[BILL WILLIAMSON]

I worked part time for a clutch rebuilder, sometimes a disc will cause a chatter until it gets "smoothed" over with a little use. Sometimes there might be a slight thickness discrepancy in a spot on the lining.
Chattering on take off can cause high & low spots on the lining. Minerva chattered BAD in LOW. Second gear take off DIDN'T chatter. For a month, I took off ONLY in second, I "think" that evened out the HIGHS & LOW spots. After that, smooth as glass on LOW gear take offs.
On cars where, after humid storage, the steel "threads" in the disc & the flywheel rusts together & the clutch sticks, like locked up! After breaking it loose, the clutch "might" chatter. I "think" the second gear take off, "might" help smooth out the flywheel & disc surfaces & eliminate chattering.
It's a DAMN site EASIER than puttin' in a new clutch! Clutch chattering is fairly common on Model A's & sometimes, by experimenting, you can learn to take off, "chatter free", like, take off at idle speed, in low, THEN gas her up & GO!!!
I once put a SOLID center disc in my Nailhead powered, '53 Studebaker, DON'T EVER DO THAT------------------MAYBE YES, ON A RACE CAR.
Bill W.