# super simple pneumatic drop down prop



## 1031fan

not gonna do a whole lot of explaining unless someone wants me to - its really straightforward and simple - took a few tries to get the linkage right - i was tryin somethin more complex, but when i broke down all the elements, this is what was at the core - and it works great - mount it in a hallway or room above the ceiling, manually trigger the rainbird sprinkler, and whatever you want that is LIGHTWEIGHT will fly down from the rafters - cost - maybe 30 bucks - most expensive parts bein the solenoid and the door closer

this was somewhat frustrating after building my bed thrasher using the commercial pneumatics because with hack jobs we are really limited, but for 30 bucks - its hard to beat


























feel free to ask any questions if you want to know more - riley


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## Front Yard Fright

Could you post a video of it in action?
I believe I know how it works but I am not sure.

Could it be switched around?
Meaning could it bring something up rather than pushing something down?
.


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## 1031fan

sure - i can post a quick clip here when i get a chance

your right, the whole rig could be flipped upside down, but then it wouldnt sit flat - if i wanted it to flip something up id probably mount the cylinder a bit differently, but then again, if i wanted a prop to go up id probably just use a 4 bar linkage

only trouble with this one is - - the weight of the prop at the end of the pvc pipe can NOT be heavier than the return spring in the cylinder can pull back up - however, this does not mean that the prop can be the 30 lbs or whatever the spring weight is because of good old physics and torque - sooo - the prop that i put on will have to be super lightweight so the spring call pull it back - this problem would easily be eliminated with commercial parts and a 2 port cylinder - with this the prop wouldnt be relying on the return spring to hold it up, but rather the air pressure coming in for the port - but alas, this will have to do in the name of saving some cash


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## skeletonowl

$30? Good Animation? And I can build it? You sold me! I'll have to seriously look into this!


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## Brckee1

Nice simple design. simple is always better than complicated for reliability. You could always add an external spring or counter weight to help balance the weight of a heavier prop.


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## 1031fan

thanks jim! i agree with the simple = reliable - good old KISS method - and yeah - good call with the external spring - i tried a bungee cord that you can see in the first pic - but in the last pic you can see what happened to it - SNAP - so i think im gonna go with either a spring next or possibly the counterweight right below the mount for the cylinder - the counterweight might actually be the way to go now that you mention it - in any case - this is just a side project to keep me my sanity from all the walls that im neck deep in - - - - more to come - riley


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## oct31man

Hey 1031, any progress? I'm looking forward to seeing how this turns out. I like the idea!


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## 1031fan

thanks oct man - actually this one has been put on hold for a while - i figured it would be of no use if i didn't have any walls to put it in - haha - so ive benn concentrating on structure mostly latley - but it will get done - dont worry - i think it will be a decent scare as well - thanks for the interest - stay tuned - riley


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## dionicia

I cant wait to see the how-to on this one.


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## Eric Striffler

I can't wait to see it in action!


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## Northern Touch

hey 1031 U ever get this one figured out would love to see what U came up wit...


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