loading
Picture of Making a Powerful Linear Actuator
I looked at buying a Linear actuator but they are too expensive for the project i wanted to do so I thought i would make one and document it for Instructables so that others can follow what i do for their project or improve on it.

I have 2 options for you guys here, the frist option I tried and a slightly improved model.
 
Remove these adsRemove these ads by Signing Up

Step 1: What you will need


You will need the following materials and tools

Tools:-

Welder - Optional

Hacksaw - a junior hacksaw is fine

flat head screw driver

vice - i used a hobby vice which was fine

Mitre block

Hammer

a metal file

--------------------------------------
Materials : -

Epoxy Resin - Araldite is what i used

threaded rod - M10

Nuts - M10

piece of clothes rail

clothes rail holder

DC Motor or a Cordless Drill with forward and reverse

Petroleum jelly

Step 2: Picking your drive method

Picture of Picking your drive method
IMG_1677.jpg
IMG_1675.jpg
You need to choose your drive method well, my original plan was to use a sewing machine motor to drive my actuator figuring i could reverse to polarity to reverse the motor. it turns out a sewing machine motor uses AC current and a AC motor will only spin one way regardless of which way round the polarity is. to get it to reverse you would have to use gears which i wasnt prepared to do.

However a DC motor will spin the opposite way when the polarity is reversed, so i broke up a cordless circular saw for the motor, it wasnt very good as a saw anyway, i cut the cashing up and kept the gears that are in it in place.

Your other option is what i have ended up choosing which is a cordless drill, the advantage of this is that it has a chuck so what ever you put in it will be centered.

Step 3: Inner rod

Picture of Inner rod
IMG_1574.jpg
IMG_1575.jpg
IMG_1577.jpg
IMG_1578.jpg

the inner rod of the actuator is basically a threaded rod

now if you are using a cordless drill as i have decided to do in the end then you could just cut it to the correct length with enough to fit in the chuck of the drill extra.

if your using a DC motor its a little more involved you need to attach the rod to the shaft of the motor.

using the drive wheel from the sewing machine motor you need to weld a nut on the end of it making sure its as central as possible.

then just thread in the rod in to the nut as tight as possible and weld that to the nut, put a spot of expoxy resin on the nut to hold it to the pully centralised let it set, then put it all on a screwdriver to hold it while you weld it.

now you could use a long bolt instead of the nut and rod but i couldnt find one long enough as i wanted at least 20cm of travel in the rod.

now that its all welded together its not going to come appart and you can used the sewing machine pully to attach it to the shaft of the motor as it had a little screw in the side of it which you can tighten on to the rod of the motor.

Step 4: Outer Casing

Picture of Outer Casing
IMG_1660.jpg
IMG_1662.jpg
IMG_1663.jpg
IMG_1665.jpg
IMG_1666.jpg

the outer casing is the same no matter which method your using, basically a nut inside the rail.

cut the rail to the same length as the threaded rod using the mitre block to keep the cut as straight as you can.

the nut was a tiny bit larger than the rail was but thats ok because it would mean it would be tight in there.

i cut the rail to length then i cut slits in the end, about 6 of them so the rail would open as i hammered the nut in to it.

hammer the nut in to the rail, make sure the nut is level before you carry on.

put the rail in the vice with the nut facing up and mix up some epoxy resin, paste this around the nut and in the slits being careful not to get any inside the nut where the thread is as this will mess the actuator up. You need to let this set for about half an hour before you can work on the other end, and leave it for at least 24 hours before you use it to make sure its gone off properly.

now you can put epoxy resin inside the rail holder and put the other end of the rail in to it, not the nut end, put it in the vice and clamp it so it pushes the rail holder tight to the rail, now put epoxy resin around the edges filling in the gaps and let this set.

Step 5: Put it together and your done

Picture of Put it together and your done
IMG_1669.jpg
IMG_1673.jpg
IMG_1667.jpg
all you have to do now is to thread the outer casing on the the inner road and your done.

i have pictures of the threaded rod on its own in the casing which then can be put in to the chuck of the drill and used that way, but also of the one that can be used with the DC motor.

Some of you are saying to your selves "where does the petroleum jelly come in to it then" well i use this as a cheap grease, best thing i have found is to mount the rod on your motor or in the drill and get some petroleum jelly on your fingers and use the motor to spin the shaft slowly while you grease the rod, this will provide less friction on the rod when its spinning up and down on the nut and hopefully make it last longer and it wont squeak when its turning ;-)
MiguelJAS5 months ago

Great and simple project! Congrats!

Do you have any video of the actuator working?

