Slide Rules. Collecting and discussing.
Slide Rules. Collecting and discussing.
(OP)
Hello all,
You are invited to share views and thoughts about slide rules. I have been collecting these devices on a rather small scale and had fifteen of them when my collection took a quantum jump. I was visiting the local book store to buy a book on flowers (yes, flowers) when I happened to ask the store-keeper if he perhaps had any slide rules. He gave me a puzzled look and then said "Yes, I found a box with some forty old slide rules yesterday. I haven't decided what to do with them yet".
Need I say that I saved them from the scrapheap? I got a substantial addition to my collection at a price that we both were very pleased with. He because he got anything at all and I because I paid about a tenth of what I had expected to pay.
I have mostly European and Japanese slide rules. Faber-Castell, Aristo, Sun-Hemmi and some less known makes like Graphoplex (French), Diwa (Danish), Royal Slide Rule (British) and Eco Bra (can't make out from where it comes).
There is a certain standardisation among slide rules. There are the scale systems; Mannheim, Rietz, Darmstadt, Electro, Disponent and some other special systems. There is one that intrigues me. It is called Tachymeter and seems to have been used by surveyors. And there are probably many more that I haven't discovered yet.
The slide rules from the BHP era look very much the same except for the introduction of the Duplex slide rules in the late fifties/early sixties. That was also when some colour was added - except for the "reversed" scales (increasing from right to left instead of from left to right) which seems to have been coloured red for a very long time.
It was only AHP that design people started to make the slide rules more and more attractive. Mild colour coding, more scales and cursor lines, extra functions, friction areas to ease handling, table stands and more was added to keep a market that everyone probably already knew was lost. The last slide rules produced were sometimes monsters - or beauties - depending on your personal preferences. I, myself, think that the Faber-Castell 2/83 N (the N is important here) is a beauty. It is the longest 1 foot SR produced, I think. It has 30 scales and it even smells good!
Another favourite is the little FC 67/38b 400 grad Tachymeter. It is a favourite mostly because it is so enigmatic. What are sin.cos and cos2 scales used for? They are probably there for some very valid reason - as is the 1-cos2 scale. Anyone that has information about these scales?
Collecting slide rules appears to be the retired engineer's perfect hobby. We know a lot, but not all, about the objects. We can appreciate the good workmanship, the precision, the artistery and the ingenuity that went into their design and production. And we know how to use them!
There are a few other reasons that make them ideal collector's objects: They are no more produced. They are still available - although in limited quantity. They are not bulky - can be carried with you when meeting like-minded. There will probably never be a fake slide rule - it takes a very complex production facility to make slide rules and the last factory was closed in 1975.
It is a little like collecting Fabergé eggs - only so much cheaper and more interesting.
Comments and answers invited! Do you collect slide rules? Do you have specific knowledge about any special slide rule? What makes do you know about? How do you find them?
BHP = Before HP.
You are invited to share views and thoughts about slide rules. I have been collecting these devices on a rather small scale and had fifteen of them when my collection took a quantum jump. I was visiting the local book store to buy a book on flowers (yes, flowers) when I happened to ask the store-keeper if he perhaps had any slide rules. He gave me a puzzled look and then said "Yes, I found a box with some forty old slide rules yesterday. I haven't decided what to do with them yet".
Need I say that I saved them from the scrapheap? I got a substantial addition to my collection at a price that we both were very pleased with. He because he got anything at all and I because I paid about a tenth of what I had expected to pay.
I have mostly European and Japanese slide rules. Faber-Castell, Aristo, Sun-Hemmi and some less known makes like Graphoplex (French), Diwa (Danish), Royal Slide Rule (British) and Eco Bra (can't make out from where it comes).
There is a certain standardisation among slide rules. There are the scale systems; Mannheim, Rietz, Darmstadt, Electro, Disponent and some other special systems. There is one that intrigues me. It is called Tachymeter and seems to have been used by surveyors. And there are probably many more that I haven't discovered yet.
The slide rules from the BHP era look very much the same except for the introduction of the Duplex slide rules in the late fifties/early sixties. That was also when some colour was added - except for the "reversed" scales (increasing from right to left instead of from left to right) which seems to have been coloured red for a very long time.
It was only AHP that design people started to make the slide rules more and more attractive. Mild colour coding, more scales and cursor lines, extra functions, friction areas to ease handling, table stands and more was added to keep a market that everyone probably already knew was lost. The last slide rules produced were sometimes monsters - or beauties - depending on your personal preferences. I, myself, think that the Faber-Castell 2/83 N (the N is important here) is a beauty. It is the longest 1 foot SR produced, I think. It has 30 scales and it even smells good!
Another favourite is the little FC 67/38b 400 grad Tachymeter. It is a favourite mostly because it is so enigmatic. What are sin.cos and cos2 scales used for? They are probably there for some very valid reason - as is the 1-cos2 scale. Anyone that has information about these scales?
Collecting slide rules appears to be the retired engineer's perfect hobby. We know a lot, but not all, about the objects. We can appreciate the good workmanship, the precision, the artistery and the ingenuity that went into their design and production. And we know how to use them!
There are a few other reasons that make them ideal collector's objects: They are no more produced. They are still available - although in limited quantity. They are not bulky - can be carried with you when meeting like-minded. There will probably never be a fake slide rule - it takes a very complex production facility to make slide rules and the last factory was closed in 1975.
