Linear Actuator

Catlas · 02-06-2001, 09:37 PM

This doesn't actually apply to mp3 players but im gonna ask here anyways. I'm trying to put my sub box on a track so than it can slide into my car when the back seat is down. (Giving me accses to the spare tire in the trunk. Ive got that part all worked out. But I want to motorize it. The only linear actuators I could find to do this cost around 300-400 bucks...more than i have to spend. So does anybody know of a way to get one cheaper or maybe an alternative?

Catlas

P.S. I'm looking for 12 or more inches of travel.

Weston · 02-06-2001, 09:48 PM

I've heard that you can use a power antenna motor. I think they are pretty cheap new, but you could probably canibalize one from a wrecked car in a junkyard for next to nothing.

They only problem I see is if your box is heavy, the power antenna motor won't be powerful enough to move it.

Aaron Cake · 02-07-2001, 10:40 AM

As long as the box is on rails, the power antenna will be able to move it. Those things are pretty beefy.

Also, look into a power windows regulator. They are available cheaply at any wreckers, and have enough power to take off your finger.

------------------
Aaron Cake
London, Ontario, Canada

Player: Cyrix 200, 32MB RAM, 10.2Gig Quantum HD, Onboard EtherNet/Sound/Video, Custom Lexan Case, Arise DC-DC, Win95 Kernal w/Custom Player
Car: '86 Mazda RX-7 w/Basic Performance Upgrades

02-07-2001, 11:14 AM

You may be able to find a worm drive a lot cheaper than that too. Although it would be slower than an actuator.

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My DIY sub page

Scrapez · 05-16-2002, 01:06 AM

Not sure if you ever found something that would work for this but one of these might do the trick nicely:

http://cgi.ebay.com/ws/eBayISAPI.dll...tem=1352313759

-Jesse

albysure · 05-16-2002, 09:31 AM

i agree with aaron. get yourself a nice ball bearing drawer slider (they are available in pairs or one for underneath, get a full extension slider) and with any window motor you have a great motorized drawer.

to make sure you don't pull the drawer out too much, install a small switch somewhere at the end of your drawer travel to cut the power. then do the same to bring it back in.
i dont remember what you call the switch. it has a small metal piece over the button which makes contact when the drawer is all the way out. you'll need a double pole double throw switch to control the drawer reversing the opposite sides for the motor in and out directions. the motor is wired to the center poles.

Ces///M3 · 05-16-2002, 04:40 PM

power antenna moving 50+ pounds? I doubt that will work effectively/reliably

Aaron Cake · 05-17-2002, 08:06 AM

You need to remove the antenna, and simply use the retracter mechanism. It's usually a long plastic gear that is wound around another....It's quite strong, but don't abuse it.

albysure · 05-17-2002, 09:34 AM

"It's quite strong, but don't abuse it."

...sounds like a talk my father had with me sometime ago...

Ces///M3 · 05-17-2002, 01:33 PM

As someone who works extensively with actuators, I will once again say, that this will not work effectively

Aaron Cake · 05-18-2002, 09:28 AM

As someone who has used Cadillac power antennas to open doors, drawers and animate Hallowe'en creations, I say it will work quite effectivly.

However, there probably are better choices in actuators.

Ces///M3 · 05-19-2002, 09:35 AM

If it does even move the subwoofer box (which I say weight 50 pounds easily, not counting the rack and such), it will move it at .5" per second

ShinkunoNamida · 05-19-2002, 09:59 AM

If you have really good rails and you keep them well maintained it shouldn't take much of any force to move it.

Once you get the thing in motion you only have the frictional force.. frictional force on a good set of rails should be neglegible to the actuator. (object in motion stays in state of relative rest or motion unless acted upon by an outside force sort of thing.. physics is your phriend)

edit:
Oh yeah.. this means i think it will work just fine as long as you have a nice smooth moving set of rails

Ces///M3 · 05-19-2002, 10:29 AM

Im tired of arguing this topic, Ive done it extensively... For this to work effectively as in show car status, he is gonna need one or two heavy duty actuators, now if it wants to be ghetto rigged like alot of other things I see out there, then he can use whatever else he choses . If you chose to take this serious, go to mcmaster.com, they have every type of actuator youd want

Rob Withey · 05-19-2002, 11:47 AM

Quote:

Originally posted by ShinkunoNamida
(object in motion stays in state of relative rest or motion unless acted upon by an outside force sort of thing.. physics is your phriend)

Gravity is an outside force. Make sure you don't park on a hill.

Rob