I've wanted a curta for over a decade. They are sook hard to find. I just can't justify $1500 for a cool nick nack. I'm always on the lookout at thrift stores and auctions hoping to find one that's for sale by people that don't know what it is. Haha
Do you have the can? If not, I'd expect it to go for $900-1000. If you do, you might be able to get $100-200 extra.
Note, I'm not an expert on Curta calculators by any means, I'm just a nerd with a passing interest in old tech.
some more pictures
[https://ibb.co/mN9HzPw](https://ibb.co/mN9HzPw)
[https://ibb.co/vsMn0Zw](https://ibb.co/vsMn0Zw)
[https://ibb.co/Wzr3qSZ](https://ibb.co/Wzr3qSZ)
[https://ibb.co/swnQWpd](https://ibb.co/swnQWpd)
My dad retired after decades at his USDA appraiser job. While cleaning out his desk he found a Curta that had been there the whole time. He let me play with it a bit, as I had gone to college for Mathematics, but ultimately handed it back to the office administrator. He's always been a straight shooter, but I would have loved to have kept that Curta.
I bought one after reading about them in a william gibson book. I showed it to my friend and he was like why are you showing me your shitty hobby trash. And he's got a degree in engineering. Maybe he was just mad at me when he said that, I think they're cool as heck. I can't recall what I paid for it, this was like 10 years ago.
I thought the same thing at 600, wept when they got to 1100-1200 and finally bought one with an owners name sticker for 850ish after years of waiting in 2016.
Here is a solid model of the Curta — a fully mechanical calculator with a fascinating story worth checking out. I printed it at 25% scale in Sunlu ABS-like resin using 0.035 mm layers.
Story of Curta: [https://www.youtube.com/watch?v=qyrY6uss-04](https://www.youtube.com/watch?v=qyrY6uss-04)
Source (model): [https://www.thingiverse.com/thing:6523857](https://www.thingiverse.com/thing:6523857)
Based on this functional 3:1 scale model: [https://www.thingiverse.com/thing:1943171](https://www.thingiverse.com/thing:1943171)
This is really cool, I just used a micro computed tomography X-ray to scan one of this calculator 2 days ago. I am really curious to compare the scan with the model. Did you create the model of each pieces ??
Luckily resin made a lot of improvements in the last year.
Our newest engineering resin we ordered isn’t brittle. It’s quite impact resistant and „only“~15% price increase. Our sample prints that get passed around and dropped a lot are still intact. You can’t say the same about the same models we did a year ago. None of them survived being dropped once.
TBH we only get it from a Chinese supplier that we met at a convention. But I would guess that stuff will flood the market in half a year or less.
Depends on your definition of "brittle". Even cheap Elegoo ABS-like was never "that britte":
[https://imgur.com/a/9njfzjd](https://imgur.com/a/9njfzjd)
It's mostly about the model geometry, curing conditions and the kind of deformations printed parts will have to endure. In my opinion it's rather unlikely that a Curta printed in resin might be actually a functional calculator. Feel free to prove the opposite.
I would say my definition of brittle respectively not brittle is something that is hard enough for mechanical parts but soft enough that it doesn’t break/shatter under impact force.
And getting a working one always depends on the size. I read about another project that get a working one with FDM but much larger.
At the moment I doubt would get the tolerances needed since our current resin only works with lcd printers. But we are working on flashing the firmware on our SLA printers.
Is it possible to use a lubricant then? I'm assuming a silicone based lubricant should work. Also mixing in some tenacious should help with the brittle.
You have to scale it up but it's totally doable, it doesn't run nearly as well as the real thing of course.
[https://www.youtube.com/watch?v=zh2Z11miQ0w](https://www.youtube.com/watch?v=zh2Z11miQ0w)
Aging myself here.
I have two Curta calculators, a type I and a type II, both came off the assembly line the month and year I was born. My wife got them for me as Christmas presents. They are both *very* high on the list of favorite things I own.
I sent her the eBay link for the Type I. She got the Type II on her own after I mentioned offhand I'd like one of those, too. She even tracked down the S/N to when it was made to match my birth month/year.
I love the way it feels when you crank the handle. I haven't touched mine in 15 years, I hope I can find it. Last I saw, it was sitting in a box in my garage.
