Speed Control

[Halfathumb]

Will a speed controller work ok with a Ryobi 8" bench grinder? I want to order a CBN wheel for sharpening chisels and lathe tools.
Any experiences, comments etc.?

Thanks 

Jim

[fredhargis]

If you refer t one of those controls like they sell for routers, it probably won't work. They are made for "universal" motors (have brushes in them). Your grinder likely (probably) has an induction motor.

[Halfathumb]

If you refer t one of those controls like they sell for routers, it probably won't work. They are made for "universal" motors (have brushes in them). Your grinder likely (probably) has an induction motor.

Thanks Fred. I guess I have to come up with a plan B

[hcbph]

If slowing down the spindle is your object, have you considered a 3 phase with a vfd?  I'm not sure how slow you're planning on going but this might be an option.

[Halfathumb]

If slowing down the spindle is your object, have you considered a 3 phase with a vfd?  I'm not sure how slow you're planning on going but this might be an option.

What is a vfd?

[Cian]

What is a vfd?

https://youtu.be/g7jFGOn6xfU?t=47

[kurt18947]

If slowing down the spindle is your object, have you considered a 3 phase with a vfd?  I'm not sure how slow you're planning on going but this might be an option.

I don't see a way to retrofit that motor to make it 3 phase. Unless the motor is 3 phase a VFD is not practical. Possible? Maybe, I seem to recall that it's possible to use a VFD on single phase. Practical? Probably not.

[hcbph]

Sorry, figured people understood: take a 3 phase motor device; add a vfd to it and you can run it off regular single phase 220 and most vfd's have a speed variable setting to it.  If nothing else, take a look at some of the VSR lathes.  You can vary the speed of the lathe with a simple twist of the knob.  If the OP had access to a 3 phase grinder, add a vfd then he could vary the speed of the wheels at will.

[Roly]

Sorry, figured people understood: take a 3 phase motor device; add a vfd to it and you can run it off regular single phase 220 and most vfd's have a speed variable setting to it.  If nothing else, take a look at some of the VSR lathes.  You can vary the speed of the lathe with a simple twist of the knob.  If the OP had access to a 3 phase grinder, add a vfd then he could vary the speed of the wheels at will.

Wouldn't it be cheaper to buy a slow speed grinder ?  The other issue is heat in the motor.  The motor cooling fan is not going to push as much air running slower.   Roly

[Pirate]

Put wheel in lathe and sharpen.  I chuck wheels in my Shopsmith 10er, to sharpen chisels. Being able to slow down speed is nice