Well I've been trying to seal up an old walking stick air cane I've had . I finally found my lathe ( garage is a mess ) and spun down a little piece of delrin I bought . I'm hoping to make a few slow leakers I have hold air so I'm excited to get this one close . Now I've never had to MAKE my own parts before but I'll be keeping my fingers crossed. This is only test number 1!


Wish me luck

Thanks
Kurt

Is that strike surface part of the shaft and flat shelf the horn seal sets in? And is that seal the original design? Cause it would be hard to seal around that pin and behind the horn. The horn might seal and the shaft leak.

If so, I might be able to help .... but I’m working on this Balisong for a guy ....

Be back

Gary

Yes Gary
It's the strike surface with a tiny round nut holding it on . The seat is in perfect con cave shape . Do you think delrin is hard enough to strike on ? Maybe some glue to seal and keep air tight if not . Hmmm

Thanks
Kurt

Hi Kirt,

Ok. Working with what you have without altering the original .... and if there is a nut on the pressure side ... turn a small O ring seat on the pressure side, well clear of the sealing edges of the valve head. Put an O ring around the shaft there in the Delrin groove, and put a washer under the nut. Turn room for both O ring and shim stock washer so that the nut is in its original position. Make sure the O ring is loose in its groove and not smashed by the washer. Shin stock washer now. Maybe 12 thousandth or so. It’s only there to retain the O ring when the air blast exits the reservoir or when there is no pressure in the reservoir. The O ring will find its seal under pressure.

I feel obligation to remind you that those reservoirs are wrapped sheet metal with a brazed seam. Don’t put much pressure on them. I’ve kinda gotten used to you now. Haha.

;?)

Gary

I know that with my early trials attempting to seal threads and valves ... no manner of sealer or loctite, would do the job. I don’t know how they sealed that joint. That’s a cow or sheep horn valve head material. Don’t know if pressure squeezed it tight around the shaft. Did they use any packing tarred String etc under that nut?

That is pretty work on those old parts, isn’t it? And they are nice and bright too. Very nice work.

Gary
Thanks a bunch that's a great idea . I was thinking of threading the delrin and using a glue of some kind for sealant and getting rid of the nut completely but the the striker would be hitting the delrin. I've only been using a regular air compressor (150 psi ) to charge so no real worries there . As you know the air tank side of the cane is the easy side of the whole deal but as you said Verrrry nice work for the 1800's . The other end is a true work of art . Generally made by lock smith/ gun smith . I shattered the original horn seal during tear down as to save the metal parts . There did appear to be a lot of rust underneath so I couldn't see any other sealing parts . I think they just used a grease or oil and kept lubricants handy and the porous nature of the horn probably leaked slowly anyways .

The OD of the nut ( if you can call it that ) is .20 . It protrudes thru the end of the valve and at the mercy of the striker every time its fired .

Thanks
Kurt

Let me dig something after I have something to eat.

I think you can use a much largervalve head. That looks very small for that seat. I wouldn’t be surprised if someone hot rodded it.

And .... this kind of valve is very hard to seal under about 400-500 psi. So;sealing at 150 would be darned good

Can’t find it yet

That valve head looks to only be about ... .375”? Seems the ones I’ve seen were round ball like and the seal was more like .500” or even more. I have measurement somewhere.

I see two seal ring ghost tracings on that cup. What is the outer shiny ring’s diameter?

Gary

I’ll look other places as I wirk

Kurt,

Those are some interesting pieces. I have never seen an air cane in real, especially from 1800's. Delrin is a good choice for the valve (IMO). Gary is assisting so you are in good hands


Show a picture once its completed and firing, would be neat to see.

Pedro

Howdy Pedro
Well I'm not a builder like you and Gary but I do like to tinker. I figured if they built it in the late 1800's how hard can it be to fix . Hehe

Thanks
Kurt

The outer diameter of the seal and the larger piece by the threads are both .375 . The seal pushes against the back piece and the little nut (separate in pic) holds it in place . The step in the seal is only a relief cut to allow it thru the housing . The .375 part is the area that does the sealing . I looked on the face of the seat again and and it does appear to be able to accept a seal around .750 and would set in ANOTHER concave area in the valve that I didn't really notice before .

Thanks
Kurt

Thks Kurt,

K ... here is a theory. I think some previous owner was crazy enough to runsome HP Air in that reservoir. Now;the original cane would have been hand pumped. Probably not seeing over 500 psi. With 500 psi acti g on the back of a larger valve head, the cane firing mechanism was strong enough to open the valve. But, you put 3,000 psi in there, and if you don’t blow yourself up ..., that 3k acting on the larger valve head won’t allow that mechanism to open it. So; they needed a much smaller area of valve head for the HP Air to act against. Maybe a 1/4 of the original area of valve head and the mechanism could fire off the HP Air. So they butchered the valve head. Took it down to .375”. (Not a bad guess if I do say so haha).

That dish valve seat would allow all manner of valve head sizes to find a seat. I’d hydraulic test the reservoir to about 1,500 psi then run CO2. IIRC .,,, in the warm sun that CAN get to as much as 1,100 psi. Normal temps would run about 700 psi I think. This is old knowledge. Verify. Now, if you were gonna rum air, I’d test it to 1,000psi and run it at 500psi. Or, if you could ... rig a Barnes Relief Valve or a blast disc for safety.

If you say Valve head of .750” would fit, I’d say try making one of .600 - .625”. Use the O ring suggestion I made. Then run that at about 500 psi-ish, and I’d bet you’d enjoy it. Gotta test the reservoir though. Oil won’t blow up. Air will.

Heck ... all this is making me wanna play too.

Gary

Ok send me the Bill !
After all that work ... I don't think it was leaking all that bad . Haha I could get off a couple of shots before it emptied. I completely understand where and why what you said though . I like the hydro testing idea . I never knew or even thought about it .
Experience has spoken !

Thanks
Kurt