Hey guys i thought i would share with you my way of turning my standard bench grinder into a variable speed Bench grinder. Things your going to need are.: 1 A Decent Dimmer switch, 2 A Outlet to pug into, 3 A double outlet box to keep it all in and safe, 3 A Old 3prong extention cord.
Ive now mounted this to my wood Bench Grinder stand. Over time you will more than likely have to replace the Dimmer switch (Because it wasn't Meant to take that kinda load). With this your 3500rpm can be turned down to a 1500rpm Grinder with ease. And saves you the cash of paying for one of the over priced Variable Bench Grinders.
Here is a pick of it