SpudFiles

More just a thirst for knowledge question here..

whats the largest hammer valve you can make that is still effective? With BTB's new counterbalanced hammer valve and not needing a super strong spring, i'm curious how a hammer valve would perform with a barrel of 1" or 1.25"? Obviously it wouldn't be as efficient as a burst disc say, but I'm just curious.

As long as the hammer grows with the valve, you can go as big as you like.

One thing to keep in mind, larger calibre launchers normall use lower pressures - imagine a commercial PCP airgun with a 3000 psi reservoir and a 0.2" valve diameter, that's a force of 94 lbs the hammer has to overcome.

Using the same hammer, you can happily open a 1" valve for a chamber pressure of 120 psi, the force keeping the valve shut are exactly the same.

The above assumes a conventional valve, using Brian's system the potential is much higher.

If you wanted large bore hammer valves, it would have to be a ballanced valve. I've been pondering this idea lately also.

I believe it was MRR who made an enlarged version of my " 35 bar" pushbutton valve.
His was 1/2" porting and could be opened by hand at 40 bar IIRC.

The principle behind the pushbutton valve is exactly the same as the counterbalanced hammervalve, just configured differently.

It's also very similar to a QDV.
The QDV uses two O-rings, the CBHV used one O-ring and a flat washer wich means less wear and no trouble passing an airpassage in the pistons housing.

QDV's have been made in ( at least) 2".
No reason for the CBHV not to function at the same size.
The only thing I can imagine is that the travel could be a problem.
A 2" CBHV would need to be knocked in quite some distance to get full flow.
A rotating hammer, like I like to use, would have to be ridiculously large.
It would probably be better to use a linear hammer.


Yep...the CBHV:
Pistonvalve -like performance, but without the waste of pilot volume and multishot without much effort in a compact design.

If you have a lathe it's not that hard to build it into a seamless pipe and have a section of pipe sticking out to house the linear hammer mechanism..
A plug connected to a (regged) HPA or CO2 paintball bottle on the opposite end...Hmmm

I'd go for the 1" caliber version...The valve could be housed in a 1.5" pipe..
That would make quite an interesting PCP...

What would they say at your local airgun shooting club..

Brian the brain wrote:I believe it was MRR who made an enlarged version of my " 35 bar" pushbutton valve.
His was 1/2" porting and could be opened by hand at 40 bar IIRC.

it was far_cry
http://www.spudfiles.com/forums/posting ... 34167.html

Nice link

Brian the brain wrote:If you have a lathe it's not that hard to build it into a seamless pipe and have a section of pipe sticking out to house the linear hammer mechanism..
A plug connected to a (regged) HPA or CO2 paintball bottle on the opposite end...Hmmm

I'd go for the 1" caliber version...The valve could be housed in a 1.5" pipe..
That would make quite an interesting PCP...

What would they say at your local airgun shooting club..

Subtle hint noted hammer valve-in-a-pipe is basically what this mechanism is in aid of, albeit with a "conventional" hammer valve.

Gun Freak wrote:Nice link

lol
http://www.spudfiles.com/forums/updatec ... 18705.html

I have saw that video long long ago, the "Mrairshot"(video owner) wasn´t very nice to me didn´t knew he was far_cry
but the valve looks interesting, any diagram?