rules have come in different formats over the years. The most familiar is probably the 3-part
model with a fixed outer frame and a sliding inner rod, and a sliding clear window with a reticle line
etched into it for aligning numbers (the cursor). While far from being
any type of "collection," I do have a couple nicely preserved models. The ones from Keufel & Esser
(K&E) are at the top of the table
below. The Beginner's slide rule model is very basic with graduations on one side and some conversions
on the other. The best of all is the Pickett N600-ES Log-Log
that is in new condition and actually still has the box, leather case, instructions and certificate.
The Pickett N600-ES is the slide rule model that went to the moon* with the Apollo astronauts
(not the one I own, of course).
Finally, a few of
the cardboard calculators I have are at the bottom. Probably only the VSWR Calculator from M/A-COM can
be considered collectible. My good friend Patrick Fitzgerald bestowed it upon me when I went to work
for him at General Electric right out of college. I can recall some of the older engineers still using
slide rules there when I arrived in the 1980s. In fact, the first algebra textbook I had in a community
college right out of high school in 1976 had a section in it on how to use a slide rule. The
Sterling 684 plastic slide rule that I bought at the bookstore
is show below. Shortly thereafter, the HP-35 hit the market and the world changed forever (now that
was truly a disruptive technology).
April 2016 Update: *According to the Smithsonian National Air & Space Museum,
the N600-ES did not actually make it to the moon because it was aboard
Apollo 13, which experienced a system failure that required the crew to do a U-turn
and execute manual maneuvers to get home safely.
June 2015 Update: Thanks to generous RF Cafe visitors who either sent me hard copies
or high-res photos of their Cardboard Slide
Rule Calculators (which I have dubbed The Original Mobile Apps™), the number has grown so large
that they required their own page.
◊ Here is my collection of vintage
Cardboard Slide Rule Calculators.
Here is the definitive source: International
Slide Rule Museum
- Slide Rule
Library Archive of books,
manuals, instructions and ephemera.
Instructions on how to use
a slide rule.
◊ Or, try the Slide Rule
◊ See the The Quick and Easy "Lawrence" Slide Rule Instruction Book
The Slide Rule Universe -
◊ Visit the Oughtred Society
(William Oughtred - inventor of the slide rule in 1622)
new-in-the-box, mint condition
◊ Virtual Slide Rules:
rule - EngCom.net,
rule - Antiquark.com
◊ Here is a website on
(slide rules and other instruments of math, drafting, science, and music)
Pickett N600-ES Log-Log Slide Rule (ES
stood for the 'eye saver' yellow color)
(this is the model that was
aboard the Apollo 13 mission and according to
Buzz Aldrin, the one he took to the moon aboard Apollo 11). According to information
from Pickett, my N600-ES was manufactured sometime between March and June 1959. See "The Great Pickett
Slide Rule Apollo Conundrum."
K&E Model N4080-3 Log Log Duplex Trig, S/N 467192, Copyright 1947 Slide Rule
(wooden frame & bar w/metal ends)
K&E Model 4081-3 Slide Rule, S/N 087105
(wooden frame & bar w/metal
Sterling 684 White Plastic Slide Rule
(I bought this for my first algebra
class in 1976)
Skala Wilcza 32 Wooden Slide Rule (Poland)
Thanks to Alan Kealey for the donation!
Pickett N1010-T Slide Rule
(found in my father-in-law's basement)
Cleveland Institute of Electronics 515-T Slide Rule (made by Pickett)
to Mr. Joe Hernandez (KN2A), the complete set of four
Cleveland Institute 515-T manuals is
now available here.
This advertisement appeared in the August 1967 edition of Electronics World magazine.
The unique slide rule, leather case, and 4-course instruction booklet was "...deliberately underpriced
at less than $25."/p>
K&E Beginner's Slide Rule, Model 4058C
(all-wood frame & bar)
Lawrence Slide Rule Instruction Book
Cleveland Institute of Electronics Slide Rule Product Feature
January 1965 Popular
Gong Se He Ying
Metalworking calculator for Iron materials
Slide Rule Wallpaper
Click on the image to open it in a new window, then
right-click on it and choose Set as Background
Texas Magnum, World's Longest Slide Rule
(352 feet long, 300 pounds)
Soviet Slide Rule Watch
Projection Slide Rule