Dating curta calculators
Dating curta calculators - koreans dating blacks
Lift out the brass carriage retaining bush and then the carriage pressure spring and set them safely aside.
When reinstalling, remember first goes the thin brass washer, next the spring, then the brass bushing with the larger opening end down and lastly, the snap ring.
This view shows the rounded head of the taper pin which is the larger end.
Pin punch and block You need to support the crank handle on a block while tapping the taper pin out.
On the other hand, if you've got the right tools and feel comfortable using them, you may enjoy opening yours up for a closer look to better appreciate the inner workings of this amazing mechanical wonder.
It actually isn't that difficult, as long as you have the right tools, take your time and know when to stop.
Remove bush & spring With the circlip removed, carefully lift the carriage, but keep your hand over the top of the calculator to catch the brass bushing and spring in case they spring free suddenly.
You may need to lightly tap the shaft while you're holding the carriage up to free the retaining bush.Also notice how the detents hold the desired input value in position.Imagine how complicated the machining operations are to create these spiral grooves and detents for these shafts!Carriage locking ball Before you go any further, be sure to remove the tiny carriage locking ball and set it aside for safekeeping.This ball bearing is what allows you to lift and turn the carriage or turn the crank handle or lift the crank for subtraction - but only one of these operations at a time.Carriage close up A closer view of the pinions, digit wheels, and carry pins for the carriage digits register.