Help With Making A Hammer?

[Major Collins]

ok the piece of tubing that will house the hammer is 17mm , and it is hitting the stem from a blow gun , its not the blow gun itself i made a new housing for it

im not sure what pressure i will run it at yet but nothing over 1000 psi

[Gippeto]

Just to be perfectly clear....

1000psi is nothing to trifle with...you're flirting with serious injury or possible death if you don't KNOW what you're doing.

How did you make this "housing"?

[Major Collins]

yeah i know that high pressures are dangerous , i learnt at 80 psi with thin pvc ... after that i double checked everything ....

ok first pic is the whole setup , the right end has a olive over a olive lol with hammer valve stem showing - really compact


Picture of the close up valve stem and housing , it was a 1/4 hose barb cut short , holes drilled then pushed into an olive and soldered in place

[Crna Legija]

mmm that looks pretty ghetto, i sure wouldn't use it at 1k psi. maybe 400-500, if you are sure you can solder good. anyway pressure test before you get near.

[Major Collins]

yeah i only plan to go 400ish psi when im able to get a compressor

[Major Collins]

welll yesterday i made a hammer and housing and put it together , i didn't make the trigger group yet in case the hammer didn't work and it doesnt

when i let the spring loaded hammer go it bounces back and fourth repeatedly much like dropping a basketball on the ground and watching it bounce back until it runs out of power and doesn't bounce any more.

what's the flaw in the hammer?

[Gun Freak]

Sounds like your hammer isn't strong enough to open the valve; maybe a stronger spring will help. Try toning down the pressure and it might open.

[Gippeto]

when i let the spring loaded hammer go it bounces back and fourth repeatedly much like dropping a basketball on the ground and watching it bounce back until it runs out of power and doesn't bounce any more.

Is it releasing air...or not....important information.

"Something" is returning energy to the striker if it's bouncing. If it's not opening the valve, it should be stopping pretty much "dead".

The "ideal" hammer valve opens once, and does not re-energize the striker sufficiently to open the valve a second time....easy in theory...difficult in practice. This is why some resort to so called "hammer de-bounce devices or HDD's (Steve Woodward)", "mole in the hole" (John Bowkett) strikers, "slingshot hammers"(Daystate), etc.

But no matter which way you slice it, the valve stem returning to it's closed position WILL impart energy to the striker in such a manner as to cause it to "bounce".

So...is it releasing air...or not?

[Major Collins]

yes it was releasing air , and in the mean time i made 2 more hammers
and all of them released air.

so 3 in total .The first being made with silver solder was probably the heaviest and bounced a lot - I cut it shorter but that still didn't help .The second one was an epoxied bolt bounced still but not as much as the first one , just 3 or 4 times. Then the last I used a bolt through a quick connect fitting.

The quick connect was by far the best , it hit the stem released air , but not enough to fire the spring loaded piston and didn't bounce at all .

... go on and tell me about the air releasing ,
but just quickly if i pursue with the Quick connect hammer.... would it be better make the quick connect hammer use a more powerful spring or more add more weight to the quick connect hammer

or .... should I modify the valve more so its really sensitive and so in return will require less strength from the hammer to actuate it

[Gippeto]

The quick connect was by far the best , it hit the stem released air , but not enough to fire the spring loaded piston and didn't bounce at all .

Are you using this hammer valve to pilot a piston valve?

If so, you want the valve to remain open...if the valve spring can close the valve against the force from the striker spring....decrease the strength of the valve spring.

This will allow the piston valve to pilot properly.

If you're trying for a multi shot pcp type unit...you need to try it for performance (power vs shot count vs fill pressure) before adjusting further. A string of shots across a chrony, with initial and final pressures would be ideal.

[Major Collins]

Are you using this hammer valve to pilot a piston valve?

yess i amm
, so you think i should alter the spring pressing on the hammer valve stem instead of the hammer itself?

[Gippeto]

Yes.

Using a lighter valve spring to accomplish the will reduce overall stress.

Increasing the force from the hammer spring will also accomplish the goal...but that increases stress.

If you increase the hammer spring force, the trigger "bits" will have to be that much stronger as well.

Lower stress on parts is a good thing.

[Major Collins]

hrmmmm I understand what you getting at now ...
well I went searching around the house and I got a new spring and installed it. now the stem is incredibly easy to push and it still resets .

the hammer I was using still doesn't actuate it but lets out more air that it did before so im getting closer slowly... and still doesn't bounce
.. where do i go from here ? super powered spring or more hammer weight? - my hammer now weighs about 30 grams

[Gippeto]

With your setup, you're not concerned with "traditional" hammer bounce as you would be in a pcp setup...you WANT the valve to stay open and vent the pilot volume.

Is there any tension left in the hammer spring when the hammer is resting agianst the valve stem?

If no...increase hammer spring preload...shim the spring or use a longer spring. Get it so that at rest...the striker will hold the valve open.

[Major Collins]

Is there any tension left in the hammer spring when the hammer is resting against the valve stem?

If no...increase hammer spring preload...shim the spring or use a longer spring. Get it so that at rest...the striker will hold the valve open.

what exactly do you mean tension, like the spring still wants to move forward after the hammer is resting at the valve stem

and why do I want the hammer at rest to hold the valve open ?
wont that mean when I release the hammer when it hit the stem it will hold the valve open and the stem wont be able to reset - in return just dump all the air ?