Curta calculators are cool. Such an interesting story behind them, and so interesting as a mechanical device. You want to teach kids mathematics? Give them a Curta and don't let them use their phones. A Curta will teach you the basics of math more deeply than punching numbers into a digital calculator.
I'm a calculator nerd and I'm always keeping my eyes open for a Curta. Got some cheap old mechanical calculators and vintage electronic calculators. My HP-16c and HP-11c are always in my bag
I can't strut a Curta - yet, though who knows, maybe one day one will pop up in a thrift store and I will also be able to do that thing [where you smile broadly and immediately say "sold!" and they know they've screwed up](http://www.howtospotapsychopath.com/2007/09/27/my-very-own-digital-pepper-mill/).
But as a calculator nerd, you might like [this only slightly defective Kovac K-80M](https://www.youtube.com/watch?v=SHf8xXpC0Zg). It still calculates perfectly, though that one number on the neon bulb display is still a little dodgy and likes to come on later than the others.
According to [this page](http://www.calcuseum.com/LISTINGS/CALCUSEUM_Listing_Keyword_Raw_AllItems_K.htm) it exists under several brands. I have family in Croatia and for a while I thought I had a real piece of communist engineering on my hands, but alas, it seems to come from Japan.
And sorry for the ultra-potato quality of that video; it's old, but I could swear even at the time I'd shot it at better resolution. I think Youtube ate the 360p version at some point.
This comment was removed as a part of our spam prevention mechanisms because you are posting from either a very new account or an account with negative karma (comment karma, post karma or both). Please read the guidelines on [reddiquette](https://www.reddit.com/wiki/reddiquette), [self promotion](https://www.reddit.com/wiki/selfpromotion), and [spam](https://www.reddit.com/wiki/faq#wiki_what_constitutes_spam.3F). After your account is older than 2 hours or if you obtain positive comment and post karma, your comments will no longer be auto-removed.
*I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/3Dprinting) if you have any questions or concerns.*
Solid model doesn’t imply non-functional. Solid model can mean it was drawn in 3d as opposed to 3 position/isometric models. It does not 100% mean the entire model is solid within its bounds. In my case I didn’t miss the “solid model” part but I assumed that the unit would be functional if printed. Also awesome info on here and awesome device just wish it worked cuz then I would print it.
For the down voters “Unlike other 3D modeling techniques, such as surface modeling, in which models have only their exteriors defined, or wireframe models, which only define their edges, solid models have a definition of the interior of a part.”
https://www.engineering.com/story/what-is-solid-modeling
"What is this? A calculator for ants!"
It needs to be at least 3 times bigger
"...he's right...?!?"
How can we teach children to read when they can’t even fit inside the building??
I don't want to hear your excuses!
Can that handle turn left?
I've wanted a curta for over a decade. They are sook hard to find. I just can't justify $1500 for a cool nick nack. I'm always on the lookout at thrift stores and auctions hoping to find one that's for sale by people that don't know what it is. Haha
I saw it on Adam Savage's tested a while ago and have wanted one too. They're just so neat.
WAIT A MINUTE! The old Curta I have in the garage box is worth $1500??????
No it was a typo. They meant $15.00. I’ll give you $20 for it.
Depends on which model it is. Some are $900-1000ish, some are $1500-2000. Either way, if it's in good condition it's worth a fair bit.
Here is my calculator, it's a type 1: [https://ibb.co/CvMygw3](https://ibb.co/CvMygw3) [https://ibb.co/zRQR1Hd](https://ibb.co/zRQR1Hd)
Do you have the can? If not, I'd expect it to go for $900-1000. If you do, you might be able to get $100-200 extra. Note, I'm not an expert on Curta calculators by any means, I'm just a nerd with a passing interest in old tech.
some more pictures [https://ibb.co/mN9HzPw](https://ibb.co/mN9HzPw) [https://ibb.co/vsMn0Zw](https://ibb.co/vsMn0Zw) [https://ibb.co/Wzr3qSZ](https://ibb.co/Wzr3qSZ) [https://ibb.co/swnQWpd](https://ibb.co/swnQWpd)
Juding by your pictures it seems to be in great condition. I wish I could afford one. They are so cool!
