false piston: how the hell do I make that?

Hello Instructonauts, I have a bit of a problem. I need to make an object with a piston like action. This wouldn't be such a big deal if I could actually just use a piston but I can't. I need a method for creating a piston movement of a cylinder inside a tube so the device moving the piston cannot be any wider than the piston. I considered pneumatics but that would require supplies I do not have and have never worked with. Does anyone know a way to make this object?

sort by: active | newest | oldest
1-10 of 14Next »
gr33ko8 years ago
or maybe attach the piston to a worm gear. as long as the piston isnt compressing anything or moving fluid you should be ok
gr33ko8 years ago
Have you done any research on linear actuators? This may be your solution!
lemonie8 years ago
Marcos8 years ago
Are you looking for a project idea, or do you need to build a piston like an internal combustion engine? If it's the first one, why not make a fire piston, and get a cool gadget in the process. If you don't know what they are, look 'em up. I think there is at least one instructable on how to do it. Warnining Will Robinson: it's not easy, but it will be satisfying when you succeed. Let us know what you do.
wow-amazing8 years ago
Maybe a mouse? Or a finger!
Goodhart8 years ago
Would the drive similar to what a locomotive uses to transfer energy from piston to wheels, work? In reverse of course...
finfan7 (author)  Goodhart8 years ago
isn't that just another classic piston?
Yes, but I thought you were concentrating on the "drive" which can be "outside the wheel" like the locomotive, or two lengths of metal slats that rotate around the outside of a pin....there are several ways to drive the piston, but I am not sure they fulfill your parameters.
chiok8 years ago
Does it need to reciprocate or is a linear motion sufficent? Or operate automatically? A rack attached to ID of the inner tube and a pinion and motor that runs along it (forward and back motion of the motor for in and out). Or a pulley system that pulls the slide like a sash window. Does that make sense?
finfan7 (author)  chiok8 years ago
It took me a moment to figure out what you're saying but once I did i realised a pully system might work. I have no knowledge of sash windows but if I use a modded servo for the drive I could probably set up a pully system and hide the wires/ropes inside "supports." Thanks for the aid, Chiok.
1-10 of 14Next »