This is true, though I haven't come across a wound field wiper motor since the early 70's. Even in the 60's when they were more common we used to make ride on kids cars and animated Halloween decorations with them by feeding the field wires out of the motor. Plus when you go to the u-pull-it the wiper motors are easier to get to. Half the time they have the cars so close to each other it's hard to get the door open far enough to get to the window motors. (unless you can find a Saturn and then you can pop the plastic door panel off and get to the motor from the outside)
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Need a little electromics help
- Thread starter GrayTech
- Start date
This is true, though I haven't come across a wound field wiper motor since the early 70's. Even in the 60's when they were more common we used to make ride on kids cars and animated Halloween decorations with them by feeding the field wires out of the motor. Plus when you go to the u-pull-it the wiper motors are easier to get to. Half the time they have the cars so close to each other it's hard to get the door open far enough to get to the window motors. (unless you can find a Saturn and then you can pop the plastic door panel off and get to the motor from the outside)
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- Feb 13, 2017
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In the original posting, the user stated that he didn't know much about electricity. My suggestions were geared to that (lack of) knowledge level. If he knows enough to find a permanant magnet wiper motor, that would be the better choice because of the heavier worm gear internally. The suggestion for a window motor was intended to have him avoid a wound field wiper motor.
I have a '68 dump truck (small, C-30) that I'm working on electrically. It has a wound field wiper motor with internal connections. I can bring out all 5 wires, But I don't want a nonelectrical user to attempt that while in the middle of figuring out the mechanical portion of his project. Being helpful without over complicating things was my intent. He has need of a simple reversable motor.
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Yes, PC power supplies are good. If you want a new motor or don't have a junkyard nearby try monster guts, they have new ones for $27 each.
If you want controller ideas, check out some of the Halloween prop groups, they have all kinds of solutions for wiper motors.
On mine I just use a 6 amp battery charger (you have to use a cheap manual one, not a smart one). Between the 12v 6amp, 12v 2amp, 6v 2amp settings on the charger and the hi and low speeds of the motor it gives me 6 different feed speeds. My original plan was using the charger temporarily until I got around to making a variable speed control. I've been using it that way for almost 20 years now and haven't had enough issues with the fixed rates to motivate me to change it to variable.
If you want controller ideas, check out some of the Halloween prop groups, they have all kinds of solutions for wiper motors.
On mine I just use a 6 amp battery charger (you have to use a cheap manual one, not a smart one). Between the 12v 6amp, 12v 2amp, 6v 2amp settings on the charger and the hi and low speeds of the motor it gives me 6 different feed speeds. My original plan was using the charger temporarily until I got around to making a variable speed control. I've been using it that way for almost 20 years now and haven't had enough issues with the fixed rates to motivate me to change it to variable.
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- Feb 17, 2013
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Here's a relatively cheap DC motor speed controller. This plus a DPDT will get you reversible variable speed. I've used either this one or similar ones several times. They work well. Ebay will have lots more.
HiLetgo 12V~40V 10A PWM DC Motor Speed Control Switch Controller Voltage Regulator Dimmer for Arduino: Amazon.com: Industrial & Scientific
HiLetgo 12V~40V 10A PWM DC Motor Speed Control Switch Controller Voltage Regulator Dimmer for Arduino: Amazon.com: Industrial & Scientific
www.amazon.com
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- Feb 13, 2017
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My original thoughts revolved, and still do, around reversable motors. The (cheap) battery charger is an ideal solution. As well as wiper motors having the better torque curve and duty cycle. As long as the end user finds one with a Permanant Magnet field. An "X" axis drive will need to run in both directions on a regular basis, so this is a major concern. The supplier recommended above has reversable motors that would work.
Using a PC power supply may work, it would depend on the actual motor and the actual power supply. The simplist way to determine that is to hook up both motors with a moderate load and try to run both at the same time. The PC power supply will not be hurt, it simply goes into foldback when overloaded. Disabling the motors and a "Power on reset" will clear the power supply. If there is capacity to measure current, the motors can be tested under anticipated load before doing hookup.
Although the battery charger is an ideal solution, it should have a little capacitance on the output. While 1000uF per amp is suitable for many electronics, it isnt necessary here. With full wave rectification, such as the battery charger, the sine wave approaches zero at 120 times a second. Without a battery, it will reach zero. The capacitor only needs to be enough to prevent this. 100uF per amp will serve, although higher would be preferable. I have a number of 4700uF, 65 volt caps on hand. Such would do quite well, probably exceeding the capacity of the battery charger. Lower voltage would work, but my experience calls for 3 to 4 times voltage capacity.
The PWM motor speed controls I get from Marlin P Jones are rated at 30 amps at a nominal voltage of 30 or so. Quite an overload capacity for this application. Any reversing function would need to be on the output of the PWM. A relay is best as it can be controlled with one output. (Plus ground/return) A DPDT automotive relay is fairly common, giving Forward-Reverse. Better still is two Double Pole relays, giving Forward-Off-Reverse capability. This of course would require two outputs, with a common ground. Above is suggested Amazon as a source. Jones is a little cheaper. Both are representative of the generic price, cheap.
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Using a PC power supply may work, it would depend on the actual motor and the actual power supply. The simplist way to determine that is to hook up both motors with a moderate load and try to run both at the same time. The PC power supply will not be hurt, it simply goes into foldback when overloaded. Disabling the motors and a "Power on reset" will clear the power supply. If there is capacity to measure current, the motors can be tested under anticipated load before doing hookup.
Although the battery charger is an ideal solution, it should have a little capacitance on the output. While 1000uF per amp is suitable for many electronics, it isnt necessary here. With full wave rectification, such as the battery charger, the sine wave approaches zero at 120 times a second. Without a battery, it will reach zero. The capacitor only needs to be enough to prevent this. 100uF per amp will serve, although higher would be preferable. I have a number of 4700uF, 65 volt caps on hand. Such would do quite well, probably exceeding the capacity of the battery charger. Lower voltage would work, but my experience calls for 3 to 4 times voltage capacity.
The PWM motor speed controls I get from Marlin P Jones are rated at 30 amps at a nominal voltage of 30 or so. Quite an overload capacity for this application. Any reversing function would need to be on the output of the PWM. A relay is best as it can be controlled with one output. (Plus ground/return) A DPDT automotive relay is fairly common, giving Forward-Reverse. Better still is two Double Pole relays, giving Forward-Off-Reverse capability. This of course would require two outputs, with a common ground. Above is suggested Amazon as a source. Jones is a little cheaper. Both are representative of the generic price, cheap.
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Can you kindly share the part name for the varistor under the fuse? Mine was blown by the fusd and totally damaged, and i can't see the part name to replace it. I could only make out GNR 10---K. Appreciate your help!
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This is a remarkable thread. After you guys finish with this, I have a friend who has a small brain tumor, and I have a 1/2" end mill that will reach it. I just need some advice on how to stop the bleeding afterward. And maybe how to hold his head still. My vice only opens to 8".
I know, this is in poor taste. Sorry.
I know, this is in poor taste. Sorry.