It is a little like collecting Fabergé eggs - only so much cheaper and more interesting.
Comments and answers invited! Do you collect slide rules? Do you have specific knowledge about any special slide rule? What makes do you know about? How do you find them?
BHP = Before HP.
Gunnar Englund
www.gke.org





RE: Slide Rules. Collecting and discussing.
I'd like the collect slide rules, but my wife already thinks I'm right on the edge of being an enginerd. I think that hobby would throw me down the cliff.
--Scott
--Scott
For some pleasure reading, try FAQ731-376
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
There was a slide rule that I was given some years ago by my old manager at work when he retired (unfortunately I eventually passed it on to someone else who was interested). It was a special one designed to do train performance calculations. Before computers were available, in the railway traction field the ratings of the machines were calculated over a particular route by several people working together solidly for a week or so with their traction calculators, in order to get RMS values of motor current etc.. I am not sure how the slide rule differed from a conventional slide rule, also I don't know who made it. Sorry I can't be more specific.
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
I have seven, mostly aluminium alloy Pickett. Three of these are "mine" - purchased new, with the intent of using them on the job. The others are recent purchases from E-bay.
As a college freshman, bought the first one, a 10 inch, top-of-the-line, Pickett Model N4-ES Log Log. Used it thoughout college and on my first job. It has 34 scales, but that is somewhat misleading. Pickett had a unique way of displaying the scales by folding them. For example the Square/Square Root scale is 20 inches long (two scales at 10 inches each).
I have always been proud of the fact that I used every scale on this rule, at least once (and sometimes only once, such as the hyperbolic cosine & hyperbolic tangent scales).
Because of the all metal construction, Pickett rules required routine maintenance. I remember taking the disassembled rule to the college dorm bathroom sink, washing it with dishwashing liquid, reassembling it, and lubricating with Vaseline - all per the manufacturer's recommendations. One other thing, this rule is yellow (the "ES" in the model number is an abbreviation for "Eye Saver"). Pickett offered both white & yellow rules, but promoted the yellow color as easier to read.
The other two rules that I obtained in the "old days" are both circular. One is a very small Pickett, the other is a nice plastic Concise. Turns out that I never used either one of these very much - they have very limited capability (fewer scales) and the concentric scales get smaller (less accurate) as you move toward the center. It is also a nightmare to keep the cursor & scales lined up.
For the E-bay rules, one is a Pickett Model N4P-T Log Log. This is the 6 inch (pocket) version of rule described above. It has the same 34 scales.
My wife gave me 20 inch long K&E a few years ago - I always admired one of my contemporaries who used a 20 inch rule and could get positive 3-digit accuracy, even when working at the extreme right end of the rule.
The 6" Pickett Model N600-ES Log Log is the type that went to the moon, literally. This model rule was carried by astronauts on all Apollo moon missions.
The final Pickett is a basic Simplex Trig rule that I gave my wife - she knows how to use a slide rule, too.
I still use the "big" Pickett from time to time, mostly to impress my continuing education students and other younger engineers. However there is still a lot of value to being able to do what I call the "approximate mental math" needed to use a slide rule effectively.
Thanks, skogsgurra, for starting this Thread!
www.SlideRuleEra.net
RE: Slide Rules. Collecting and discussing.
http://www.svpal.org/~dickel/OK/OtisKing.html
http://www.oughtred.org/
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
The Stealth Bomber was the first aircraft designed there with computers. The others including the U2 and the Blackbird were designed using slide rules for all the calculations. He said that slide rule accuracy was all that was needed for all this work.
In an earlier thread, I commented that the author Neville Shute, in his day job was an aeronautical engineer. He worked with Barnes Wallace at Vickers. He describes all the calculations done on 6ft slide rules with teams of 3 checking each other.
Unfortunately I have lost all my slide rules. I remember one made from bamboo that would jam unless you forced it open with a finger in the middle of its back.
RE: Slide Rules. Collecting and discussing.
That was designed in. All wooden SRs were built like that. The "Three Finger Grip" (thumb on D and index on A with long finger beneath, pressing slightly upwards) was among the first things taught in SR classes. I think that it was to keep the slide steady in the frame. A sliding slide would be most irritating and given that wood (or grass, which I think that bamboo is) is hygroscopic and swells cross fibre, it would be difficult to have a "just right" friction under all weather conditions. So, by making the frame grip the slide and machining a slot at the back side the problem was solved. High friction when needed and low friction when moving the slide. Plastic and duplex SRs didn't need that.
An interesting variation can be seen on Graphoplex SRs. They have two little balls with springs and adjustment screws inserted in the frame. Friction can be adjusted by setting the screws. Metal SRs had to be cared (read SlideRuleEra's description) and greased with vaseline. Vaseline is also used with plastic SRs.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
--Scott
For some pleasure reading, try FAQ731-376
RE: Slide Rules. Collecting and discussing.
http://
http
www.SlideRuleEra.net
RE: Slide Rules. Collecting and discussing.
I get a kick out of reading things like "I've heard stories about them" and "It was my grandfather's". How time flies when you're having fun!!
RE: Slide Rules. Collecting and discussing.
I read somewhere that Reginald Mitchell (died 1938) estimated the top speed of all his aircraft to within 5%. That definitely is within sliderule accuracy.
