Understanding Grinding

Nice pics (Although in my grinding world (which was 90% hardened D2 or S7 tool steel and the various grades of carbide), .oo1 was a perty' heavy cut (on a small Doall or B&S to a "big" Kent), .0002 and then dwell (Universals and Blanchards) or "back over" or through (when surface grinding and C/L) with zero feed was my normal finish depth of cut...as for seeing some Machine Tool Grinders" glenb; Here's some googled picture links:

https://www.google.com/search?q=sur...X&ved=0ahUKEwj3gaSb8ozQAhXjyVQKHYCqBSwQsAQIGg

https://www.google.com/search?q=Uni...X&ved=0ahUKEwjd-9ai9IzQAhWorFQKHb1mCR4QsAQIGg

https://www.google.com/search?q=cen...X&ved=0ahUKEwjPr5bC9IzQAhXLgVQKHW59AWgQsAQIIQ

https://www.google.com/search?q=bla...X&ved=0ahUKEwivprKP9YzQAhXLi1QKHTNQCIQQsAQIGg
 
Add: My "lead in" dress on "rock" wheels and diamond wheels (angle?) for just flat surface grinding and straight Universal grinding was usually about .003 with the "big" (+.003 or so) diameter of the wheel at the front (surface grinders) or to the left towards the headstock (facing the machine) (Universal grinders).....therefor I only fed down (or in) on the proper side thereby preserving the lead in and "sharp" front edge of the wheels (when called for)....Cheers!
 
Another note! (Blab) (LOL): For the home shop, finding a used midsize Universal grinder (ID/OD) will be probably the hardest and most expensive Machine Tool on a list to find (even used EDM's will be cheaper)...I once cut a purchase order for a new midsize "manual" Kellenberger (over $100,000.00 !!) and the Co. turned it down and went for a $60,000 Tshudin...Seeing these pictures I see and reminds me of the 3 small Myfords (British) we had plus a Big B&S and a huge Landis...all these Grinders I'm listing were built like "battleships" (brute castings), were (are) 50 + yrs old, and still grinding day in/day out holding "half tenths" (.00005)...But the most accurate, most expensive ($180,000 used) Machine Tool I ever ran or had anything to do with was a grinder (A Moore Continuous Path CNC (GE Control) Jig grinder (The Moore bros. (Herman), way back before even I was born (LOL), invented the"tenth" (.0001) as applied to an actual machine and results)
 
just to set the record straight lapping gives a far superior surface finish to grinding. yes the wheels wear. that's why grinding is such a slow process(among other things) but grinding is lots better than milling. bill
 
Yes, Dumore toolpost grinders are the most numerous around or make one for a good project....but best is to rig up a vacume while grinding or at least cover as much as you can during grinding and good cleanup after... as the fine grinding dust can wreak havoc with your lathe surfaces (the grinding "dust" from wheel wear and the stock being ground acts as kind of a dirty lapping compound, especially on the ways when its trapped under the carriage (etc)
 
....and yes Bill I see where you're coming from...I have a small lapping plate I have charged (smeared) "blue" diamond paste on here at home ....on the job we had a couple with blue and "pink only" charged on them for "mirror" finish/polish (2rms or less)...
However, say and depending on yada yada; A 900 to 1200 grit diamond wheel and some fine (some "blue" wheels we had come to mind) "rock" wheels don't leave too bad of a finish (I have gotten down to 8rms with these wheels on carbide and toolsteel (for various Armor tooling (up to about 12" x 12" flat punches and ejectors) that the prints called out 8rms or better and we got them down to 6 right off of Surface grinders...the trick (to pass surface inspection (avoiding scratches) was to knock off any loose "pebbles" (LOL) with just fine sandpaper or scotchbrite from the spinning wheel after dressing the "rock" wheels and make sure the coolant filter was keeping out "loose rocks" in the coolant to the head plus we would rig up secondary fine screen right at the coolent spraying onto the wheel/part
Add: When cylindrical grinding with any fine wheel I still always left around .0002 polish stock on all ODs and ID's...
 
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So safe to say no matter how rigid a lathe you have you cant get .0001 with a toolbit? It'll just rub and not cut?
 
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