Thread: coasting time for grinders

Finally gave away my green grinding wheel that I bought about 10 years ago as I haven't used it since I added a diamond disc to the side of my first CBN wheel.

In the green wheels place I have put a second 200mm x 40 mm Vicmarc CBM wheel.

I've also rearranged the grinder attachments on the 2 x 1HP grinders that both run from one VFD.

Now I have the thin kerf abrasive cutting wheel mini table saw and Multitool Linisher on one grinder - this makes sense because the most common thing I do after cutting a piece metal is tidy up the burs on the cut piece by sanding.

The other grinder thus has 2 CBN wheels - the new Vicmarc CBN and a 6 year old 200 x 40 mm Woodcut CBN wheel.

The Woodcut was balanced using wobble washers a year or so back so I was interested to know how the Vicmarc would go straight out of the box. I haven't done any vibrational measurements yet but sof ar its seems pretty good. There is a bit of Vibe at about 48Hz but increasing the frequency to 52 Hz seems to dampen that out significantly. Eventually I will make the new wheel some wobble washers and play around measuring the vibe again

Another thing I notice is that the grinder with the CBN wheels now takes a lot longer to coast to a stop, 402 seconds to be precise. Now I know the Vicmarc CBN wheel has lot more mass around the edge than the Woodcut wheel but this seems like a long time.

I'd be interested to know what other folks get as their "time to coast to stop"