Once of my instructors at college in the early seventies claimed that people were writing out ten digit dimensions on drawings. This problem must have disappeared quickly because I never saw it.
JHG
RE: Slide Rules. Collecting and discussing.
TTFN
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
Would that be a 62/82 or 62/83? One of my favourites.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
Sadly, that was the same yr that the HP-25 was introduced, so I never really used it much.
TTFN
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
I guess I could console myself with the ol' "Size doesn't matter" and "It's not what you have, it's how you use it" routine - but I've never used one! I've had calculators since elementary school. This thread has renewed my interest in learning, though.
It was made in Japan, and has A, B, CI, C, D, S, L, and T scales, with a semicircular magnifier. I also have the original box, the instruction booklet and a leather carrying case. My guess is my father-in-law got it sometime in the 1950's, either as an engineer in the U.S. Army, or as a Chemistry undergraduate.
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
All bamboo rules were made by Hemmi - that goes for Post as well as Relay.
A Miniature Slide Rule Relay No. 403 is not bad at all. Can be seen at 30 - 50 USD on the net.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
I happened to hear from a friend that there was an old book store only 200 miles from where I live and that there were around 50 slide rules there. So I went there yesterday. The guy was willing to sell and had summed up the original prices (from around 1970) and then he gave me a 50 percent rebate! I refused and payed him 100 percent. It was still a bargain. Found a Faber-castell 62/83 N (their pocket version of the top performer 2/83 N) and several other nice SRs. Also found eight with missing cursors - which made my day a little less fantastic. But still, 41 new ones, that's not bad.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
I think I'll stick with model trains and planes. I just go to the corner hobby shop for those.
<Hoping you enjoy my satirical nature.>
--Scott
For some pleasure reading, try FAQ731-376
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
ht
TTFN
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
Google only came up with two hits, both from the same site. I know just enough German to determine that it was a relevant hit.
TTFN
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
You should be able to tell us all about the history of mechanical calculators.
RE: Slide Rules. Collecting and discussing.
I certainly would like to do that. But I think that the band-width would be suffering. Also, I think that there are limits to the length of postings. And - I'm still learing - not an expert.
But it is an interesting subject. Why not start telling us about your slide rules and calculators - mechanical or electronic? Which ones do you have? What do/did you use them for? How did you get them?
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
htt
Is there a Swedish Google?
TTFN
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
As I’ve stated before I liked the slide rule in meetings as you know that you were in trouble when half the group whipped them out after you had made a statement. We the all the stuff on the table today you never know what anyone is doing.
Also as stated before I got to work on the first engineering application on the IBM 360 at work.
The first multiple purchases of utility electronic calculators that were made by Singer, the sewing machine company. The display was nixie tubes. This was later change to a CRT.
While overseas I knew there were about 20 IBM tabulation machines in operation on the base but didn’t find out until later that there was mainframe working 24/7/365. Don’t know the make but it was big. One of the guys who worked with it told me many years later that if they lost air conditioning it cost about $80,000 to replace tubes and relays. This was in 1957.
It has been interesting watch the evolution of computing in engineering over the years from a very ragged start. When in college taking algebra I remember that we skipped over Boolean and Matrix Algebra. The comments were that we would never need it and if we wanted to we could take it as graduate course in our senior year, if we had time.
Most of the people on this site missed the best part of computing.
Like a lot companies we suffer with management that consider a computer a luxury and wasn’t needed by engineers. When we did get one or two 10 megs of memory was something else. A little later when one could get a math coprocessor, king of the road. I started with Visicalc and Electric Pencil, a spread sheet and word processor what more could an engineer want. After the 286 machines got a little more RAM a few usable program began to emerge like Lotus 123 and Symphony, which I still use occasionally. I broke in on Me10 from HP in the drafting department. I helped get the first real package engineering programs at a time when we only had home built programs like an ASME Flange program and a few piping programs. The package programs for the engineering group were Compress, buggy and you had to hit enter or you were in DOS . Pipe Plus, we tried to run a gas manifold on a 286 the IT dept had taken the coprocessor out. 24 hours later we were still reducing the matrix. When it finally stopped we couldn’t display the results on screen. I had the first MathCad, It was a bear it didn’t handle units and any mistake kicked you out to DOS losing everything. Oh for the good old days.
We used a lot IMSA kits programed by wiring to do specific functions. There were still 4 in storage along with an original HP Signal Generator with a single digit serial number.
My first home computer was a Sinclair then several by Timex. Finally worked up to the TI 99-4A, first one was $999 and the last one was $49.99 as they got out of the business. They still work. Never did much work but had some nice games. It did teach you to write tight code. Later when I got a 286 Gateway, $2495 + 250 for coprocessor + $250 for 10 more megs of memory + $125 for 128K more ram. I soon bought and started using Pro Design for drawing and when they got BasiCad for programs and macros I could write some very tight code. I still use a lot of these programs to draw tubesheets, flanges, cabinets, bookcases and such. Still in DOS never switch them to VB.
RE: Slide Rules. Collecting and discussing.
You got started a little, but not much, earlier than me. The BIG difference is that you obviously started in an environment where computers were actually needed (even if you didn't get that impression first).
I started as a drive's designer with ASEA Västerås in 1963. That was slide rule territory. 100 percent. My first exposure to computers was an HP 1000 with TTY 33 (yes, 110 Baud and paper tape) and I think that it must have been around 1972. It swept me away. WOW! What a fantastic thing it was! We practiced algorithms and lean coding a lot. And execution speed. We had fun.
