The FAC Feeding Roller
Quest for the Holy Grail.
Now, what was that ?
Matarvalsen, or the Feeding Roller, was part of the original FAC system in 1952. It was used in the model of the gang saw illustrated on the cover of the contemporary FAC manual. But already in 1957 it had disappeared from the FAC catalogue - making it the most elusive of all FAC parts.
If you're missing the original thing you can make a fine feeding roller from a bunch of sprocket wheels.
But please never try to do the inverse!