I'm going to try some surface grinding in my mill. It seems like a cup wheel is what I need. I have a magnetic "chuck."
What do I need to know about choosing wheels? My current need is to grind imperfections out of 3" x 3" 4140 square plates, sightly hardened (Rc ~40). I need toem to have a mirror finish when I finish the grinding/polishing process.
Thanx, guys.
What T just said.
EVERYTHING about a mill is a poor fit to grinding.
Planer can do it. Even an angle-grinder on the end of a shaper ram HAS done it.
But even so it ain't quite right.
Watcha doo is send stuff like that
out. To folks who HAVE a lot more than just the one grinder, a
whole lot more than just the one wheel, and a serious investment in chucks, dressers, dirt collection, through-wheel coolants, and a ton of fixtures for mounting the goods.
Did I forget to mention "experience"?
Because it s their Day Job. For more than just the one "day".
And only the competent AT it get to survive for ANOTHER day.
You can hire a small increment of that goodness under THEIR roof waaay cheaper than you can acquire even the tiniest part of it under yer own roof. Investment ain't the half of that. Learning curve is the killer of time.
Which isn't ordinarily all that costly, anyway.
Cheap enuf, more than one or two of us even start-off with stock bought that way. Already all-over Blanchard ground. Work it with care. De-burr. Pack and ship. Done. Go earn a crust on the NEXT job instead of f*****g around.
"Mirror finish"? If you plan to BUFF them? Sounds as if all yah really need for starting point is lumped under "Blanchard ground", whether the machine doin' it was made by Blanchard or never.
A true "Mirror" finish? A grinder is only the pre-prep anyway. Lapping makes mirror-grade surfaces. Tedious process. Very!
And even then? Ignorant SOFT steel ain't worth the bother of it.