The first exposure to microprocessors was the intel 4004. We had two systems; the small system with 768 bytes of EPROM and the "big" system with 1280 bytes. Yes, bytes. What else?
Hand assembly and manual entering of HEX code into a ProLog programmer for 1708's. We still had fun. Then we got an MDS system. With 8 inch floppies that were real floppy. Error messages that just flew by on the screen so you could only read the last ones. Assembly could take an hour on that system. But no hand assembly any more - we thought it was great.
Then came the 8080, 8085, Z80, 6800, 6510 and the 6502. That is where I met FORTH. What a relief. How elegant. Work wasn't work any more (yes, pun intended) it was pure joy.
The early 8-bit micro computers (yes, I remember VisiCalc and The Electric Pencil - I even remember the ads with a guy hugging a pencil) had some quite good software. And booted in a split second. Have the Mega and Giga-everything devices really added value to life? Yes, perhaps. Downloading pdf would not work in those days. But sites like Eng-Tips would have been possible. BBS with nothing but ASCII worked quite well.
Oh, I think that I got carried away a bit. It was supposed to be about slide rules and calculators. But I think it was about eight-bitters mostly. Except for the 4004, which was a four-bitter. Cycle time was 10.8 microseconds and it took - I think - six such cycles to store an eight bit word in two consecutive memory locations. And we still did some quite good real time control with it. Not much checking or redundancy, though.
Let's hear about other members' experiences in these fields.
BTW, to get back on track: I received a Faber-Castell 8/10 circular slide disk calculator today. Just beautiful. Found one for about 25 USD. Not bad for such a beauty. MIB with instruction leaflet. Happy.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
We had a Macrodata MD-104 memory tester that was programmed via paper tape. We'd sit on the ASR 33 and type in the codes, but if we made ANY mistake, we started all over again. Thank goodness we finally found a way to do electronic editing on a different paper tape puncher.
Anyway, senior yr in high school, we had something called Engineer's Week, and I got an honorable mention (not sure what I did to compete, tho.), which was rewarded with a brand-spanking new Pickett aluminum slide rule in a faux leather case. Really nice... Unfortunately, I had already pestered my mother into sinking $150 for a TI SR-50. Whoa, momma!!!
Of course, merely 1 yr later, I was pestering her for another $150 for an HP-27, which was programmable, and therefore, infinitely better.
TTFN
RE: Slide Rules. Collecting and discussing.
Yes, a mother's love used to be an infinite source of new gadgets. And still is. Although it is my children's mom we are talking about nowadays.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
Looking at some of my fathers books from the 20's very complex mechanical problems are resolved by a graphical solution using only algebra, trigonometry, and geometry and of course the logs. He had solved some very complex mechanical motion problems using graphics and plotting some of the results.
f you carry this theme further to when you and I began our careers the slide had became more readily available and usable, but the one thing left out of most discussions is the profusion and availability of good technical graph papers. A slide rule and the proper graph paper were a potent combination in resolving fairly complex problems. The engineering group had a very large cabinet with every conceivable type graph paper and in another area the process group had another cabinet with a slightly different inventory. Graphing was the spreadsheet of the day. Every engineer had to attend a production chart (graphs) meeting at least once a week where as the production group went everyday. After accounting the quality control group got the first shot at all new computer technology and really went wild when they could start doing some statistical control functions. Changing the scales and limits to fit the data and making their point.
As I’ve stated my first engineering application on a main frame was the expansion of the McCabe-Thiel diagram. To develop the data to have punched into the computer we took numbers off an existing diagram, used a slide rule to verify that point, ran the program, reploted the diagram, then took more numbers off the new diagram and then took the slide rule to convert them to useful engineering functions.
You see a lot of recommendations on this site recommending that a particular problem be modeled. Well we sometimes modeled a problem graphically by using multiple axis and scales to see where two functions converged or diverged. I have extrapolated data by eyeballing a curve through a raft of plotted data and then using the resultant curve for data points in slide rule calculations. All with what must have been pretty good accuracy as some of the equipment is still running after 40 years.
I just visited an office supply store and they had exactly two types of graph paper. Up to the mid 80's our companies standard engineering work sheets and log books were printed on grid pattern paper. By this time we were telling new engineers that the grids were to make them write legibly.
You probably remember that the 6" pocket slide rule stayed around for a few years after the larger rules dropped out. They didn’t start disappearing until the personal multifunction calculators could extract a square root. They were all gone when the nat log scales came on the scene.
RE: Slide Rules. Collecting and discussing.
We've got a beaut of a nomograph for one particular problem in TV performance modelling against an airborne target. There are actually 9 (yes, nine) 2-d graphs on a single 11x17 sheet of paper. You start on one graph and follow the directions through the other 8 in sequence to determine the design requirements given the target and atmospheric transmission. There's log-log, semi-log and linear graphs all in the same nomograph. It's truly a thing of beauty...
It's also quite sad to see those 5 and 6 place logarithm tables languishing in the used book stores.
TTFN
RE: Slide Rules. Collecting and discussing.
I once had a very good shareware program named "GraphWriter" in one of my computers. I had even paid a small registration fee for it. But now I cannot find it out there. Wasn't it GraphWriter? Or was it something else? I loved it. Could do anything - and is probably a lot more universal today. Anyone knows about it?
