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What's the best technique for using slitting wheels in the surface grinder?

While mostly in eKretz's camp in terms of action, it does seem that many here use heavier cutoff wheels than I have- I had .040 diamond for carbide and .030 A/O for ferrous stuff. For feed, less aggressive feed with the diamond cutoff obtained better wheel life, and with the conventional, you really had to watch heat buildup since once the cut started to close in, the wheel would begin to flutter or ripple, then game over.
And yeah, mounting those thin unreinforced wheels needed care. By comparison, .060 and heavier widths were far more tolerant of miscues.
Slitting (parting) wheels need to be darn tight (with blotters) because they are usually hard and so put more pressure to holding...As tight as you can with a hand on the standard wrench 6 or 7" long for a 7 or 8" wheel.

Parting wheel are Ok at surface grinder RPM, but if a lot of parting is to be done often a higher RPM will/may increse wheel life..but one may need better gaurds for is they break.
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I tried the cutoff on 316 stainless today. The 2x3x3 stock was clamped to an angle plate that was tapped ¼-20, but it seemed adequate. The cut went well until it was 1.75 deep, then the stainless started pinching the blade, had to stop and finish on the bandsaw. My grinder is a Harig 612 without coolant. Coolant might have made a difference.
Good suggestion. Need to look for the right tooling, isn't that always the excuse? Something like a drilled and tapped plate or a t-slotted plate would have made that possible. Had to make do with a 6x3x2 angle plate.
We ALWAYS set up round parts to cut off in the whirlgig/spin fixture. Told one of my new employees to do that one day and he thought I was crazy. It was a hardened 1 inch diameter pin and he had broken numerous cutoff wheels trying to get thru it, usually with pretty spectacular results. I stuck the pin in a whirley gig, started the cut slow to get the wheel cutting true, and then proceeded to crank it down pretty fast to cut off the pin in less than half a minute. The look on his face was priceless, but not as good as when I took it out of the collet and handed it to him!!!!
I'm in the camp of start out light cut, traverse or spin until the slot has been established.
From there i either spin steadily while downfeeding as fast as seems prudent.
Or set the table auto traverse, and ditto.

This allows the thin wheel to establish itself. Too easy in much work for small influences including heat to gradually veer the wheel if full depth taken and slow feed. Also, much work warps or releases stress as it parts. Small infeed as the wheel constantly re-travels its established path allow it to grind intruding metal and maintain that established path. Mostly. :) I do what Buck says and flip long work using a couple pins or short parallels against the rail to avoid parting through to the chuck. Also an end stop. Reason for spacers to rail is that most long work will spring somewhat, too. The spacers establish position but allow some sideways warp. magnet holds it. end stop prevents creep if part starts to warp up off chuck. I use heavy mist coolant on this grinder, flood on the larger grinder. Nozzle pulled out of the way for photos.


(Cutting 50 taper off rubberflex chuck, to rebore for Hardinge 4deg taperlock so as to have full 1-1/4" through spindle.)
(The cut went well until it was 1.75 deep, then the stainless started pinching the blade,)
not uncommon for heat/burn at the depth of cut to suck the width tighter..good that you noticed that. happens more with SS more than other materials.
Parting wheels are great to cut off a slice to reduce grinding time.

We had one HSS parting blade that the wear land could be cutoff with a parting wheel, and then go back to its job with not sharpening, even though I thought that was a poor practice becaus grinding .005 gave better tool life...
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