What is that?
What is that?
(OP)
One of the guys in my office took early retirement a couple of years ago but still does bits of part time work when we are busy. To this day for basic calculations he still uses a slide rule.
One of the junior members of staff came in and asked him what he was doing “playing around” with a rule and when he started to show him he thought he was winding him up, he had never seen or heard of a slide rule. Whilst it has been many years since using a slide rule or log tables, sine tables etc, I guess I just thought people would know what they were.
So am I just getting old (I actually know the answer to that) or what else don’t the up and coming engineers of tomorrow know about? With digital read outs can they still read a vernier, or even a micrometer?
Anyone else been asked what is that?
One of the junior members of staff came in and asked him what he was doing “playing around” with a rule and when he started to show him he thought he was winding him up, he had never seen or heard of a slide rule. Whilst it has been many years since using a slide rule or log tables, sine tables etc, I guess I just thought people would know what they were.
So am I just getting old (I actually know the answer to that) or what else don’t the up and coming engineers of tomorrow know about? With digital read outs can they still read a vernier, or even a micrometer?
Anyone else been asked what is that?





RE: What is that?
I've ahd it a while and don't know if there still made or not. When I show it to people they covet it. IT travels in my breifcase, never stays in my desk
RE: What is that?
However, she had no idea how or why the magic log tables worked. Much like my "X" button on my Casio fx180p.
Slide rules, log tables, calculators... All simply tools of the era.
RE: What is that?
Vernier - no problem
Micrometer - no problem
Slide rule - whassat?
I was born '71.
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If we learn from our mistakes,
I'm getting a great education!
RE: What is that?
Verniers and Mics are not a problem... use them every day.
RE: What is that?
Verniers & mics - sure. I sometimes use them in interviews just to see.
A few months back, I was glad I knew how to read a vernier. I was in the Netherlands supporting some equipment and found myself at a machine shop. I wanted to measure something and the calipers they gave me were verniers. I was glad I didn't have to say, "Uh, I don't know how to use these..."
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RE: What is that?
Till 1979 i.e upto completion of postgraduation only slide rules and log tables were permitted. Infact knew the full table by memory.(did not need to refer!!) Calculators were not permitted as those who could not afford one would be at a disadvantage.
RE: What is that?
Two good ones:
Interpolating sine tables in the field, sweat dripping on the field book, smearing the calcs and a HVAC final taking the BTU used in a year for a house and dividing by the cost of heating by coal gas elec wood etc Dividing millions into billions long hand. plus/minus calcs were way out of reach money wise so none were allowed ( several hunderd 1972 dollars)
John
RE: What is that?
The program was written manually moving point to point using a trig table and movements were about .010 between points.
The programmer calculated about 400 points and then punched a N/C tape manually. Slide rules are too inaccurate for this calculation.
RE: What is that?
One of his favorite jokes is:
An engineer was asked, "what is the square root of 9?" The engineer pulled out his slide rule, fussed around with it a little, then said, "Approximately 3."
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http
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Also the joys of drawing on tracing paper that nearly self destructed with humidity change and the constant smell of ammonia from the printer. I can still remember the major leap forward of moving over to CAD, very basic ACAD 2D and the wonderful printer with the little pens that you had to fill with ink that usually lasted about 10 seconds before giving up and needing cleaning again.
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You dont need to be a genius to reap the benefits of digital electronics. Research publications show curves drawn with only one data point!!
Today chemical labs while giving lab reports give Carbon content 0.4563%. This has no physical significance beyond stating 0.45%, but the digital computer output is sacrosanct and I have witnessed arguments by stupid inspectors.
RE: What is that?
I feel your pain regarding inspectors, I don't know many times we've had to explain to inspectors that a leakage rate of 0.01 cc over the allowable limit of say 10 cc is not a huge deal. Or that a dimension which is 0.001" off the allowable of say 15.000" is probably attributable to the vernier. Stupid accurate measuring equipment :)
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Go Mechanical Engineering
Tobalcane
RE: What is that?
Micrometer - Yes
Slide Rule - Of Course, including scales for Log-Log, Inverse, Sine, Tangent, Sine-Tangent, Square & Cube Roots, etc.
Favorite however is the 1936 (hand cranked, desktop) Monroe Calculator my father gave me in the mid-1960's. Addition & Subtraction are a breeze, just depends on which way you turn the crank (clockwise or counterclockwise).
Multiplication is more fun, you have watch the registers to keep up with the number of times you turn the crank, and you have to "flip" the carriage to move from column to column.
Division in the real eye-opener, turn the crank "backwards" until a bell rings (literally). Then crank one turn "forward", flip the carriage and repeat the process for the next coulumn.
Also you can use "Newton's Method", and with a good initial guess do a square root very quickly.
Accuracy for this basic model, you can stop the process anytime with less however:
Input: 6 significant digits
Output: 12 significant digits
Decimal Point: Do-it-yourself, but there are little mechanical "markers" that you can move around to serve as either a decimal point or commas.
Maintenance: Spray the insides with WD-40 every 3 or 4 years.
I was born in 1947.
www.SlideRuleEra.net
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Go Mechanical Engineering
Tobalcane
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Maui
Constants aren't; variables won't.
RE: What is that?
I have a drawing for a welded wire fabrication,(for a high way project)this is 9 metres long and the accuracy is +/- 5mm!!! I am yet to start on this work
RE: What is that?
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
RE: What is that?
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Hope if you travel south we may meet.
RE: What is that?
Micrometers are daily and I know enough to know that I use Calipers with a vernier scale on them. I do NOT use verniers and do not acknowledge they exist.
Calipers can be used as well as Vernier Scales. I am still trying to figure out what a vernier is (1/100th of a vernier scale?)
RE: What is that?
A vernier dial: a tuning dial in which each complete rotation of the control knob causes only a fraction of a revolution of the main shaft, permitting fine and accurate adjustment.
There are also vernier engines, vernier capacitors, vernier sextants, vernier calipers.
For an example see
RE: What is that?
RE: What is that?
The auxiliary scale is the vernier.