Shop OBEX P1 Docs P2 Docs Learn Events
Cheap linear actuators — Parallax Forums

Cheap linear actuators

WolfbrotherWolfbrother Posts: 129
edited 2013-06-27 17:30 in Robotics
Does anyone have a source for some cheap linear actuators that they have used with a stamp? I need to use some that go from 0" to 12" or so. Searching around, most of them seem to be used for customizing cars, but I'd like to use ones that have a sliding carriage so I can easily mount a couple of servos and some other things·onto the sliding carriage as well.

Thanks in advance.

Comments

  • lincolnlincoln Posts: 23
    edited 2009-06-05 20:27
    you might look at mcmaster carr. they have liner slide components. you can also make a lead screw form all-thread....
  • W9GFOW9GFO Posts: 4,010
    edited 2009-06-05 23:31
    Not real cheap...

    servocity.com

    Rich H
  • CounterRotatingPropsCounterRotatingProps Posts: 1,132
    edited 2009-06-05 23:32
    > a lead screw from all-thread...

    yup, just what I'll be using for moving a telescope ... scabbing a lead screw onto a stepper motor using a spider coupler ... a very simple mechanism.

    Wolfbrother, how much wieght will the carriage have to move?

    cheers,
    - Howard in Florida
    ~~~~~~~~~~~~

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    No matter how much you push the envelope, it'll still be stationery.
  • WolfbrotherWolfbrother Posts: 129
    edited 2009-06-06 15:09
    The actuators only have to move the weight of the standard Parallax servo motor and a couple of pens. Like a large scale linear printer. I was kind of hoping there was a cheaper solution out there than something like this: http://www.firgelliauto.com/default.php?cPath=104
  • kwinnkwinn Posts: 8,697
    edited 2009-06-06 15:36
    If you don't need high precision why not build your own? Two pieces of metal tubing, a toothed belt, 2 pulleys and a stepper motor.

    Also, if you have a supplier of used/surplus equipment nearby an old printer or plotter carriage would probably provide what you need.

    Another option would be the slider assembly from a ceramic tile cutter and the belt, pulleys, and stepper.
  • DJSandbergDJSandberg Posts: 56
    edited 2009-06-07 04:46
    Wolfbrother,

    How about a car window regulator?·

    Most of the car manufacturers have moved to the cable driven door windows.· They fail regularly.·· The usual part that fails is the cable, which is relatively easy to replace.· But the motor and slider is part of the regulator, so the entire unit must be replaced.

    When the dealership replaces the regulator (what the part is called that moves the window) under warranty, they usually have to keep the scrapped part for a month in case the manufacturer wants to examine it.· After that it's junk.· I probably throw out 30 a month.·

    If you are willing to·spend 30 minutes and $2, you could repair the window regulator.· The motors are quiet and powerful.· And free.· The rule is that the parts that are replaced under warranty can never be used in a car again, but I've had no problem using them for robots.

    A box of donuts or bagels and you can get an endless supply of motors.

    Daryl
  • CounterRotatingPropsCounterRotatingProps Posts: 1,132
    edited 2009-06-08 21:25
    Daryl,

    thanks for this cool, insider's tip.

    what $2 parts need replacing?

    - Howard

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    No matter how much you push the envelope, it'll still be stationery.
  • WolfbrotherWolfbrother Posts: 129
    edited 2009-06-09 01:20
    I think the regulators are a good idea as well, I'll give them a try. I'm not too sure about the repeatability of them in terms of positioning versus a linear actuator with a screw drive, but if they work you just saved me several hundred $.

    Thanks,

    Dave
  • DJSandbergDJSandberg Posts: 56
    edited 2009-06-09 03:28
    Howard,

    The cable is the part that must be replaced.· It's 1/16" aircraft cable and you can get it at Home Depot or a hardward store.· If you chose to use just the motor and not the rest of the regulator, you can have a great motor to drive a 10-20 pound robot.·

    You might also find power seat motors and·power mirror motors.··I've got a·doggy door running off of a sunroof motor and track.· Just ask the parts manager to put anything that looks like a motor into a box and you'll pick it up in a week or two.· It will save them a trip to the dumpster.· And remember, donuts or bagels.

    If you go on Ebay and search Toyota window regulator you'll get over 1,000 hits.· This will show you all of the designs that are available.· Ford, Chevy, Chrysler are all about the same.· So if you don't want to get a warranty one, you can get one on Ebay for not all that much money.

    Daryl
  • AmitchAmitch Posts: 1
    edited 2013-06-20 12:45
    Wouldn't hurt to check out www.progressiveautomations.com if you haven't already. Lots to choose from, you could save a few $$ on used items. (Stock Pending) or even look into getting custom actuators.
  • StempileStempile Posts: 82
    edited 2013-06-27 17:30
    DJSandberg wrote: »
    Howard,

    The cable is the part that must be replaced.· It's 1/16" aircraft cable and you can get it at Home Depot or a hardward store.· If you chose to use just the motor and not the rest of the regulator, you can have a great motor to drive a 10-20 pound robot.·

    You might also find power seat motors and·power mirror motors.··I've got a·doggy door running off of a sunroof motor and track.· Just ask the parts manager to put anything that looks like a motor into a box and you'll pick it up in a week or two.· It will save them a trip to the dumpster.· And remember, donuts or bagels.

    If you go on Ebay and search Toyota window regulator you'll get over 1,000 hits.· This will show you all of the designs that are available.· Ford, Chevy, Chrysler are all about the same.· So if you don't want to get a warranty one, you can get one on Ebay for not all that much money.

    Daryl

    I was looking for a windows motor and regulator to be the steering control of my PowerWheels toy car project. Found that U-Pull-It places were not cheap and more work. Searching for alternatives I found one on Amazon new. It was $36 and free shipping. U-Pull-It in my area wanted $35.
    Looked good when I bench tested it. However running it no load continuously, within 30 seconds it got HOT. I took the controller + POT parts from a servo motor hooked to a RC receiver and hooked that to a motor driver for PID loop control. Worked, but it was really hot quick. I was digging around on FIRST related forums given that FIRST KOP includes window motors, seems there are mixed reviews with same issue.

    I had a Lesson learned about the regulator cables and why I think it would be hard to fix used borken regulators. I took the slider off and just had the cables. Given how the cables wind inside the motor attachment, if a cable slips out of the grove or doesn't perfectly wind around the spool (several times) as it would with tension, it causes a lot of damage. When bench testing the cable part it got all tangled up. This one was all plastic so the groves were shredded and there were no screws. All tightly press fitted together. Trying to get at the spool to free the cable was near impossible. In the end I junked it. I see why the deals replace the whole thing.

    I still need a motor setup for my PowerWheels project...
Sign In or Register to comment.