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Vex robotic cannon

Posted: Wed Dec 22, 2010 10:58 am
by metalmeltr

mechanical workings


firing
too bad it's just one shot

Posted: Wed Dec 22, 2010 11:07 am
by Hotwired
Automated refilling but no mag also you can rotate the turret and elevate the barrel but you can't aim in any meaningful sense.

I'm sure we've all imagined making something along those lines :)

Posted: Wed Dec 22, 2010 12:40 pm
by ramses
Hotwired wrote:I'm sure we've all imagined making something along those lines :)
Yes, we have

Posted: Wed Dec 22, 2010 1:14 pm
by Technician1002
The VEX launcher is very inefficient with the air supply as there is a small diameter hose to feed the air into the barrel. Adding a chamber to the moving barrel with a larger orifice and short path would vastly improve output power with no change in input air consumption, or it would consume much less air per shot for the same launch velocity.

It is a cute robot, but not an efficient launcher design.

Posted: Wed Dec 22, 2010 2:58 pm
by metalmeltr
I was drooling over the robotic mechanics, I agree that it is not an efficient launcher.

Posted: Wed Dec 22, 2010 8:03 pm
by Moonbogg
Nice. The builder doesn't seem as paranoid about his welded aluminum as I am about mine :lol:

Posted: Thu Dec 23, 2010 12:39 am
by metalmeltr
TIG weld will hold no problem
any good weld should be stronger than the substrate
in addition he is working with much lower pressures if your talking about your hybrid.

I have added some pictures of weld failure and a glue used in automotive assembly that was part of my recent school science project.
Pictures coming soon
begining to dislike SF uploader

Posted: Thu Dec 23, 2010 8:37 am
by jackssmirkingrevenge
Shame about the poorly designed cannon, it could be made into a much more efficient and powerful multishot with relative ease.

Posted: Thu Dec 23, 2010 9:41 am
by Technician1002
The issue as shown above in the photos is either the weld is weakened or the metal adjacent to the weld is weakened. Note the bead weld broke at the weld, not somewhere else. The failure at the welds is common. This is why high pressure tanks are never welded. Only low pressure tanks such as Propane tanks are welded.

Oxygen, Argon, and CO2 and SCUBA tanks are one piece construction. They do not have welded fittings.

Posted: Thu Dec 23, 2010 9:45 am
by metalmeltr
The bead weld failed in the HAZ of the weld, the weld itself did not fail, there is a small amount of the base material from the failed piece still in the right side of the weld bead.