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Posted: Tue Feb 02, 2010 11:56 am
by starman
Very solid golfin' baller. Looks heavyish...thankfully a shoulder mounter.

What did you use to sleeve over the 2" sched 80 at the breech? Also, looks like you abandoned the through-the-chamber pilot. What did you replace it with?

Posted: Tue Feb 02, 2010 12:12 pm
by D_Hall
starman wrote:What did you use to sleeve over the 2" sched 80 at the breech?
Nothing. The sch 80 fits over the sch 10 with very little slop. Beyond that I just had the forward end of the 80 welded to the 10 to create a seal and lock everything in place. Something I did not anticipate, however, was that the weld would deform the barrel ever so slightly. You can't actually see it looking down the barrel, but right where the weld is the barrel necks down a bit. Result? It works BEAUTIFULLY to hold the ball in place before firing. I drop the ball in, push it forward maybe an inch, and it's held pretty solidly in place until firing.
Also, looks like you abandoned the through-the-chamber pilot. What did you replace it with?
No, I didn't abandon it. I embraced it. That was the mental break through that allowed me to finish the gun. As stated previously, I won't bother to build a gun that isn't clean and until I came up with the thrugh-the-chamber pilot I couldn't come up with a pilot/trigger system that met my requirements for "clean design."

Posted: Tue Feb 02, 2010 2:57 pm
by D_Hall
dewey-1 wrote:Could you post a screen shot of your GGDT parameters for this valve?
Done. Note that the valve efficiency is lower than one would normally expect due to the fineness of the reservoir. In other words, the tightest spot for flow is in the valve's inlet, not the valve itself. This was a sacrefice due to ergonomic concerns. I suspect I could get another 5-10% efficiency out of the valve if I had a larger diameter reservoir feeding the gun.

Posted: Wed Feb 03, 2010 12:55 am
by ramses
Nice cannon.
You could probably go hybrid with it. Or at least up the pressure.

Posted: Wed Feb 03, 2010 1:37 am
by jeepkahn
http://www.spudfiles.com/forums/dd1wood ... 17514.html

Ahem.... Nice Cannon D, Interesting name choice..cough...

Lol...

Posted: Wed Feb 03, 2010 2:39 am
by D_Hall
jeepkahn wrote:Ahem.... Nice Cannon D, Interesting name choice..cough...
LOL. What can I say... Great minds and all that.

Posted: Wed Feb 03, 2010 2:43 am
by Ragnarok
ramses wrote:Or at least up the pressure.
You might not have noticed, but D_Hall is not known for pushing components outside their defined specifications.
I imagine he's already at the rated pressure of the QEV, and very much doubt that the urgings of people on an internet forum will convince him to go any higher.

Posted: Wed Feb 03, 2010 4:38 am
by jeepkahn
Ragnarok wrote:
ramses wrote:Or at least up the pressure.
You might not have noticed, but D_Hall is not known for pushing components outside their defined specifications.
I imagine he's already at the rated pressure of the QEV, and very much doubt that the urgings of people on an internet forum will convince him to go any higher.
And why would anyone who's built a semi(truck)sized hybrid need to prove themselves by exceeding spec'd ratings??? If he wants MOAR, He has Vera...

Posted: Wed Apr 21, 2010 1:05 pm
by D_Hall
And I finally have video of the gun in operation....

[youtube][/youtube]

Posted: Wed Apr 21, 2010 1:38 pm
by jackssmirkingrevenge
Clucking Bell! and there I was, all happy with my little casio :roll:

Posted: Wed Apr 21, 2010 2:19 pm
by D_Hall
jackssmirkingrevenge wrote:Clucking Bell! and there I was, all happy with my little casio :roll:
Photron. Accept no substitutes. :D


(Truth be known, I wouldn't mind having one of those Casios myself. Can't beat 'em for bang for the buck.)

Posted: Tue Sep 27, 2011 2:58 pm
by mattyzip77
Hate to kick up a old thread, however Dewey and I were in discussion, and My question to to you, DHall, is how far is this cannon capable of putting a golfball? I am not familiar with ggdt yet, however I would think it would be capable of greater than 400 yards??

Posted: Tue Sep 27, 2011 3:08 pm
by dewey-1
Matty look up and see that he posted a screenshot of valve parameters in case you missed it.