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
h
Dogpile came up with a bunch of hits:
http:/
TTFN
RE: Slide Rules. Collecting and discussing.
No. Not one of those. This, I think, was a Swiss or French guy that had made a very nice program for all kinds of graph papers. For calendars, music, smith charts, lin/log, log/log, weibull and what have you. I may be mistaken abiut the name. Will search more some other day. Now we are off to search for slide rules in the flea markets of western Sweden. Wish us luck!
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
http://www.marquis-soft.com/
TTFN
RE: Slide Rules. Collecting and discussing.
Do not do this too often - I may forget how to find things
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
Here is an intersting link, they have a rule on a wrist watch. http://www.sphere.bc.ca/test/sruniverse.html
I have a K & E, 68-1251 Log Log Duplex Decitrig Rule with leather that I recently aquired. Willing to depart with it if anybody wants to barter.
When I was in college we were restricted to calculators with no more than two memory registers, A and B. What a comparison to current mobile computers and yesterdays slides.
Today you will have to pry TK Solver "from my cold dead hands"!
_______________________________________
Feeling frisky.........
www.tailofthedragon.com
RE: Slide Rules. Collecting and discussing.
My main sliderule in college was a 10" K&E Decilon plastic rule. Plastic was very good in the humid and hot deep south. Nothing like going to a test, and it rained that day, and your bamboo slide rule was swollen and stuck.
I transferred to the university from which I graduated from a military academy where I had been issued the K&E. The predominant rule where I finished was Post with a smattering of Picketts. I could work circles around the Post guys with my K&E. Those natural log scales were wonderful. (not that I could use them today)
When I graduated I did not want to carry that 10" on construction jobs, so I got a 5" K&E Decilon in a pocket carrier with clip. I used it until I got my first HP which was a 35 or a 55, I can't remember. It had a 10 step programmer. Thought I had died and gone to heaven.
Wnen I bought the HP, it cost a months salary, and wouldn't really fit into any pocket except the inside pocket in a suit jacket. I didn't wear suits to work, but I did wear a tie.
The company wouldn't buy us the calculator, so those that had one in our engineering dep't used their own personal equipment. So, when we had a really big crunch project, I would show up with my slide rule. It infuriated the chief engineer that I did not bring in my calculator that day, but since they wouldn't issue me one, it was my choice.
Now, an interesting story: when at a Plate Hx conference once in the early '90's, I made a statement contrasting some design differences between them and shell and tube Hx's that had to be remembered, mentioning in the process that I had had some shell and tube design experience in a previous life.
At the dinner that followed, a young engineer sitting next to me made the statement; 'I remember you...you were the one who said he had a S&T design background. Did you use B-Jack?' To which I answered "no, I used a slide rule." He replied 'I have heard of those.'
I have a client about my age who commented to me once "every now and again I get my slide rule out of the drawer and throw it up on my desk just to remind me of who the heck I am." I now do the same from time to time.
I also have a simple Post slide rule that I used in High School, and one other one that I could not find which is a 4" or a 5", again, with very few scales.
I also have a Fisher valve sizing slide rule. Remember those?
rmw
RE: Slide Rules. Collecting and discussing.
I also have a circular compressor-sizing slide rule that I still use every day. I've never thought of it as a "slide rule", but it is. I've got the arithmetic that it uses built into a MathCad file, but I find the slide rule a lot easier to get right.
David
David Simpson, PE
MuleShoe Engineering
www.muleshoe-eng.com
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
The harder I work, the luckier I seem
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
One is from high school. It is only a little 6” long plastic one. I kept it and later used it to calculate gas mileage. (That was when we still thought of gas mileage in MPG and bought the stuff in liters and had the odometer in kms, so a little conversion was in order.) Many a gas pump attendant looked on in disbelief that a stick could be used to do calculations.
I have a cheap circular one from when I took my pilot’s license. It has the basic scales on the perimeter and can do vector addition on the circular part. (wind and velocity vectors to give true ground speed and heading)
Finally I have a Geotec Versalog, a true engineering slide rule. I bought it when I started university in 1973, paid $CDN 100 for it and used it until Christmas when I got my first calculation, a Commodore model that only had the basic four functions plus square root. I still carried my slide rule and used it to look up trig functions, until I got a full featured calculator a year later.
Rick Kitson MBA P.Eng
Construction Project Management
From conception to completion
www.kitsonengineering.com
RE: Slide Rules. Collecting and discussing.
http://www.hunterproducts.com/calculator.htm
RE: Slide Rules. Collecting and discussing.
I am still curious about strange slide rules that you may have - or have used.
I have one circular one (square plastic with circular scales and a "hand" that serves as a cursor. It has a scale system that goes from 0.01 up to 1000000. Yes, one hundredth to one million and you can do calculations on it without having to keep track of the decimal point. At least as long as you do not leave the 0.01 - 1000000 range.
It is marked IWA 1638 system Wern. You guys ever seen one of those? Any historical data?
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
http://www.sphere.bc.ca/test/aristo.html
http://www.sliderules.clara.net/index.htm
RE: Slide Rules. Collecting and discussing.
ht
Enjoy!
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
Would that be Kilsta, Björneborg or Granbergsdal?
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
BTW, I visited a couple of slide rule designers yesterday.
