John,
I wont tell you how I do it, but I will give you some clues, lol.
You need a surface grinding wheel ( the white ones) and lubricate them with a water soluble cutting compound.
A lubricant catching tank and recirculating pump.
The motor driving the grinding wheel needs to be able to change speeds to keep cutting speed the same as the wheel wears down.
I use an electronic variable frequency drive to do this.
You will need an adjustable "depth of cut" system to adjust for wheel wear.
A digital grain scale to check blade weights.
Its easier to move the grinding wheel across the blades clamped to a "foot print"base form. ( toggle clamps or magnetic chucks)
I bevel blades before fitting the ferrules( easier to clamp)
Straight edge blades are easier to bevel than curved designs.
Curved designs would probably require a seperate machine with a radial sweep to the cut.
The machine I'm alluding to, is pretty much my old one. I have a better machine on the go which will be ready soon.
It may be easier for you to buy a cnc surface grinding machine from an engineering supply. If you go this way, I would suggest a neomicro fine pole magnetic chucks, mounted on sine tables, to hold the blades down.
Google is your friend for looking at machinery
Whichever option you go for it will cost some serious money to set up.
Woody.