Curta calculators

I have recently been in touch with a fellow by the name of Jack
Christensen, who is the preeminent repair person for the Curta
calculator in the US. He describes his activity as a hobby that
has gone out of control... sound familiar? He may be singularly
responsible for keeping these wonderful machines alive.
The Curta calculator looks like a pepper grinder, and is a marvel of
mechanical engineering and design. It was last manufactured in the
late 60's, and was sold commercially as late as 1972 when electronic
calculators finally killed their sales. Vintage car rally
participants use them, as they are allowed by their rules.
I have taken a fancy to these devices, and have offered to help Jack
re-create some of the critical parts that have been breaking, and are
unavailable for repair.
We are going to be making these critical parts to look as close to
the original as possible, but to be much stronger using modern
materials and methods. The replacement parts will be designed in 3D
in SolidWorks and stress analysis will be done using a package called
COSMOS. I would be happy to share the details.
Do you know anyone that may have a Curta, working or broken, that they
are willing to part with?
Please spread the word and let me know.
I can be reached at
Thank you,
Pelham, NH
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Wholy cow! these things are expen$ive on ebay! They must be a real collectible. There's one on now for $2300
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There was a lively discussion about Curta calculators on this group just 2-3 weeks ago. Several of us own them. I doubt that any of us would be willing to part with them as they start at about $700 on ebay.
Reply to
Jim Stewart
Doesn't the first statement lead one to believe that you have some (at least one) of your own, in which case the second statement does not make sense.
Unless of course you just don't want to take one of your own Curtas apart and want someone else's to figure out how to make the parts you want to repair.
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No, I don't own one of my own.
I would prefer to find some broken ones.
I would buy them, I do not want to work on someone's working unit; in fact, I don't want to work on them at all... Jack is the expert and his hands will do the work.
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Huh. I hadn't thought of those for a long time, but I still have a copy of "Sky and Telescope" with an ad for one of them. A beautiful little gadget. On the facing page was an ad for one of the very first four-function electronic calculators. The ad for the mechanical calculator never appeared again in S&T, that I can recall. Maybe I'll see whether I can dig it out...
Sorry can't help you there. The only one I know of is in a museum. I don't think they're interested in selling.
Al Moore
Reply to
Alan Moore
A aside: there's an article on the Curta in the January 2004 Scientific American.
I'd love to have one, but not at the current prices.
Reply to
Dave Martindale
It all depends on matching buyer and seller. I actually collect slide rules, and I have *never* found a slide rule at a flea market or a garage sale or an estate sale. But I don't visit them in any organized fashion; just stop at them from time to time. I would have bought the collection of 26 for $10, even if it duplicated many of my existing rules. But I wasn't there.
Almost everything I have was found on ebay. There are 500-600 slide rules listed per week on ebay, and most of them sell, so it *is* possible to sell them, not give them away. Pickett rules tend to sell for $10-30 each, depending on condition and what's included. I'm sure a collection of 26 different models in decent condition would have sold for a couple hundred dollars to the right buyer.
Yes, there are dealers who sell them for high prices. But the dealers' prices are 3-4 times ebay prices. In many cases, the dealers buy their stock from ebay in the first place. The difference is that a dealer will buy a bunch of rules from ebay, clean and adjust them, discard the fraction that aren't in good condition, photograph the rest and build a web page to show them, then sell them with a money back guarantee. They have to pay for their own time and overhead and make a profit.
If you want to buy a single rule that's guaranteed to be in good condition, or you're wealthy enough, buying through dealers makes sense. If you just want a wide variety of rules, are willing to have a few of your purchases turn out to be duds, don't mind doing your own cleaning and adjusting, and are more interested in "functioning" than "museum display quality", you can pay a factor of 3 or 4 less buying directly from ebay.
Reply to
Dave Martindale
I found a 6 ft long Pickett slide rule at a garage sale a couple years ago. Yes 6 feet. One of those used in classrooms for demonstration. Paid 10 bucks for it. Unfortunately it was destroyed when my house burned. It was pretty cool. The slide rule... not the fire
Reply to
dann mann
Those are the only place Ive found them. And thrift stores.
"Gun Control, the theory that a 110lb grandmother should fist fight a 250lb 19yr old criminal"
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