Crooked frames in a Barnack?

I've had this problem for years and have read modern film cassettes are 2-3mm shorter causing the image to slant and/or intrude into the sprocket holes in early Barnacks and clones. With a packet of
 stick-on green felt pads sitting in my drawer, I stuck one in the base plate lock and it worked! I did it to all my Barnacks which had this issue.


Not my original idea, credit should go to this post.