Do you know hydraulic cylinders (aka hydraulic motors) ?
Well, this slideshow is about an electric "counterpart" prototype, which use a DC motor, a bolt & nut, and an aluminium cylinder.

There is no casing, and no mean to prevent the cylinder from rotating yet ... but that's just a prototype ...

PS : thanks to Gmoon and Proteus who told me how it was actually called in English. =o)
Jay-eeS5 months ago

nice one ..thanks dude

yalex11 year ago

that is great, but why not buy from our factory of linear actuator, price is only US$20+, link: http://www.ele-b2b.com/linear-actuator-c-17.html

To keep it from rotating, I epoxied another, much smaller diameter tube alongside the long tube. I then cut out a single piece of square plywood, and drilled two different-sized holes next to each other in the wood to accept the two glued-together cylinders. I lubed the assembly with a small amount of petroleum jelly. It lubes the parts, but the keeps the wood from swelling. I intend to use this as a simple "latch" to keep a door from opening when it shouldn't. Thanks to the original poster for a great idea. It got me "over the hump" on this project.
Excellent, simple idea. I have a bit of a different application that is similar that you might enjoy. See http://www.youtube.com/watch?v=GmC4WoLkvBs&feature=youtu.be
angler3 years ago
this is ingenious.
bredend3 years ago
Very cool!

If you connect the tube to the motor, you can use the bolt head as a mounting point.
jaweee4 years ago
thank you! this was so helpful, now my next problem, how to make it retract without reversing its turn?
copper tube4 years ago
i need 1
n1cod3mus4 years ago
this is brilliant and had given me the idea to build my own one, slightly larger, i will be welding to my motor shaft so that should hold it nicely.
Kiteman7 years ago
It's sort of a linear worm drive. I can see this getting used in Hallowe'en animatronics. The glueing is a weak-point, though - it might shear under a load. The motor's pulley and the head of the bolt might need keyed together somehow.
gn0stik Kiteman6 years ago
JB Weld.
lane29 gn0stik4 years ago
tried but i had a problem with it getting in the threads of the bolt
andy Kiteman7 years ago
One might try to drill a hole in the head of the bolt, dead centre or as near reckoning as required, making sure the hole is marginally smaller than the diameter of the axle. Heat the head of the bolt, slide/hammer in to position and allow cooling. Most toy/hobby motor axles that I have come across tend to poke out of the back of the motor, so it could be conceivably hammered on a flat surface without messing up the motors innards. Alternatively if one wished to make a secure fit without the aid of drills, rotary tools or such one could get a hex size adapter (like the ones with a square shape one end and a hex on the other) and epoxy the whole assembly together. Big and messy I know but it could work. Drew
eL3VEn5 years ago
How have your results been with this? I can't find small enough actuators for my projects so I'm willing to try this.
nahian015 years ago
great idea make a lot of my projects easier
sharlston5 years ago
but wont the nut just spin with the motor shaft?
Proteus7 years ago
Linear Actuators are hard to come by where I live, I tried this before with stepper motors it works surprisingly well!
ok my idea is what if we use a belt and a big wheel to attach the small one which is direct and fast when rotates. it will make the motion realistic as in the backhoe slow moving up and down.
PyroMonger6 years ago
this is a godsend. I've been thinking of ways to make my own actuator since funds are low and this is almost identical to the ideas I had. glad someone made it so I can see how I could do it and or improve it. great 'ible
Erobots7 years ago
nice idea....
Patented7 years ago
What is this??
chooseausername (author)  Patented7 years ago
It's a linear actuator. When the motor rotates, the aluminium cylinder (when you prevent it from rotating) slides along the main axis.
It looks like a fat lightsaber... haha. Nice job! +1 rating, I like how it looks. :P
Bongmaster7 years ago
kinda like the head moving actuator in a floppy drive and cd drive :) kool idea :D
zachninme7 years ago
gmoon7 years ago
An actuator...
chooseausername (author)  gmoon7 years ago
thanks ! =o)