SpudFiles

I've wanted to make a hammer valve for quite a while now, recently while contemplating a micro cloud BBMG I figured I'd try and combine the two ideas based on a schrader valve as a pre-made hammer valve.

The prototype is still under construction but is basically this concept, nothing original but I hope it will work well.

Here's what I've made so far, all that's left is a bit of reinforcement to the attachments on either end of the hammer tube and I'll hook it up to my compressor for some testing. Note how servicable and tweakable the construction is, essential for the sort of fine tuning that such a design will require.

Once I get the valve to fire reliably, I'll think about hooking it up to a barrel and reloading system.

edit: valve in action initial test videos

jackssmirkingrevenge wrote:Note how servicable and tweakable the construction is, essential for the sort of fine tuning that such a design will require.

I'd make a comment on this, but I'd no doubt receive a response that called into question how I make use of my private time.

On a more sensible note... looking good so far, interested to see the results.

Ragnarok wrote:I'd make a comment on this, but I'd no doubt receive a response that called into question how I make use of my private time.

You'll always be a wanker but I meant it's servicable and tweakable in contrast to my usual epoxy sarcophagus style of construction

Wow just wow I hate you now. Jk actually I suggested long ago about using a shrader as a hammer valve. Some of people told me that it would have such little flow that it wouldn't be worth while (I think it was hub but I can't remember) but scinse you will be using this on a micro bbmg with high pressure I don't see a problem.

What about using it as a pilot valve for a fast-resetting piston valve? This could be a good way to create pulsed-flow.

Nice.
Though I think that that hammer is asking for an o-ring. Also it may need to gain some extra weight. This weight could also be attached on the other end of the stick, making it tweakable without even opening up the gun.

The shrader WILL need a good amount of force to open. Increasing the pressure to make the hammer gain enough momentum will also make it harder to open. Gotta find a balance in that.
I fear that this mechanism will barely have enough power to run itself (needing all the pressure to cycle)
Maybe you need to crank up the ratio of " air/pressure output per hammer":"air/pressure needed to cycle"
This could be achieved by using the shrader to pilot something, allowing for a much greater amount of air to be pumped into the system with a relatively small hammer. This would however urge the need of the hammer to strike the shrader on the outside of the gun.

I should stop rambling and wait for the results of the shiny thing.
Is it me or are "prototype threads" always hijacked by discussion of how to improve the prototype?

jackssmirkingrevenge wrote:but I meant it's servicable and tweakable in contrast to my usual epoxy sarcophagus style of construction

So did I! :tongue3:

As you've no doubt noticed, it's a common complaint against using your epoxy construction methods. The inability to adjust after construction.

Still, I suppose it's cheap enough you can get away with it.

wow. congrats on actually making it. i'm one of those guys that sticky_tape mentioned that thinks that a schrader has too little flow. but mostly i think that it has too much resistance to opening and the hammer spring needed to open it will be too stiff to recock. that is why i want to use the hammer valve that Ant posted (screw head and o ring). it opens easily and has plenty flow.

if u can make it cycle u will be king and i will loyally serve.

This could be achieved by using the shrader to pilot something, allowing for a much greater amount of air to be pumped into the system with a relatively small hammer

There's just no getting away from me is there?

Jack, I'd love to see this thing work.
I'm a bit confused I think.
Why is the hammer housing so incredibly long?

Brian the brain wrote:Why is the hammer housing so incredibly long?

I think it's for the hammer to gain enough speed to punch open that schrader valve.

Anyway jack, nice prototype, now go and build a "gun" around that valve!

i think that the length allows the hammer to gain speed also alowing him to use a very low resistance spring. but for it to work u gotta have enough flow to fill it. i don't think a schrader can provide it. correct me if i'm stupid .

SEAKING9006 wrote:What about using it as a pilot valve for a fast-resetting piston valve? This could be a good way to create pulsed-flow.

Interesting idea but a pop-off pilot is probably a better way to go about it.

I think that that hammer is asking for an o-ring. Also it may need to gain some extra weight. This weight could also be attached on the other end of the stick, making it tweakable without even opening up the gun.

O-ring = friction so I don't have any planned for now, just a very tight fit aluminium bolt. As to weight variation, I can easily add it to the existing bolt or make a new one if necessary.

The long tube is there to allow for more springs to be added if greater compression is needed.

It's true that a standard schrader has quite a bit of spring tension on it, but with a bit of abuse the stem can be persuaded to open a lot easier. It will still have limited flow, but remember this is for a 3mm calibre launcher, I'm not using it to launch tennis balls.

Is it me or are "prototype threads" always hijacked by discussion of how to improve the prototype?

Isn't that the point? I'd rather get constructive criticism than a spate of tH15 r0XX0rZ!!!!11!!1! comments

As to this particular prototype, most concerns expressed so far are valid but I think that the provision to alter spring strength and travel as well as hammer weight should allow me to (eventually ) find the right balance and make it work.

Tests at 110 psi planned in half a day or so, as always watch this space fo results, good or bad.

jackssmirkingrevenge wrote:I'd rather get constructive criticism than a spate of tH15 r0XX0rZ!!!!11!!1! comments

tH15 5uXX0rZ!!!!1111 eleventyone!!!!11

I kid!
Mostly...

Actually, I'd better start being nice, else you'll take advantage of the opportunity to get your own back with what I'll be presenting in a few weeks. Because that's when you'll get to be evil about the flaws in one of my creations.

EDIT: Grammar error.

Ragnarok wrote:else you'll take advantage of the opportunity to get your own back I'll be presenting in a few weeks.

I'll probably be too amazed to see something new actually emerge from your workbench to do so

In the meantime, played around with a schrader and managed to increase the stem travel while adding a much weaker spring, should do the trick.

jackssmirkingrevenge wrote:I'll probably be too amazed to see something new actually emerge from your workbench to do so

Blast! He's already started a counter assault!

But yeah, it has been a long time. It's not that far off 2 years since I did a large project - not just tweaks or "thrown together" pieces.

We'll see if my workbench lives up to expectations.