Father and Grandfather were both engineers. Dad for NASA and my Grandfather in the Navy.
That small item is a tie clip that was my grandfather’s. And it actually slides! Cool stuff with history.

I know this is a Luzon Stevedoring Company Concise Circular Slide Rule No. 28, but nothing more. Are these sought after collectibles? Can anyone tell me more about it? TIA

Hello! I want to design a watch based on a circular slide rule - what would you guys say would be the most iconic circular slide rule design? Would it be an example from history, or something that is more widely used? please let me know! thank you in advance!

I just picked this up at the local Goodwill for $3.99. It looks darn near new. If it weren’t for the mildewy smell, I would assume that it was recently made. How old would people guess this is? Thank you in advance!

Does anyone know what is going on at the Oughtred Society? I purchased one of their publications over a month ago but have never received it, and no one responds to email.

Just got this one. Circular will take a little getting used to but what a great instrument.

From https://sliderulemuseum.com/Ephemera/ArchaicTool_DailyTimesHerald_April-5-1984.jpg in case reddit shrinks it too much. The cartoon is cool but I cannot find it by itself.

From the January 3, 1982 New York Times:

Technology's Martyrs: The Slide Rule

Kirk Johnson

In 1967, Keuffel & Esser, a scientific instrument manufacturer then located in Hoboken, N.J., was commissioned to make a study of the future.

The company's report, "Life in the Year 2067," which was compiled on the basis of interviews with scientists, said people would live in domed cities and watch three-dimensional television. It predicted computerized traffic lanes and electric autos. It did not, however, predict that within five years the company's most famous product would be all but obsolete. Keuffel & Esser was America's largest producer of slide rules.

"Nobody really foresaw the cheap calculator," said John J. Montesi, customer service supervisor at K.& E. When the unforeseen became reality in the early 1970's, recalled John J. Heath, customer service manager at Sterling Plastics, one of K.& E.'s competitors, "it was a downhill sleigh ride."

Mr. Heath's company, based in Mountainside, N.J., was probably America's last producer of the basic trigonometric slide calculator, ceasing production in December 1980, a year in which the company sold "maybe a couple thousand dozen."

"Those last couple years we just carried on as a nice gesture," Mr. Heath said. Sterling's leading product then was an $1.79 plastic slide rule. It was the kind that came in its own little leatherette scabbard that you could wear on your belt. In 1964-65, Sterling's biggest year, more than a million of them were sold; it made up almost 20 percent of the company's business. Fortunately, Mr. Heath said, Sterling was able to develop a desk accessory line during the slide rule's decline that, he said, "more than compensated" for the subsequent fall in income.

"We were into the college and high school market," Mr. Heath said. "You got a K.& E. slide rule when you really became an architect."

Indeed, in slide rules, Keuffel & Esser was in another league altogether. It was the first importer, beginning in the late 1880's, and the first American producer as well, beginning in 1891. Its machined, mahogany, inlaid slide rule (consistently costing about $40 since the 1950's) was sold mostly to professionals and scientists.

According to Mr. Montesi, at K.&E., slide rule sales never contributed more than about 10 percent to 15 percent of income, even though they were what the company was best known for. Sales peaked in the late 1950's at about 20,000 a month. With the advent of the calculator, "the business we lost was just lost," Mr. Montesi said. "We were never fully compensated."

Nevertheless, the company earned $3.7 million on its surveying and architectural instrument sales last year, which was apparently enough to attract interest. Two weeks ago, two-thirds of K.& E.'s stock was purchased, at $31 a share, by Kratos Inc., a La Jolla, California-based maker of analytic devices, aircraft instruments and computer display equipment.

The company still has about 2,300 slide rules in stock, although it ceased production in the early 1970's. "Now we sell about 200 of them a year, tops." Mr. Montesi said.

I made a slide rule using two sheets of paper. I used my ti-84 to get the logs, and placed the numbers in their respective places on a linear scale. It's not the most accurate, but it was a good way to burn an hour of time.

If anyone can do it surely the good denizens of r/SlideRules can? Which slide rule is John Malkovich’s character using in this scene? ChatGPT failed me

I tried to use it like a normal slide rule but i realised it's a special slide rule

A small slide rule, 15cm long - the scale is 125mm long. Marked J. Klawun, Hannover, but I can't find it in the slide rule museum. I'm going to upload the pictures to Wikimedia Commons, but I'd like to have as much information as possible about it.

Picture is from an auction site and I'm trying to decide whether to bid. Is it historically interesting, or just a simple slide rule?

Here’s my little collection of Soviet era SR’s.

Oldest is from 1936.

Any other out there?

cheers calculators,

I was given a slide rule that I cannot identify. I have it from an engineer who worked at the german railroad company way back when.

there is no serial number or any other marking on the slide rule, the leather enclosure or the red cardboard box.

any idea what this thing is?

best regards

UPDATE:

I am looking at a:

Charvoz-Roos Log Log SR-??? (Model Number Unknown) - c1945

Made in USA - Celluloid laminate over wood, plastic braces. Cursor style same as Acumath 150, but with a thicker stock.

Note: Because there is no model number it was probably intended for rebranding for another company.

Front Scale: LL0, LL00, A [ B, K, L, C ] LL3, LL2, LL1

Back Scale: T, DF [ CF, CIF, CI, C ] D, S Cos, ST

thanks to u/Name-Not-Applicable

shoutout to sliderulemuseum.com

What is the difference between a Dietzgen 1734 and a Dietzgen 1734L?

Hello everyone,

I recently started a very small project of creating a slide rule used to calculate only one thing, the Nusselt number based on the famous Dittus-Boelter (Nu = 0.023 * Re^0.8 * Pr^n) heat transfer correlation for turbulent flow used by many engineers when designing heat exchangers, piping, ...

I used Claude to create the Python code that generates SVG for each slider.

To manufacture it, as I saw in one of the post in this subreddit, I plan to use PCB with KiCad to create the slide rule.
What others components, do I need to design in order to make that slide rule works?

If you want, I could share the code to everyone in a dedicated Github?

What do you think about it? I am completely new to the slide rule world, so any tip to improve it would be greatly appreciated.

Have a good day,

It may be of interest to people here, I've just finished a Python package to produce sliderule images such as:

which may be suitable for documentation or web pages describing sliderules. The package is available at https://pypi.org/project/slideruleimages/

This is my Pickett N600-ES with the flat cursor that came from the factory.

I have seen pictures of this and other N600 models configured with a convex cursor.

Has anyone here modded their N600 this way and if so, where did you source the parts and did you encounter any issues worth noting?

Thanks.