I have 3 bench grinders, an Elu which is 30 years old with a white wheel and a Sorby finger nail jig one side and a grey wheel and homemade angle jig the other. I have a B&Q 6" grinder with a light grey,fine, stone with a homemade angle jig that I use for bowl gouges and parting tools and a dark grey stone with a Sorby jig that I use for everything else, apart from my skews.
These I hone(yes hone) on the 3rd B&Q grinder that has a rush wheel one side and polishing wheel the other and rotates backwards.
The bee I have in my bonnet is this:- A well know company tells us we should use their water cooled machine when replacement stones cost the earth and only the first 1" is useable after that the stone is too soft. Another well know company tells us we need to use a 40mm, slow running grinder with a white/red/blue wheel that costs the earth. Another well know company tells us we need to use a belt to get the best edge ever. Now I know they would not make them if there was not a demand for them, but sometimes I think they are creating the demand, a bit like chisels" buy this one it will make you a better turner!"( don't get me started on chisels) My widest wheel is 1" wide and that is for the finger nail grind the others are only 5/8 to 3/4 wide,the wheels on my ELU grinder are the original wheels, so they are 30 years old and still with loads of life left in them.
When I teach I show my students how all they need to do is refresh the edge rather than grind 1/2 " off at a time, I show them that you can still sharpen a tool without buying expensive gear, the B&Q grinders were 12 quid each when I got them so I got 2 and they are giving stirling service.
So my advice is this,sharpen your tools as you use them and not just on a Sunday morning, make or buy jigs so that you get repeatable grinds and just refresh the edge,1 or 2 sweeps is all that is needed. Never grind on the side of a wheel and every now and then dress the stone gently and without losing too much off of it.
Rant over
Regards
John BHT