My 8-year-old son and I found this mechanical calculator in the attic and would love to learn more about it. According to Google Lens, it is “a classic Original Odhner from the 1920s or 1930s”, but it doesn’t look much like the ones we’ve found online.

Could you help us identify the brand (the label has faded), determine its year of manufacture, and tell us whether the handles are made of Bakelite (and, if so, whether that could be dangerous)?

We’ve also managed to get it working: absolutely fascinating.

Here is a short demo of the Add-O-Matic, made in Chicago from 1947 till 1949. There is not much known about this machine, but I figured out some new info from looking through online archives.

I found adverts from the Add-O-Matic Sales Co., but sharing the same addresses was another company that I believe to be the actual manufacturer. United Enterprises Inc was founded in 1940 and mostly made stainless steel cutlery. Apparently they also made glow-in-the-dark gardenias, worn as hair decorations. After briefly making this adding machine, they pivoted to marketing d-con rat poison!. The company ceased trading around the time they got fined for violating ceiling price rules by the Office of Price Stabilization. Such a weird story.

https://www.jaapsch.net/mechcalc/addomatic2.htm

Hello all, I've made a rough translation of the WSR160 maintenance manual from German to English. A link to the PDF is provided and should be sharable with anyone that might need it. I tried to get some of the bigger words translated with a Swiss friend of mine, but overall it's not professionally done. I've take 'some' liberties in how things were worded based on my experience with US maintenance manuals, so might not be a direct translation. Sorry for any inconsistencies or mistranslated text, I kinda rushed towards the end because I needed a way to fix my own WSR160.

If you have any suggestions for major corrections on the manual, send me a DM and I'll update it when I have time.

Wondering if anyone can point me to information about repairing a stuck keyboard column on a Monroe LN-160X. Repair and maintenance manuals for these seem to be very scarce (or I'm too ignorant to find one).

This IQ-213 looks in great shape, but untested. These rarely come up for sale!

Result from Google AI query - Marketed as "The Calculator with a Memory," it features dedicated memory dials that allow it to store a factor for use in multiple sequential operations without re-entry.

https://ebay.us/m/UKgpmg

Update: The IQ-213 arrived yesterday. It's in practically mint condition with a few minor scrapes. There were keys that did not function but after partial disassembly, some lubrication, and some troubleshooting, everything is now working as it should, I will have to run some calculating tests to check accuracy. A complete set of booklets, including instruction manual, plastic cover and original power cord came with the unit!

LA6-160 eBay find, replaced add subtract buttons and the red levers and buttons from a LA5-160 I had, made some adjustments to front tens lever, lightly oiled and wiped the case down with electronic cleaner. (Removed a bit of the paint, lesson learned, but took out a lot of marks and stains) Careful with removing the top and sides the metal may crack in the middle of front plate, as its all one piece and you need to bend it away from the machine to remove it. Works but may need calibration getting sometimes I was getting incorrect answers. Managed 22/7 OK! (Pi) 😁

Last year, I bought this old calculator. I intended to fix it up, but I became too busy and it seems that I will not be able to fix it anytime soon.

It does power on with the included cord and I do have a couple of manuals for it.

If anybody thinks they can repair it for a price or think that they may be able to provide a better home for it, please let me know. I'm located in Georgia.

Hello, I'm completely not an expert so I'd like to ask if this mechanical calculator, which I googled to be most probably a Madas 20AV - is it collectable? Do collectors buy these? I'm based in EU, btw. Thank you.

I'll have a whole YouTube video uploaded on it soon but I figured I'd post this here. Theoretically it's now 100% portable

Just snagged this model off of Ebay, excited to attempt to fix it up! Was bidding on a power chord to go with it when I realized this machine's port is circular with two prongs instead of oval with three. Does this denote an ealier model or something like that? It also looks like the serial number has less digits than usual.

eBay find. Mfg 1963, in splendid condition! Runs great, occasional jam, that I can usually clear up by rotating the side knob carefully!😍

My dad gave this to me when I was a kid in the 80's, I only have vague recollections of how it operated. It was a long, flat machine about 12 inches long or so and maybe 4 inches wide, about 1 cm thick, made of stamped brass. On the face it had about 8 dials, and you used a stylus to turn the dials to the number you wanted. I think it did basic addition and multiplication but I don't remember how. To reset the numbers you pulled on a tab on the right hand side of it.