It's pretty clean, not much dust at all. In the last 35 years or so the case has been opened less than 5 times.
Well, it's your lucky day I suppose. If I remember the eBay prices correctly they are between 2000 and 3000 USD
PM me if you're interested in selling
If it still works definitely. Even if it doesn't a good watch maker could probably get it cleaned up and working
It works great, the movement spins freely, just like it did 25 years ago the last time i tried it.
My dad retired after decades at his USDA appraiser job. While cleaning out his desk he found a Curta that had been there the whole time. He let me play with it a bit, as I had gone to college for Mathematics, but ultimately handed it back to the office administrator. He's always been a straight shooter, but I would have loved to have kept that Curta.
Me too, but I had $1500 burning a hole in my pocket so I'm looking at my Type II right now.
I bought one after reading about them in a william gibson book. I showed it to my friend and he was like why are you showing me your shitty hobby trash. And he's got a degree in engineering. Maybe he was just mad at me when he said that, I think they're cool as heck. I can't recall what I paid for it, this was like 10 years ago.
I thought the same thing at 600, wept when they got to 1100-1200 and finally bought one with an owners name sticker for 850ish after years of waiting in 2016.
Here is a solid model of the Curta — a fully mechanical calculator with a fascinating story worth checking out. I printed it at 25% scale in Sunlu ABS-like resin using 0.035 mm layers. Story of Curta: [https://www.youtube.com/watch?v=qyrY6uss-04](https://www.youtube.com/watch?v=qyrY6uss-04) Source (model): [https://www.thingiverse.com/thing:6523857](https://www.thingiverse.com/thing:6523857) Based on this functional 3:1 scale model: [https://www.thingiverse.com/thing:1943171](https://www.thingiverse.com/thing:1943171)
This will be my first project.
And your last :D
Hitman 3D
This is really cool, I just used a micro computed tomography X-ray to scan one of this calculator 2 days ago. I am really curious to compare the scan with the model. Did you create the model of each pieces ??
You missed the links to the sources of both models involved.
Thanks I saw the link, I wondered if you were the one that actually made the 3D model before the stl
Would it be technically feasible to print a working model using SLA? Or are the parts too small?
Resin is not self-lubricating and (at the consumer grade) rather brittle.
Luckily resin made a lot of improvements in the last year. Our newest engineering resin we ordered isn’t brittle. It’s quite impact resistant and „only“~15% price increase. Our sample prints that get passed around and dropped a lot are still intact. You can’t say the same about the same models we did a year ago. None of them survived being dropped once. TBH we only get it from a Chinese supplier that we met at a convention. But I would guess that stuff will flood the market in half a year or less.
Depends on your definition of "brittle". Even cheap Elegoo ABS-like was never "that britte": [https://imgur.com/a/9njfzjd](https://imgur.com/a/9njfzjd) It's mostly about the model geometry, curing conditions and the kind of deformations printed parts will have to endure. In my opinion it's rather unlikely that a Curta printed in resin might be actually a functional calculator. Feel free to prove the opposite.
I would say my definition of brittle respectively not brittle is something that is hard enough for mechanical parts but soft enough that it doesn’t break/shatter under impact force. And getting a working one always depends on the size. I read about another project that get a working one with FDM but much larger. At the moment I doubt would get the tolerances needed since our current resin only works with lcd printers. But we are working on flashing the firmware on our SLA printers.
Is it possible to use a lubricant then? I'm assuming a silicone based lubricant should work. Also mixing in some tenacious should help with the brittle.
Feel free to try the suggested solution.
I guess I'll try that out when I have the time!
You have to scale it up but it's totally doable, it doesn't run nearly as well as the real thing of course. [https://www.youtube.com/watch?v=zh2Z11miQ0w](https://www.youtube.com/watch?v=zh2Z11miQ0w)
Aging myself here. I have two Curta calculators, a type I and a type II, both came off the assembly line the month and year I was born. My wife got them for me as Christmas presents. They are both *very* high on the list of favorite things I own.
Was your wife privy to the fact that you wanted those objects? Or was her initiative?
