I had bought this White Rotary 77, came in cabinet with accessories and manual at an auction back in the fall for a whopping $2.50. Around here people are afraid of old vintage sewing machines unless it's a Featheweight or older Singer. It seemed to be in great shape and taken care of over the years.
After get it home and pugging it in it worked except do to sitting the flat spot on the rubber was making it clunking nosie and sewing in different speeds when it would hit the flat spot. I believe I read here that to make sure the motor drive wasn't toching the wheel when not in use. Planned on ordering a new drive pulley but noticed there are several sizes, not sure which size I needed. So I had some left over batting and decided to in the mean while keep the pulley and wheel apart hoping not to cause any more indents. Well even though the rubber is hard and sure it due to it's age I noticed the dent was not as indented a few days later. Since then I still put the batting on when not using it but now the indents are gone, so while using it it has smooth out the indents. Yet I still need to get a new drive pulley with better newer rubber...just to figure which size. I don't have a tool around to figure out the measurment.