Yes. It is true. They have designed lots of specialised slide rules for HVAC and similar applications - but also a circular slide rule that was produced in large numbers by the German company IWA.
I found one of those circular slide rules in a stationery shop this summer. All that was printed on it was System Wern IWA 1638 Made in W. Germany.
Some research led me to a German site where IWA was mentioned and from there I found a reference where i could read "von einem Schwedischen Ingenieur Wern konstruiert" (designed by a Swedish engineer named Wern).
I got this wild idea; is he still alive? After quite a lot of research, I found his niece in southern Sweden. "That must be uncle George" she said. If he is alive? "Yessir! He and his brother Carl live in Stockholm."
So I went there to have one of my life's better interviews. Two absolutely stunning 80+ year old gentlemen that had all the history and all documentation on their shelves. Even a specially designed machine for producing the masters!
I will write an article in the Journal of Oughtred Society about it. And guess what? I had a very nice addition to my collection when I left the brothers - Two MIB 1639, a set of unique HVAC slide rules from around 1970, marketing material, manuals and other documentation.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
The May 2006 issue of the Scientific American has a well-written article "When Slide Rules Ruled" by Cliff Stoll. It is a good introduction to slide rules and also about the historical development. The ending words (a slide rule talking to a PC) are worth pondering: "Watch out! You never know when you are paving the way for your own successor."
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
http://www.sciam.com/media/pdf/Slide_rule.pdf
...and I made one, and here it is
Accuracy is not too bad. Here it shows 12.2 x 17.8 (or wherever you want to put the decimal point) = 215 (versus a precise 217.16)
www.SlideRuleEra.net
RE: Slide Rules. Collecting and discussing.
Meanwhile out IT people were driving everyone crazy making sure we were ready for the end-of-civilization-as we-know-it.
I still carry it in my briefcase for those times when the calulator or laptop batteries fail.
Interestingly, this slide rule cost me about about two days pay, at the time (just out of high school). Now, two days pay will buy one one my kids a PC.
RE: Slide Rules. Collecting and discussing.
I got one sone years ago that calculates the volume of cylindrical vessel with flat ends, domed ends (concave or convex ON ITS SIDE like you would have with a storage tank.
You dial in the dimensions (Metric) the actual depth of liquid & it gives the answer in a whole range of umits from cobic metres & feet to barrells & gallons (both US & IMPERIAL)
on the otehr side....it does rectngular tanks
The company FEARNS was in Gateshead in the UK.
They also did calculator factorpacks with multipications factors that convert any unit to another - these were produced when electronic calculators were introduced.
Ive got one & its a trusted possesion. One guy I worked with programmed this data into a spreadsheet on a PSION pocket computer - which made a very sophisticated calculator...
My first real slide rule was a Faber Castell double sided one which was far better that using log tables !
Remember log tables.....this was all OK till I got into 7 figure logs.
Bruce L Farrar.
Works Engineering Manager
Marshalls Mono PLC.Brookfoot Works.
Halifax W.Yorks UK
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
"Muffley:
How long would you have to stay down there?
Strangelove:
Well let's see now ah, searches within his lapel cobalt thorium G. notices circular slide rule in his gloved hand aa... nn... Radioactive halflife of uh,... hmm.. I would think that uh... possibly uh... one hundred years. On finishing his calculations, he pulls the slide rule roughly from his gloved hand, and returns it to within his jacket.
Muffley:
You mean, people could actually stay down there for a hundred years?
Strangelove:
It would not be difficult mein Fuhrer! Nuclear reactors could, heh... I'm sorry. Mr. President. "
Peter Sellers was a genius...
I wonder what "cobalt thorium G" is...
RE: Slide Rules. Collecting and discussing.
I'm watching Apollo 13 on TV this evening (commercial right now) and they are right in the heat of the moment of trying to recover from the accident, and look at those boys in mission control zapping those slide rules.
That was 1970 and I was still toting my slide rule to classes at that time in my life.
What a reminder.
rmw
PS: sorry Skogs, I just scrolled up a couple of posts and noticed your note about slide rules in movies. Well, there they were. Sorry commercial is ending and I am on the edge of my seat. I hope these guys make it.
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
RE: Slide Rules. Collecting and discussing.
There was some mentioning of circular slide rules in earlier postings. And now, there is a Wern 1638 (circular with unique properties) for sale on ebay. Please don't bid! I want it!
The reason that I want it is that I have researched the Wern calculating disks rather thoroughly. And I actually met the Wern brothers. They are still active (age 83 and 83+). I also wrote an article about the 1638 in the Journal of Oughtred Society and the issue containing that article appeared this week. I guess that is bad timing - price of the 1638 may increase a bit when people see how good it is...
Anyhow, I think that we should start a new thread where slide rules and other calculating intruments appear in papers, movies, poems(?) and novels.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
A tachymeter for surveying os a mind of theodolite, and not similar to a slide rule.
A slide rule type tachymeter is something different. Some watches have them around the bezel. It is a kind of circular slide rule that relates time, distance travelled, and speed.
RE: Slide Rules. Collecting and discussing.
I had a Wilde theodolite, a book of trig tables, a field book and the Curta. A few dozen revolutions and the answer appears ready to record in the book.
Now I believe the theodolites communicate with the engineering office and roads are designed before you ride the horse back to basecamp.
I may buy a couple on eBay just as an investment. Wonderful machines.
RE: Slide Rules. Collecting and discussing.
