Will a Router Speed Control work with a Bench Grinder

Dec 06, 2004 18 Replies

I see where router speed controls sell in the $25-$50 range and supposedly they will work with most routers that aren't soft start or already have variable speed. My question is what is chance of this working with a $40 6 inch non-variable speed bench Home Depot Ryobi grinder.... I would like to use this grinder to sharpen lathe chisels and I need a slower speed grinder for this.



-TIA


Probably will not work "well" at all. The speed control's work on universal motors vs. induction motors. More than likely the grinder has an induction motor.

They should work with any universal motor as long as the current rating isn't exceeded. One problem you might encounter with a grinder is the relatively slow start up speed compared to a router and the possibly resulting high current draw. I used one with my old PowrKraft RAS which had a univeral motor when I was using the high speed aux spindle for shaper cutters.

-Doug

Your grinder does not use a motor with brushes so the speed controller will not work. There are many "High End" woodturners sharpening their chisels on cheap high speed grinders without problems.

AZCRAIG

IIRC Ryobi makes a 1750 rpm grinder. Probably not the cheap one.

The fastest way to improve the sharpening ability of a cheap grinder is by replacing the wheels. Check out the Woodcraft, Lee Valley and such catalogs and pick up a less aggressive grinding wheel. Less honing to do afterwards as well.

You still need a very light touch and a can of water handy, but changing the grinding wheel will cost less than the speed control and probably give you better results.

--RC

You can tell a really good idea by the enemies it makes

won't work. Just buy a white or pink stone.

-Dan V.

AZCRAIG...... Does a Ryobi benchtop belt sander use a motor with brushes??

Yeah, I already have a white wheel on it. I am sharpening some cheaper HSS chisels so I was told not to use water.... I am not an expert here so just following directions. Thanks for your time.

Buck, Who told you not to use water with HSS chisels? When you need to sharpen them, you must keep them cool when grinding. Frequent dips in a cup of water will prevent the chisel from overheating. Water will not harm the chisel in any way.

Dave

If it's loud like most vacuum cleaner, it has a universal motor.

AFAIK, I've not seen a gr> AZCRAIG...... Does a Ryobi benchtop belt sander use a motor with brushes??

to clarify: do not dip HSS in water when it is very hot. use a light touch on the wheel and dip it frequently before it gets hot, to keep it cool. if you do manage to get it hot enough to blue the edge, let it air cool a bit before dipping it.

They won't work with an induction motor, which most grinders have.

For the same power, induction motors are cheaper. For the same torque, or at slow speeds, brush motors are cheaper. So something like a grinder or DC that needs minimal torque will generally be induction.

Dave.... Seeing that I am not an expert in this area I have read lots of different articles on the web, many of which say there is no need to use water with HSS chisels. Most of them say to just let them air cool and not shock them with water when they get hot...... I don't know if this is true or not but a lot of experienced turners say it is true. I suppose if you use water right from the start your chisel will never get hot enough to damage it.

-Differnt strokes for different.......... me guesses

On Tue, 7 Dec 2004 19:06:07 -0700, Andy Dingley wrote (in article ):

Also, for a given power Induction is bigger and universal is smaller. Not many hand held tools will use an induction motor.

-Bruce

I guess I was not clear enough when I said "you must keep them cool when grinding". That is the precise reason machine shops run coolant continuously when cutting. Since most of us do not have that capability, frequent dips will have to do.

As for fixing the inevitable bluing, a dip in cold water then carefully grinding off of the entire blue area will not change the hardness or temper of HSS.

Dave

If they are real high speed steel, heat will not bother them.

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required