Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
ONEWING wrote:I dont know what KLM is so I'm assuming its "pipe".
Suprisingly after sitting outside under a walnut tree for many years the old girl fired up just fine today, after a few bursts of dirty water and dead spiders its good to go.
im no expert here (trust me i have never EVER worked with copper before) but i think k, L and M are different types grades of copper, each with different properties (the most important is ability to withstand pressure )
ONEWING wrote:in fact it would have been posted on the old old spudtech forum 9 years ago.
I think I have a diagram of it archived somewhere, I'll look it up when I get home
True there was one I drew in paint both side and top view, and also an animated gif explaining the operation of the piston valve. The gif got spread about a lot but it be common knowledge now. Couple other pics that were posted and lost were a side view and another on the rover, quality was pretty crap though as cheap camera quality wasn't as good back then!
Anyways seeing as how it actually still works I'll see what some brasso can do. Serious rust in the blowgun seems to be the only real issue.
I tried to get a movie today but this is the result, camera is very old with a tape thats been recorded over many times so quality is amiss. I could only find 1 empty shell so I thought if I started at 20psi I could get more then one shot, but alas I lost it. It was just an empty case no modifications at 20psi. Sound didn't come out so well you may have to turn your speakers up.
ps. How do you embed youtube vids? copying and pasting the code doesn't work.
Ahhh thanks Jack they are the ones. I don't remember drawing that first one but I no doubt did, didn't think I put an O-ring in the piston maybe I drew that as an ideal picture rather then what I did but then how did I know 2" Cu fit into the bush reducer... I'll have to screw it open to find out whats inside there. But then the looser tolerances may be the reason it still works full of mud and spiderwebs.
I have some primed cases here so I shot one around until it went off, average fps is in the 290's @ 20psi with an unmodded case and just over 600fps @ 100psi.
Knocking the primer out and replacing it with a nail gave around 400fps at 100psi, chrony result is below.
Thats my niece below, she attempts to pump it up then runs around and cries when she cant pull the trigger.
Attachments
Started something!
Shotshell + nail at 100psi
Last edited by ONEWING on Sat Apr 17, 2010 5:31 am, edited 1 time in total.
ONEWING wrote:Thats my niece below, she attempts to pump it up then runs around and crys when she cant pull the trigger.
girls eh
Fantastic results, it's really good to see that one of the launchers which inspired me in my youth (I had saved the diagrams in 2003!) is still up for it
hectmarr wrote:You have to make many weapons, because this field is long and short life