Surface Grinder Table Flatness

I needed to get the SG up and running to get some simple jobs done.
I figure I will learn a lot just using it, perfection can come later.
The table was tested as Ok with the DTI, the chuck cleaned like the table, and the chuck mounted not too tightly.
The wheel is 38A60-J, 162x11 mm, used without coolant at 2950 RPM.
Small sample pieces of MS and CI gave a reasonable finish resulting in <0.01 over 80x30 mm.
Very pleased with progress so far.
I am sure the only reasonable finish is due to my lack of experience.
Coolant is next to be introduced, and experiments with a coarser wheel and various speeds (VFD).

Testing surface plates against the straight edge should start in a couple of weeks.
John
 
Lot's (if not all) of good advice above...I "rebuilt" several surface grinders in the past including grinding and/or scraping in the ways (vertical; wheel head, and horizontal: table (whether rollers or not)...one thang' that seems to be missing above is after the mag chuck is ground and mounting is finished (usually by way of using another surface grinder) is the wheel used in the final grinding of the chuck...ifn a diamond wheel (about 220 grit) is not available, better make sure the "rock" wheel is proper and doesn't loose much when grinding (about .0002 a pass at finish then down to practically nothing (.00005) (a half tenth LOL) as yoose' get to ends (X) and the back then front of Y...Back and fourth front to back over and over until that indicator mounted (mag) on the wheel head housing or wherever, over the entire surface of the chuck reads .0001 or less!...Note: Sometimes grinding wet gets better results ("flatter") (and remember to let the wheel "normalize" with the coolant running on it a while) and sometimes dry (depending on the wheel)....as does sometimes and usually grinding that chuck with magnet on...Another note: When done and its nice, move the work pcs around on that chuck when yoose' can to avoid the dreaded gradual dip in the center that developes (this used to drive me crazy in a shop when it seemed everybody automatically set their parts smack in the middle of the mag. chucks day in and day out.
 
...I was just thinking (Hey! I heard that!)...another trick after dressing "flat" a good, hard (I liked some of the Norton pink) "rock" wheels is to lock or move those table stops together (for so no X table movement!) and plunge grind into a pc. of mild steel a little (think!, careful!, easy!, only the back side of the wheel into the left side/edge of the soft steel!!)...this takes off the loose "pebbles" and dust that are going to come off during the 1st pass or so on the table (or work pc.)
 
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