First, as a new member, Hello to all, it's good to know I am not the only one obsessed with this remarkable work of engineering.

I have a type II that's in really great shape, except ..... (I am sure you hear this allot), except one item, the red ring seems to be flaking off, in fact it appears to be chalk like, if touched that part falls off, sort of like plastic or enamel that has been exposed to prolong heat.

Have a 2nd vary old type II that has no red ring, its silver so I can not compare what it should look like, but I have a few type I's, and the red ring looks to be painted on, is this how the red ring is on the type II, or is it a plastic part?

Follow up, should my older type II, late 1954 have a red ring?

ErstO

Old style black body Type II Curtas do not have a red subtraction indicator band on the crank. The silver band was used to the indicate the crank was lifted.

The newer plastic cranks do have a painted red band that very often flakes off. Some good red enamel paint can be applied to replace missing paint. But the crank really should be removed first, and all the original paint should be removed. I use red automotive touch up paint from VW or Audi. Their Tornado Red matches the original red color used by Contina.

There were also metal cranks which had a red paint subtraction band (actually it was more of a fluorescent reddish orange color). This thicker paint also flakes off or dissolves when exposed to water or oil.

There seems to be little one can do to prevent the flaking...and once it starts, the paint invariably flakes off completely.

Thats good news, I can handle removing the crank and repainting the red ring, thanks for the tip

ErstO out

Hello, and sorry to reopen a quite old subject (but for a quite old calculator, truth don't change very often...)

Jack wrote:

I use red automotive touch up paint from VW or Audi. Their Tornado Red matches the original red color used by Contina.

Is the matching of color exact, or a good approximation ?

I know my monitor is uncalibrated, but I find it quite dark : http://encycolorpedia.com/841210 .

My own Curta II is begining to show signs of flaking of of the paint, and I'm considering two options :
1) trying to avoid manipulation and more flake of.
2) whole removal of the present paint, and repaint.
Of course, after a certain time with option 1, I will arrive at option 2
If I'm sure the color is indistinguishable from the original, I'll go to option 2 early.

Another note : apparently, VW/Audi stopped production of cars in Tornado Red in 2010/2011. Even if we still can easily find touch up paint pens now, there will be a time when an alternative reference will be needed.