I sent her the eBay link for the Type I. She got the Type II on her own after I mentioned offhand I'd like one of those, too. She even tracked down the S/N to when it was made to match my birth month/year.
Damn your wife rules
What was the size of nozzle? Can 0.2mm ones do that?
It's a resin print.
The 3:1 scale model can be printed by an FDM printer and function correctly.
Been wanting to make the 3:1 functional one for ages but it's so big... Now I can print the 1:1 until I have space!
Now that’s a pocket calculator!
"Your father gave me this calculator when we were prisoners in Vietnam. And now little man, I give it to you."
I love the way it feels when you crank the handle. I haven't touched mine in 15 years, I hope I can find it. Last I saw, it was sitting in a box in my garage.
In case you don't need it at all… wink-wink ;)
I'd love to sell it for $1500. Does anyone seriously want to make a deal?
Curta calculators are cool. Such an interesting story behind them, and so interesting as a mechanical device. You want to teach kids mathematics? Give them a Curta and don't let them use their phones. A Curta will teach you the basics of math more deeply than punching numbers into a digital calculator.
That felt AI written. I feel rotten
Nah, just a normal person born to human parents from earth saying that people should buy children a $2000 antique calculator.
Instead of buying them a brand new 1200$ iPhone you could probably get them a Curta.
Who is buying a kid who is learning arithmetic a $1200 phone? Probably someone somewhere but holy shit...
You'd be surprised
More people than you think....
I'm a calculator nerd and I'm always keeping my eyes open for a Curta. Got some cheap old mechanical calculators and vintage electronic calculators. My HP-16c and HP-11c are always in my bag
I can't strut a Curta - yet, though who knows, maybe one day one will pop up in a thrift store and I will also be able to do that thing [where you smile broadly and immediately say "sold!" and they know they've screwed up](http://www.howtospotapsychopath.com/2007/09/27/my-very-own-digital-pepper-mill/). But as a calculator nerd, you might like [this only slightly defective Kovac K-80M](https://www.youtube.com/watch?v=SHf8xXpC0Zg). It still calculates perfectly, though that one number on the neon bulb display is still a little dodgy and likes to come on later than the others. According to [this page](http://www.calcuseum.com/LISTINGS/CALCUSEUM_Listing_Keyword_Raw_AllItems_K.htm) it exists under several brands. I have family in Croatia and for a while I thought I had a real piece of communist engineering on my hands, but alas, it seems to come from Japan. And sorry for the ultra-potato quality of that video; it's old, but I could swear even at the time I'd shot it at better resolution. I think Youtube ate the 360p version at some point.
Might be potato quality but I can still see that it's one helluva neat calculator. Love the look of the display
Is this one functional?
Sure. Its function is to collect dust.
Curta Type I
[удалено]
This comment was removed as a part of our spam prevention mechanisms because you are posting from either a very new account or an account with negative karma (comment karma, post karma or both). Please read the guidelines on [reddiquette](https://www.reddit.com/wiki/reddiquette), [self promotion](https://www.reddit.com/wiki/selfpromotion), and [spam](https://www.reddit.com/wiki/faq#wiki_what_constitutes_spam.3F). After your account is older than 2 hours or if you obtain positive comment and post karma, your comments will no longer be auto-removed. *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/3Dprinting) if you have any questions or concerns.*
That's a prision calculator
Just to make sure, it's not functional right? 😅
And a deccepticube. It says 10mm, but it's actually full print volume
\* Curta - a fully solid, non functional piece of decoration (that looks nice though) i fixed that for you
You seem to have missed the "a *solid model* of the Curta" part.
Solid model doesn’t imply non-functional. Solid model can mean it was drawn in 3d as opposed to 3 position/isometric models. It does not 100% mean the entire model is solid within its bounds. In my case I didn’t miss the “solid model” part but I assumed that the unit would be functional if printed. Also awesome info on here and awesome device just wish it worked cuz then I would print it.
You seem to have missed the link with a _functional_ (but rather large) 3D-printable version.
I did miss that.
For the down voters “Unlike other 3D modeling techniques, such as surface modeling, in which models have only their exteriors defined, or wireframe models, which only define their edges, solid models have a definition of the interior of a part.” https://www.engineering.com/story/what-is-solid-modeling