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I have some spider props and I want to mount them in various places on wiper motors so they will move with the illusion of skittering up and down webs.

The possible issue I'm running towards is that automotive motors are not typically run off 120v ac. I know that people have done similar things with motors and props in the past, just seeing if anyone here has any advice or experience to share.
 

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Typically people are using a power supply to drop the 120V ac down to 12V dc or even 5V dc.
Most common is the small type used in laptops or LED strip lighting.... see attached picture:
You can even get a PWM. (pulse width modulation) to vary the speed from 100% down to very slow.
Be warned that the slower you go the less power or torque you will get.
719516
 

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The advantage of a 5V supply is it runs slow on the slow wire of wiper motor and that is what a lot of people want for spooky effects. Most wiper motors have two speeds built in. You avoid the expense and extra parts wiring etc of a PWM if 5V is the right speed for your prop.
719517

PWM's can be had for less than $20. if needed. See this chart for speeds on 5V and 12V:
 

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here is a link to a PWM :https://www.amazon.ca/dp/B00XBV7M0G/ref=dp_cerb_1
there are many available.... I like that these have an aluminum box... some are just the circuit board.

here is power supply I have ordered: 5 Volts dc 5 Amps:
you may find a bunch of these power supplies in a second hand store or ??? and can be cheaper...

I also recommend this as then you don't have to hack wires on power supplies:
they are nice and really simplify wiring hook up.
 

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I am in Canada .... so I don't find it cost effective to order from Monster guts.... shipping costs $$ to Canada.... but if you are in their shipping area..?
They sell all this stuff too and as a package with a wiper motor and supply and PWM and wiring.
I look for the free shipping if possible.....
I have a PWM on my Pumpkin man that turns his upper body and it is slower that the 5V supply.
For him it is better as I want a very slow movement.
But I tested the PWM on my swaying zombie and realized that it wasn't needed because 5v is the perfect speed. Any slower and he seems to bog out as not quite enough torque.
Same with the Witch stirring cauldron.... 5V seems like perfect speed.

Now if you are ordering a PWM.... at least the one I linked to on Amazon... you will need a 120V to 12V dc supply. That PWM won't work with only 5V input.... maybe others would?
 

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One last point... those power supplies are supposed to be "for indoor use only".
And obviously the PWM is not weather proof either!
Most people are putting them inside a plastic container like a Tupperware or a cheap dollar store one.
Just bring the wires out through a notch cut just under lid seam or drill a hole in the side and seal it with silicone etc.
If your spiders are indoor... you are good.
 

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Have a look at this video as he uses one motor to control several props and it might work for you..?
They will all move at different times as the crank pulls fishing lines attached to each prop.
 

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Have a look at this video as he uses one motor to control several props and it might work for you..?
They will all move at different times as the crank pulls fishing lines attached to each prop.
I was going to point that out. He also has videos showing how he sets up spiders that do exactly what the OP wants to do.
 

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You can even get a PWM. (pulse width modulation) to vary the speed from 100% down to very slow.
Be warned that the slower you go the less power or torque you will get.
This is a misconception with PWM. Unlike lowering the voltage (which does indeed lessen the torque along with the speed) PWM can lower the speed without loss of torque, hence the big advantage to using PWM.
 

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This is a misconception with PWM. Unlike lowering the voltage (which does indeed lessen the torque along with the speed) PWM can lower the speed without loss of torque, hence the big advantage to using PWM.
Maybe within certain limits.....
My personal experience with what I have is that slowing my Pumpkinman/watchman prop down any slower than I have it in video.... he stops under any load at all. even a slight binding of jacket on pants. So definitely lower torque in slower settings.
I have a PWM similar to the one I linked (exact one I have is not available now?)
Running a 12Volt 5Amp power supply and an older Chrysler wiper motor from junk car.
This brings up another point - used wiper motors from junk yard are hit and miss.....
Out of the 3 I bought - one was rusted solid - one is kind of noisy - one is good but rusty.
If you can get used ones for free.... OK. - then also get the wiring plug in too.

Just my personal experience..... you setup may differ...?
 

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for speed reference... this Zombie is running a 5V supply and then switches over to a 12V supply for "frantic mode" when the motion light sensor detects a person.

No PWM in this. Shows the difference from 15rpm to 35 rpm.
what effect are you after.....
 

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Maybe within certain limits.....
My personal experience with what I have is that slowing my Pumpkinman/watchman prop down any slower than I have it in video.... he stops under any load at all. even a slight binding of jacket on pants. So definitely lower torque in slower settings.
I have a PWM similar to the one I linked (exact one I have is not available now?)
Running a 12Volt 5Amp power supply and an older Chrysler wiper motor from junk car.
This brings up another point - used wiper motors from junk yard are hit and miss.....
Out of the 3 I bought - one was rusted solid - one is kind of noisy - one is good but rusty.
If you can get used ones for free.... OK. - then also get the wiring plug in too.

Just my personal experience..... you setup may differ...?
Well you have to keep in mind that torque (power) is speed related. So speed being consistant, PWM will yield more torque than simply lowering the voltage to achieve that speed. Also just an FYI, don't pay $20 for a PWM control, you can get the same PWM controllers on ebay for less than $5.
 

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[QUOTE="J-Man, post: 2535657, member: 39046" Also just an FYI, don't pay $20 for a PWM control, you can get the same PWM controllers on ebay for less than $5.
[/QUOTE]
You have to remember I am in Canada not USA.
It costs me 1.33 CAD for $1. US
And there is import fees into Canada or Duty....
So that $5. pwm on eBay will cost me more.
Probably $15. or so... if I order $50 of stuff.....
That is why we Canadians have to be wary of prices shown on eBay and Amazon.com
The reason I use Amazon.ca instead..... no surprise fees on delivery!
 

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You have to remember I am in Canada not USA.
It costs me 1.33 CAD for $1. US
And there is import fees into Canada or Duty....
So that $5. pwm on eBay will cost me more.
Probably $15. or so... if I order $50 of stuff.....
That is why we Canadians have to be wary of prices shown on eBay and Amazon.com
The reason I use Amazon.ca instead..... no surprise fees on delivery!
Not sure what your import fees are from China, in the US shipping from China on small items is usually free or very minimal.
 

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I stole a PS from and old computer tower that has both 5v (red) and 12v (yellow) and wired them up for USB. Boxed the whole thing in fenceboard and made water safe. Fan runs to keep it cool. Works great. I run a max of 4 props off it.
 

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In case this comes up, we confirmed last year that a 2 amp power source with a PWM drives a wiper motor just fine. The same power source without the PWM wouldn't work.

 
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