Posts: 1,788
Threads: 36
Joined: Aug 2007
Oooh... big mistake. The heads were glued in at the factory and were never meant to be removed. The only way I know to set the height is to place a card in the mechanism and let the head rest on the card. The head must touch the card but not be so tight as to impede its movement. One problem is getting the head square to the card. If it is slanted then you can get read/write problems. I had a reader that with a loose head and it took quite a bit of playing around to set things right, but it can be done.
The nylon balls are used as part of the card detect/head switches. As the card slides over the balls they press on the gold leaf springs that then make contact with pads on the back of the keyboard. The three main switches are card edge detect (motor on), write protect detect, and head enable (a delayed version of card edge detect). There is a fourth switch that I don't beleive is used for anything.