I purchased a near mint Curta II recently (my first) and am having trouble operating the reversing lever. It is in the "normal" up position, but I am unable to push it down. Having never operated one before, I am reluctant to push harder in fear I might break something.

Any suggestions from the Curta brethren...

Well, I got it to move, but not sure how/why...

I tried several combinations of lifting/turning the carriage and lifting/retracting the operational handle. After quite a while, all of a sudden, I was able to easily get the reversing lever to drop down.

However, then I could not get it to switch back up! I then tried several more of the moves described above, and just about when I was going to give up, I was able to get the reversing lever back to the original (up) position.

Now I am afraid to try moving it down again

I would still like some comments from others on what might be causing my sticky reversing lever.

... it's difficult to estimate your issues of operations without having your Curta in the hands!

For both of your descriptions there are two possibilities...

Best case - it's an operation issue: please ensure that the Curta is in its ready for use position (the crank must be snapped in) at every change of the reversing lever or for operating the clearing ring...
Clearing should be possible 360 degree or between the two snapping points - in both directions CW or CCW. And, you cannot clear a register twice - it should be set all digits to zero after the first run...







Worst case - your Curta is defect: some parts inside are bent or jammed so that the initial state is not possible as it should (or only in some cases - depends on combinations of the operation).

Thanks so much for the insight. Both issues were due to operator error. I had not fully placed the Curta in the "ready for use" position when trying to move the reversing lever.

I still have questions about the CW/CCW rotation of the clearing ring that I will post in the other thread...