After a week's neglect, I revisited the misaligned lowercase on my Olympia SM4 with the same hopes I might harbour returning to a baffling crossword clue.
The upper and lower stops for the carriage's vertical travel (see earlier post) were so hard to reach, I decided that their adjustment shouldn't be the solution to fixing the unusefully large amount of play problem on an otherwise pristine Olympus.
There were two sources of to-and-fro play in the carriage that I could see. One being the (unfathomable) shifting linkage, the other the bearings and the tracks the ball-races run along. I unclipped the carriage strap and spent a few minutes running it from side to side to see how the play might be eliminated. I'd assumed the two rails were part of the same pressing but when I got my magnifying glass out I could see that the rails were separately mounted and that the rail on the keyboard side showed a tell-tail knurled surface beneath one of the screws. An adjustment slot? Could be. After slackening the screws at both ends of the rail, I pushed each rail away from the other as far seemed practicable. I'd guess somewhere between 0.5mm and 1mm. Then I retightened the screws, adjusted the back rail stops (at bottom, see photo) and checked that the carriage still ran freely under ts own weight. It did and it worked! A few lines of type showed legible descenders on the lowercase where previously they'd been faint ghosts. The seven eighths is joy to behold!
|Both photos taken under a desk light, typing not scanned. PS: The slow bike ride happened - I lost - and I didn't suffer the indignity of the knobbly knees competition.|
So, if you find yourself with misaligned lowercase on an SM4 - maybe the above will help. I hope so. And thanks again to Robert and Mike for their helpful suggestions. Sometimes it is good to walk in the wrong direction before arriving at the destination.