Makita 3700b diy speed control

This is a noob question, because I do not understand if this will work.
I was planning on using the makita 3700b mainly because its cost effective, but the rpms are locked at 30000 rpm, so what if I connect the main power output to a potentiometer to control its speed?
Like how one would control the speed of a ceiling fan.
Would it work?

A light switch dimmer is unlikely to have any desirable effect.

Take a look at this thread on a motor speed controller.

There are many reasons why speed control on an AC motor isn’t as simple as dimming a light bulb, and it’s not as easy as managing a DC motor either.

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A commercial fan/router speed controller like this one will reduce the RPMs. The more expensive speed controller claim more torque at a given speed. Don’t know if it is true. Also there has been both successes and failures using dimmer switches to control router RPMs. It depends on what electronics are used to implement the dimming. There are a few forum topics that explore dimmer switches.

But there is another issue with external speed controllers…no feedback loop. In a good variable speed router, the power to the motor is varied by the load to maintain a set RPM. But an external speed controller does not have a feedback loop, so the RPMs will be reduced under load. That doens’t make an external speed control useless, just not optimal. Note I used a speed controller for my DW660 before I switched to a router with a speed control, and I was happy with its performance.

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I have the speed controller linked by Robert and it does work well to control RPMs, but you do lose torque at low speed. I use this controller also to use my table router as a drum sander, and it becomes easier to bog down the motor when on low speed.

If you want to maintain torque at low RPMs, a VFD is a what you need. (Variable Frequency Drive). I am not an electronics expert, but I believe the cheap controls clip the voltage on the sine wave, while VFDs keep full voltage (thus torque) while controlling frequency for speed. I think this is like the AC version of PWM.