Hi everybody,

this Curta is my first one - it was given to me by my oncle, who owned it for a long time. He got it from a coal mine, where it barely was used. Its serial number is 11140.

Some time ago I determined that the clearing lever is screwed instead of beeing riveted. Also the screw on the knob is in a lower position which only the early ones had.

So how can it be?

I think this is an all original Curta... (and a very nice one by the way...)

The screw / rivet mounted clearing rings are not directly assignable to a range of serial numbers - but most of the earlier Curtas are screwed.

And the position of the screw is also a variation which is not explored now (...)

Hello Murff,

do you really think it's original?

My 5023 is also screwed and the screw of the knob is in the lower position, but my 8121 is riveted and the screw is not in the lower position.


5023


8121

Cranks and clearing levers are the most damaged and replaced parts on a Curta.
So it happens that a crank on an early Curta is replaced with a later type. And as I know the srewed clearing levers where always replaced with a rivet mounted lever.

So nothing wrong with your Curta...



except maybe the chrome crank?

in addition I checked some Curtas:

production date
-- clearing rings mounted with srew or rivet
-- knob on crank, screw position borttom or middle

February 1948 -- screw -- bottom
May 1948 -- screw -- bottom
November 1948 -- screw -- middle
November 1949 -- rivet -- middle
June 1951 -- rivet -- bottom
January 1952 -- rivet -- middle

so... also a mixed picture
but in general older Curtas have a screw mounted clearing ring and the screw position is at lower area of the knob - no exact serial numbers known...

Hello Murff,

thank you for your investigation, but you see, a Curta with S/N 11140 should be riveted.
Who knows what they have done at Contina - perhaps they had parts left of earlier production and reused them.

Please help ... [url]http://s1139.photobucket.com/user/juliogmz/media/DSC00747.jpg.html
[/url]http://s1139.photobucket.com/user/juliogmz/media/DSC00748.jpg.html

http://s1139.photobucket.com/user/juliogmz/media/temporary_3.jpg.html

murff wrote:

The screw / rivet mounted clearing rings are not directly assignable to a range of serial numbers - but most of the earlier Curtas are screwed. And the position of the screw is also a variation which is not explored now (...)

until now --- see the updated list: Curta Type 1 - Variations of Curta Type I

based on the recently acquired first Service Manual by Contina AG:

--- CURTA I Service Manual - Dismantling Stage E