Canadian Airgun Forum

that would be the best alternative Michel great idea and it had crossed my mind before because, even though the brass look awesome along with the aluminum ones...
the problem I had with an aluminum one was it stared to rub scrap on the back end of the piston into the tube and it left some pretty nice gouges on the tube... , I had to finally remove it and went with the stuffed piston mod, no more scraping and was much smoother in pumping. A Delrin back section would be ideal in my opinion...

"or" put two O-rings one on the front as they are now obviously and one in the back half just a bit ahead of were it splits and the pump arm attaches, that way there in no more play in between the piston back half and the tube, and the piston will stay true throughout the pump cycle....just a thought....

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"A candle loses nothing by lighting another candle"

Only problem with that Ace is eventually the cocking arm slot cuts the oring even after deburring, been there. Best IMHO would be a 2 part, brass and Delrin sleeve outer to take up the pumping friction.

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May the cry of the pack be with you upon your hunt

Whitewolf

Choice is a wonderful thing, and "$15 shipped" is an utterly amazing price. Must be one heck of a fixture.

Al

yes your right Kim didn't think about that....
well like I also said the two part Delrin back half and brass or aluminum front section would be ideal....


no doubt that's an awesome deal Al same with Michael's don't think you'll find better....

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"A candle loses nothing by lighting another candle"

To provide the materials, machine tools/tooling, a place to use them in, labor, time answering emails/pm's/questions, packaging, standing in line at the post office and actually include the shipping charges....no...not going to find a better deal than $15...that's FREE IMO.

I'm simply not THAT generous.

Al

This is a new one on me. (no malice intended here) Just something I haven't seen yet, and at last count there's 17 pumpers here, dating from the late 50's to almost present day. Almost all are on some sort of flat top piston system, and I have yet to see the cocking arm slots cut an o-ring.

What does cut O-rings occurs on the initial installation- the pivot pin holes can be really bad for this, and in extreme cases, be difficult to completely polish out.

I've tried with the secondary o-ring on the rear piston half, and for me, all it seems to do is increase pumping force...

I have used the delrin rear behind an aluminum head, and it works well....

Regards,

Doc Sharptail

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"Ain't no half-way"
-S.R.V.

I simply start the manual lathe that I converted to CNC to cut the pistons and the pivot ends. They are the same, except the pistons have the o-ring gland.
Then I put the pivot ends into my fixture for my manual mill, again converted to CNC to cut the slots and drill the pivot point.
I make one by one in the lathe, but in the mill, it's 50 at a time. Just putting material in, either way...

I converted to CNC and use Delrin to keep the prices down, on the advice of ustilago years ago... He and Vagrant supplied me with endless advice and asked me to just continue in the spirit of the airgunning community and help out. I don't mind running my machines from time to time to make inexpensive parts. I do have more expensive parts, aluminum, brass and titanium...

Michael

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Daisy Red Ryder

What could an air-gunner need in titanium? Interesting!

Regards,

Doc Sharptail

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"Ain't no half-way"
-S.R.V.

Absolute overkill, but really shiny...

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Daisy Red Ryder

$15 shipped, that's charity work there!
I don't even know if I can ship a CD to my next-door neighbour for that price!

Thanks to all you fabricators, Al, Michael, others - it's great to have you people with the skill set and means to make these items for our hobby!