I also used an E6B circular aviation calculator extensively while flying. If you're not familiar with these, in addition to the normal time-speed-distance stuff, they have conversions for pressure altitude, true air speed, etc., plus a handy way of playing with the wind's effect on flight path.
I still have a Picket 10-10-ES in the desk that I take out on occasion to a: do a quick calculation and b: prove a a REAL dinosaur I am...
old field guy
RE: Slide Rules. Collecting and discussing.
I have a device called E6-B2 Computer. Same as yours? It is in aluminum and consists of a round part with two circular scales with three windows in it. It slides on a rectangular part with scales and formulae on it. Plus a very impressive set of lines and arcs. There is even a locking lever.
I have no idea how to use it - it is just a very impressive piece in my collection.
Have a look at the Wern 1638 at ht
It is a beauty - isn't it?
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
I was fed up with the 4th grade arithmetic. Day after day, page after page of long divisions and 3 and 4 digit multiplications. Pure drudgery. As if solving more problems, after the principle had been learned, was of any value. Not that I couldn't solve them, but why? I did a couple days' worth, got them all right, I'm ready for something new. But not the school system, nooooo. I so despised those pages of drudgery at the time, that I wrote down random answers, rather than submit to the drudgery. And being a bad boy was fun and I started other bad behaviors.
My dad, seeing my marks go from A's to F's and getting a note from the teacher, asked me what was going on. I told him, he agreed that doing mountains of long division problems was stupid and said, "we'll fix that". He got out a slide rule and proceeded to show me how the log scales add up (cool concept) and how to multiply, divide, and do square roots.
Taking an expensive engineering slide rule to school wasn't necessary, so he drove me down to Cy's drug store and he bought me a small 5" or 6" cheap, plastic slide rule that was in amongst pens, pencils and rulers on the stationery shelf. It fit in my shirt pocket (probably the same model Rick Kitson RDK mentions above). I think it was $0.29 at the time (1960, and no sales tax in Erie county). I used that slide rule in class, day after day, effortlessly completing the problems in a matter of minutes, and then read a book for the remainder of the arithmetic session. I actually took that slide rule to Sundsvall in 1967 as an exchange student, and used it in Fröken Hunewall's chemistry class.
No, the 4th grade teacher never said anything. I suspect now that she didn't know how to use a slide rule and was afraid we 4th graders would find out, blowing her goddess authority cover. She left me alone.
Great things those slide rules.
Dan
RE: Slide Rules. Collecting and discussing.
No - I do not know her. But sounds quite good. What about Sundsvall at that time? I remember staying in Hotel Knaust around 1965. Their salmon in paper was really superb.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
That sounds like the animal...
The sliding rectangular part allows you to interface a wind vector with your flight path to determine ground speed and correction angles.
They're quite the handy little trinkets in flight planning and management. Plus, the batteries NEVER run down.
old field guy
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
When the first $600 compact computers came out, we shared it in the eng dept. It was the HP with reverse polish notation; very cumbersome.
RE: Slide Rules. Collecting and discussing.
In college, one of the guys had this monster 12" diameter rule, That equal to a 3 foot long rule, 4 or 5 decimal places near 1.
RE: Slide Rules. Collecting and discussing.
Thanks.
RE: Slide Rules. Collecting and discussing.
I have several slide rules in duplicate, triplicate and even septuplicate (if there is such a word).
I am holding on to them passionately, but someone who expresses a need for one like you do should contact me. I have a distinct feeling that price will not be an issue...
You may have to do some detective work (easy) if you want to contact me. Please put SLIDE RULE in the subject line. Norton throws most other mails away.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
I have a nice condition Keuffel+Esser 68-1251 with orange leather case for sale if anybody is interested??
==========================================
Business Card http://mech.e.tripod.com
__________________________________________
Cycle Heaven.......www.tailofthedragon.com
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
They sell between 1000 and 2000 USD on eBay today.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
Thanks for the interesting discussion on slide rules. I only had the chance to use one (circular) in a physics class. This was in 1976, so calculators were coming around. I have to see if that is still at my mom's house.
I did find a Pickett Model 1000 at work and based on some links from this discussion have found some info on it and am in the process of teaching myself how to use it. I hadn't realized how much I had forgotten in terms of math on a guesstimate of magnitude the answer is (ie where is that decimal point?) It is fun!
One question, is apparently some of these were made in magnesium and later changed to aluminum. How can one tell the difference?
it is a bit hard to slide so I think I will try putting vaseline on the slide based on SlideRuleEra's posting.
RE: Slide Rules. Collecting and discussing.
On my Al rule I just changed the lubricant to extremely fine Boron Nitride.
RE: Slide Rules. Collecting and discussing.
http://
RE: Slide Rules. Collecting and discussing.
Yes, right. And also very nice objects in general. I met a collector in Paris a few weeks ago. He had some really (I mean REALLY) nice things in his brief-case, like a Charpentier in original case, an Otis King, a waist-pocket clock/slide rule (five or six known world-wide) and a Bavarian circular with automatic decimal point locator. We remained sitting in that Bistro "manipulating" till they closed. And then continued in the hotel lobby.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
do have any pictures or links on the rare waist-pocket clock/slide rule?
Must have been a great time!
RE: Slide Rules. Collecting and discussing.
First the combined clock/slide rule. Please note that Sigismond's is as near mint as you can get while the one shown in the Oughtred Society paper has some stain on the scales.
