The Curta.org Bulletin Board

[Nigel Fraser Ker]

I have just bought Curta Type I serial number 68672

From the article by Daniel Ford it seems that this was produced in 1961.

I think it has a plastic crank and clearing ring which, according to things I have read on the Internet, first appeared in the mid-sixties.

What do you think? Was it produced in 1961? Would it then have been fitted with plastic bits? Or have I got the date wrong?

Any info/ideas appreciated.

Nigel

[Jack]

The plastic crank first appeared on serial number 48691. This is according to Contina documentation that I personally own.

Serial number 48691 was probably produced in the late 50's.

Documentation is very unclear as to when the plastic clearing lever first appeared, but I believe it was always installed by the time the Type I serial number reached 58000 or so.

Of course, many repairs performed on Curtas included substitution of the newer plastic parts in place of the original metal parts. If fact, Contina sent service bulletins to the service staff to describe such replacement procedures.

The plastic clearing lever is more robust than the metal clearing lever when it comes to "accidents" such as closing the cannister top on the ring portion of the lever.

The plastic crank was a design change that in part was implemented to reduce the number of stuck taper pins (used to attach the crank to the main shaft). Also, Contina felt that replacing the ridged aluminum crank with a more flexible plastic crank would reduce the number of bent main shafts should the instrument be dropped.

I believe that the use of plastic parts was frowned upon by Curt Herzstark. This probably applied to the use of a plastic cannister, too.
_________________
Jack Christensen
Timewise
32 Old Barn Road
Hawthorn Woods, ILLINOIS 60047
USA
847-550-5052 (evenings)
curta.info@gmail.com

[Nigel Fraser Ker]

Hi Jack,

Thanks very much for this information. Very interesting.

Kind regards,
Nigel