify parts.

I can't recommend using anything with a smaller bore than the MPA-3. they end up needing higher pressure and limit your overhead.

and since a 4mm stroke would only be .157", less than 3/16 (.187") then I definitely don't reccomend using anyhting with that short of a stroke.


if I were choosing one of the SMC models it would have to be the 10mm bore, 6mm stroke.

but now days I make my own parts.