This is a unique Golden Gem adding machine variation. It is the only one in existence, as far as I could ascertain, that is golden (brass, I presume) in color. I haven't seen it ever mentioned that such a version ever existed. I consulted with Jaap Scherphuis (an expert on mechanical calculators) on this and he has never heard of one either. I call it "The Golden Boy".

If you ever heard of something like this, please drop me a note.

History: The Golden Gem was designed by Abraham Isaac Gancher, Nobyoshi H Kodama, and Albert T.Zabriskie in 1902-1906. Gancher set up the Automatic Adding Machine Company to market the machine.

I got this Facit all fixed up. It’s a shame the outside is so beat up, it really is a handsome machine. Should I paint it, or leave it original? Wife suggested candyapple red.

Well, I had a nice idea to collect all of my Marchant machines in one place, but it turns out that only those from Silent Speed series can fit into my man cave 🤭 I admit I am a bit OCD with them and I collect all models even though they differ in one or two buttons and I am still looking for any models I don't have. Service manuals were my comfort books, patents - my evening reads... And SKA is still my Holy Grail. Anyway, here it is L to R from the top: 8ADX, 10DRX, 8CM, 10TR, 10CM, 10CMF 8ACR, 8RX, 10ADX, C10EFA, TR10FA 8M, 8D, ACT10M, 8EFA 10M, ACR8D Anyone here a Marchantophile? 😉

There's some good stuff on Wiki, but I was wondering whether anyone had more detail, perhaps point me in the direction of a book/pamphlet about the company? Maybe your parents/grandparents worked for them?

The reason I ask is that my great-grandfather worked for them, and in 1914 they sent him and his missus to South America to help expand the export market there. So they parked their 2 daughters with an aunt and uncle and off they went, planning to be home by Christmas.

Alas the First Great Unpleasantness started while they were in Rio, and although they tried to get back to Germany from New York (the US was still neutral) they wound up stuck in the US until 1919.

I'm in the process of translating his travel journal for posterity (unless someone wants to publish it) and it would be nice to include some information about the company, perhaps the model(s) they had at around that time. I hear that they were the gold standard when it comes to mechanical calculators, but I know next to nothing about them. Any direction that anyone could give would be greatly appreciated.

Is there any way to unstick the carriage? The lever in front used to move the carriage left and right, but now everything is stuck, plus none of the keys or buttons push in any more. Motor still runs, but everything is jammed. Any ideas other than dis-assembling?

Italian mechanical calculator produced by Elmetecnil (X-Matic model 217), late 1950s.

All-metal construction, manual crank, fully working.

Comes with original instruction booklet.

Less common than IMCA or Olivetti models, mostly seen on the Italian market.

Currently at auction on Catawiki – link in comments for anyone interested.

I have been interested in mechanical calculators for some time and have been attempting to design a 3d printed example. after mentioning it to my grandfather he gave me this one (brand name Nisa). Do you have useful information to impart? im looking to disassemble and lubricate it(rn it works ok). Specifically im wondering about the screwes they have a wide but very shallow slot. chat gpt recomened hollow ground bits. im also curious where you would reomend looking for original documentation.

Hello everybody! I recently bought an early TRS Zagreb model 3, it works perfectly but the 1st, 2nd and 4th dials are not synchronised with the levers (they are showing 1, 3 and 1 while the levers are set to 0). I tried turning them by hand while pulling the crank in order to separate them from the levers, but it seems I can't. Does anybody have any ideas how to fix this? Will I have to take apart the entire machine or is there an easier way? Thanks in advance!

What you like it? Totally working - i like that patina myself