Sigismond also has a very fine Charpentier - in original case!
And, with original "Mode d'emploi"!!!
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
I'm sure you know that MIT got the K&E collection. I've seen on some sliderule sites where some people have been privledged to see it. I hope they plan an exhibit soon of them.
A star for the pics!
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
Yes, that is where I had seen it also in Journal of Oughtred Society. I'm in Vermont, so it will possible to go view the collection when it is put on exhibit.
I'll have to look at the IKEA catalog for the wardobe cabinet when my collection increases...or go for a visit to the store...great excuse for the meatballs they serve!
RE: Slide Rules. Collecting and discussing.
I'll let you in on a secret: My wife makes a lot better meatballs than theirs.
The wardrobe is from the PAX series. Looks like this:
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
I think I spotted you on my map - Burlington?
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
I have had lots of Swedish meatballs via Minnesota. Do they make Swedish sausage in Sweden or is that a Minnesota invention. Like most sausage I'm not sure what all went in them but they did have a lot of potatos. Very good.
RE: Slide Rules. Collecting and discussing.
The “Nónio” of the Portuguese mathematician Pedro Nunes appears in the book “De Crepusculis”, published in 1542. In the second part of this workmanship, the proposal number three, prayer thus: "To construct an instrument that is very appropriate to the observation of stars, and with which one can determine the respective heights rigorously".
An astrolabe is an instrument used to measure angles. About 500 years ago, Portuguese navigators who discovered the islands of the Azores, Cape Verde and Brazil used the astrolabe so that they would not get lost at sea. Using the astrolabe they were able to calculate their position on earth by measuring the angle of the Sun above the horizon.
Sextante of Gago Coutinho, portuguese pioneer pilote who first aplpy the sextante in aerial navigation.
Cheers
luis
RE: Slide Rules. Collecting and discussing.
Skogsgurra,
Do you have this book.
Philip E. Stanley, A Source Book for Rule Collectors (Mendham, NJ: Astragal Press, 2003) ISBN 1-931626-17-0. Enquire at Astragal Press, 5 Cold Hill Road, Suite 12, P.O. Box 239, Mendham, New Jersey, 07945-0239, or at Astragal Press. The book is accompanied by a Concordance and Value Guide, of interest mainly to collectors. The current price is $45.00.
RE: Slide Rules. Collecting and discussing.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
There is another article on slide rules on this page. The article on Descriptive Geometry brought back some tough memories from school.
http:
These are a few of the informative articles from the site of Dr. James Calvert.
Anecdotal:
I had to take 2 quarter of Descriptive Geometry from a very knowledgeable but poor teacher. He would hit the class draw a few lines on the board along with one or two instructions and leave. In my second quarter the remaining students, mostly Korean War Vets got tired of his teaching approach and one day grabbed him and held him out the 3rd floor window and asked him to change his ways. Fortunately for all of us he started doing a little more explaining of the methods use in Descriptive Geometry. Somehow I managed to ace my final, a mine slope and intercept problem and get good grade for the course.
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
...sure brings on the "stares" when I haul it out!
RE: Slide Rules. Collecting and discussing.
In one of the drawers that I rarely opened, I found an ACU-MATH Mannheim type slide rule in a card board box, "the original box." together with instructions on how to use it.
It is a mystery to me how I came by this, because the one I always used to use was a K&E. Which of course I can now no longer find.
These all got shoved into drawers when I went to electronic calculators. Every once in a while I pull a slip-stick out to prove I can still use one.
B.E.
RE: Slide Rules. Collecting and discussing.
FRONT Fixed
K X^3
T1 tan0.1X
T2 tanX
DF PIX (folded scale)
FRONT Sliding
CF PIX (folded scale)
CIF 1/PIX
CI 1:X
C X
FRONT Fixed
D X
ST arc0.01X
S sin0.1X
P sqrt(1-(0.1X)^2
REAR Fixed
LL03 e^-X
LL02 e^-0.1X
LL01 e^-0.01X
W2 sqrt(10X)
REAR Sliding
W2 sqrt(10X)
L 0.5lgX
C X
W1 sqrt(X)
REAR Fixed
W1 sqrt(X)
LL1 e^0.01X
LL2 e^0.1X
LL3 e^X
I also had a similar 12" (it must be around somewhere) that I used throughout my 3 year HND engineering course and after at work (when I wasn't using Inskips Combined Tables!). This slide rule also had a "clip on" glass magnifier for the cursor, much better than the Aristo ones with a "half round" plastic magnifier that was part of the cursor.
Oh happy days..... as long as you remembered where the decimal point went!!!
But on balance the change to the metric system combined with battery powered digital calculators gave an order of magnitude increase in office productivity.
RE: Slide Rules. Collecting and discussing.
And, you are absolutely right wrt the metric system.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
RE: Slide Rules. Collecting and discussing.
Sorry no. I did mine in Cheltenham in the mid-late 60's.
RE: Slide Rules. Collecting and discussing.
I started this thread a little more than two years ago. It has developed well and groown big and healthy.
But it is also quite long. I think it is about time to start a new thread on Slide Rules, calculators, Planimeters (fascinating instruments that I barely can understand) and other such devices.
So, I say good bye and thank you for participating. And welcome to the new thread "Slide Rules, Calculators and other fun stuff"
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...