I'm trying to build something like this, but I have to admit I'm struggling with something along the way... I feel kind of stupid because there's not a lot to it, but I'm just not getting it... :p

n1cod3mus (author)  MiguelJAS5 months ago
sorry I don't have any video and I have moved house since I made it and its been binned a long time ago.

Thanks anyway! I know it's an easy concept so I just need to revise my prototype.
I'm trying to build an actuator to push something out of a pvc pipe. ;)

Michael_oz5 months ago

A while ago I picked up two GMC (cheap) 18V drills at our local recycling center.

Two 18V motors and gearboxes and speed control triggers. Bonus chucks. And the clips fit on my 18V Roybi batteries.

I contacted my local plastic recycling (curb pickup) and they were happy for the ABS shells to go in the recycling. (minus the rubbery grips)

So don't bother buying a drill.

Quistie1 year ago
This is awesome, btw. Do you think this would work for a TV lift? I want to build a cabinet to house my 47inch TV and all it's equipment. Thank you!!
Muyi Quistie1 year ago

What your TV lift output? Now we have a IR remote system for TV lifts open/close that control by your TV remote, but no need extra remotes.

n1cod3mus (author)  Quistie1 year ago
yes I think it would work, but I think it would be slow
Ok perfect. Thank you! This is going to be great- now to convince my dad to help me build it!
farazjz1 year ago

i just advise that DO NOT GET IT NEAR FIRE because epoxy can not sustain fire heat

Costarus made it!1 year ago

A good thing! I do linear actuators. Use motors 30-60 rpm and motors of drills with gear. Apply actuators for automatic airing of hotbeds and greenhouses. Much better hydraulics.

Screenshot_30.jpg
Thanks for the instructable! Say, what's the estimated cost of the total unit? It would also help if you posted the make/model/part no. for any components if possible.
n1cod3mus (author)  carnotricecooker2 years ago
I estimate about £15 not including the motor which was salvaged.

It hard to give makes and models as it was just an old circular saw which I had kicking around originally from B&Q but they dont make it any more.
n1cod3mus (author)  n1cod3mus2 years ago
to be honest most of this was just junk I had laying around at the time. I have since decided that this actuator Is not going to do what I need it to do and I'm going to build a scissor lift arrangement.
trey7102 years ago
Just curious. What would something like this lift. I'm wanting to lift about 30 lbs and i'm not sure if something like a drill will do that.
n1cod3mus (author)  trey7102 years ago
you might want to put it though a gear box first to get the torque, you could use a wheel chair motor, or washing machine motor.
n1cod3mus (author)  n1cod3mus2 years ago
you would also need a bigger thread and nut, as you dont want the thread to be stripped off. my one lifted about 5kg with out issues.
Thanks for the feedback. After I saw this I was digging around a bit more and found a scissor lift idea I liked.
In the end I'm trying to build a standing desk kind of like the Wallaby standing desk. I think I can take an old car jack, weld a pole to it vertically and place platforms on the pole. A simple drill attachment to the scissor jack would raise and lower my desk.
Another weekend project....
n1cod3mus (author)  trey7102 years ago
excellent, do you have the link to the scissor lift project as I too am building something which would be quicker and more stable with a scissor lift.
n1cod3mus (author)  n1cod3mus2 years ago
another idea might be to make a scissor lift.
I was wondering if there's a way to actuate this linear actuator by way of infrared remote control like in this link: http://www.youtube.com/watch?v=XLodZGNvV9k
boston75132 years ago
Wicked cool instructable I would not have thought it was so easy. I was thinking about how linear motors work before I did this search and I hadn't thought to do it this way Thank you!
n1cod3mus (author)  boston75132 years ago
no problem
heathbar643 years ago
You will find some very useful gears in an old kitchen mixer. they have a worm gear and two ring gears to go on it. this could mount the motor perpendicular to the screw.
n1cod3mus (author)  heathbar643 years ago
I've actually changed my mind about using this in my former and i'm opting for a scissor lift type setup
espdp23 years ago
I like it. I have some ideas that could use that. What have you used it for? And roughly how powerful is it?
n1cod3mus (author)  espdp23 years ago
I havnt used it yet i was intending to use it to raise a vacuum platform for a vacuum former i was going to build but i have found another method.

i expect it could lift a fair weight as the motor is an 18v that came from a cordless circular saw.
zack2474 years ago
very cool!
n1cod3mus (author)  zack2474 years ago
thanks man, i'm sure there are ways to imporve on the design, i am still lloking at a way of gearing it so the motor is beside the shaft, but i cant figure a way using cheap materials where the gears wont give out to quickly.
If space isn't a problem, what about using bicycle sprockets and a short piece of chain? Heck, by using two different sizes, you could change the speed of actuation at the same time. You could also try stopping by a garage or photocopier repair place. Either should have junked strong gears that would do the trick.