Project batman, mini build log

[killerbanjo]

Quite a while ago somebody here did a really nifty "coaxial burst disk" launcher that used a hallow projectile to "extend" their barrel length.

This

[kydavies]

Exactly I've always loved that concept I think I'm going to use the idea of a hallow projectile and make my own quick connect (similar to jsr's ballistic knife)

[jackssmirkingrevenge]

Hollowed be thy name

[kydavies]

Just started work on the grapple launcher mk III and damn it looks sexy!!!! It's kind of a cross between jsr's ballistic knife and hotwired's copperhead launcher.
As soon as I can figure how to post pictures in a thread.

[jackssmirkingrevenge]

Something likethis?

[kydavies]

first: that video was terrifying....

No Jsr, It is not like the diagram you posted. My design is closer to that of Hotwired's copperhead pocket launcher in the way it operates (with respect to the hollow projectile, not the burst disk)
I'm just going to do a drawing to get us all on the same page but in the mean time, heres a pic of the outside (all Al)

edit: the hook/projectile is just a mock up and the big roundish thing is the trigger guard

[jackssmirkingrevenge]

More like this then

http://www.spudfiles.com/forums/mini-ca ... 20262.html



Looks good, just remember your trigger needs to be very strong - at just 100 psi for a 0.75" dia tube, there's around 45 lbs of force trying to rip it off.

[kydavies]

Im using 1/2 Al for the chamber and The trigger and latch mech are going to be made of mild steel sobi should br alright. Even so im going to beef up the trigger.
On another note, I might change to a captive piston so I can store the line inside the launcher (around the grappling hooks shaft) but the trigger mech will still be the same.

[pneumaticcannons]

On another note, I might change to a captive piston so I can store the line inside the launcher

Have fun trying to get the string to actually exit the launcher. Just keep it on the outside, multiple red flags poped into my head when you mentioned that idea. Why not use 2 trigger latches in order to spread the force more evenly?

[kydavies]

I slept on it and figured that the latch is going to be a huge pain in the ass due to the undistributed force. We'll see where I get.

[Goats spudz]

I slept on it and figured that the latch is going to be a huge pain in the ass due to the undistributed force. We'll see where I get.

Couldn't you use three latches distibuted evenly and a collet system where you twist it to fire.

[jackssmirkingrevenge]

I slept on it and figured that the latch is going to be a huge pain in the ass due to the undistributed force. We'll see where I get.

That's why using a quick connect is such a good idea, it's a ready made latch with evenly distributed force.

Something I had drawn up a while ago:

[kydavies]

Then I might as well use a quick connect fitting and a captive piston.
Damn it jsr! Beat me by less than a minute
It seems like the quick connect and captive piston is the way to go.

[kydavies]

Sorry, double post...

[Crna Legija]

Then I might as well use a quick connect fitting and a captive piston.

i did it for my ballistix knife at 250 psi near impossible to open.