Please don't take this the wrong waybut...
I have a huge bee in my bonnet about grinding jigs

Think about your turning - you are turning beads, coves etc. regularly. Exactly the sort of motions needed to grind freehand!
All one really has to do is think of the grinder as a piece of wood

Add in a tiny bit of practice & the world's your oyster.
The money saved can be spent on beer

BTW - I draw the line with OT tools, where the use of the goniostat is usually an imperative, or with milling cutters/slot drills/drill bits.
Cheers,
Ruaidhrí