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Drill trigger replaced with on/off switch and variable speed switch?

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As this will be my first post please take it easy on me🤣


I am doing a DIY project involving a corded power drill motor that I would like to mount horizontally. I was wondering if it would be possible to mount an On/Off switch along with a variable speed controller, such as a light dimmer to replace the trigger mechanism. 

First off I have found some videos showing the dimmer idea on youtube used for drills and dremels. But this is achieved by locking the drill trigger all the way down and then adjusting the knob to the speed desired. 

I would like to replace the trigger with just an on/off switch if possible or is it even safe. 

Any help would be much appreciated. 



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Maybe... not sure where they get them but for decades many large circuit breakers (1000+ A ANSI style draw outs in cast frames) use Ryobi drill motors to charge up the spring mechanism,

But be aware of what happens when you do what you describe and this goes for the speed adjustments on the drills. Most of the older ones used a brushed “universal” motor which is a DC motor. Adjusting the DC voltage adjusts the speed but the magnetic field comes from permanent magnets so torque is fixed. The AC is usually left alone.

A lamp dimmer uses a device called a TRIAC or two SCRs. When the AC wave goes through 0 A and this is key it turns off. The circuit detects the Voltage (not current) zero and then based on a timer fires a pulse that turns the TRIAC on. By manipulating the timing you get a from 0 to 100% of a chopped wave. On a resistive load like an incandescent or halogen load you get light dimming down to about 25% then rattling filaments from 25% to 0%.

A motor, particularly a DC motor though is highly inductive. The dimmer will fire to turn it on but because inductive current severely lags voltage it does not turn off like you expect and the effect is also load dependent!

Suggest you look at KB Electronics or Automation Direct. A small cheap real DC or AC motor controller will run about the same price as the lamp dimmer. Plus you can use very cheap small AC or DC motors without having to Frankenstein something with a drill and the cost won’t be much.

Or you can look at Vex or the FiRST Robotics retailers that sell high performance servo controllers for under $100 and motors for half that.

Sometimes scrounging just costs you money and time in the long run when you can buy the real stuff so cheaply.

Sent from my iPhone using Tapatalk

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