PDA

View Full Version : Slide Rules....Anyone remember them?















woodsprite
31st October 2006, 11:59 PM
Funny the things one thinks about when renovating.:o Firstly, was cleaning up the old mantle piece in the last room to get done, and as I cleaned off the old gunk, it brought back a heap of memories from my younger days...candles burining in the tops of empty port bottles and dripping wax onto the mantle, fag ends scorching the mantle, countless arms of friends draped over the mantle in front of the open fire, heaps of great memories.

And then, for no reason - Slide Rules! Does anyone remember the days of these creatures, and how much fun one could have (or not have) with them? I still have my very expensive Faber Castel? from Form 3, but don;t use it. My 17 year old son couldn't work out what it was for, how it worked, and certainly didn't believe the accuracy of the implement in the hands of a good operator - not me, I had trouble doing additions on the thing!

I guess calculators are more convenient, give better accuracy, and are a heap more versatile, but gee, the old slide rule was fun in its day.

Skew ChiDAMN!!
1st November 2006, 12:22 AM
Yep. Have a 12" Hemmi engineers rule if front of me even as I type. I use it regularly in the shed when making my guesstimates... more to check that I've got the magnitudes right in my mental maths than anything. :o

Far quicker than rummaging through the house looking for a calculator and batteries or waiting for Windoze to boot. ;)


I guess calculators are more convenient, give better accuracy, and are a heap more versatile, but gee, the old slide rule was fun in its day.

Gotta disagree with part of this. They're only as accurate as the numbers punched in. All too often I've read an answer back from a calculator and the ol' grey matter has jumped in saying "that's not right!" because I always run a mental guesstimate first.

On the other hand, the kids'll quite happily accept the answer as given, after all "the calculator doesn't make mistakes." :rolleyes:

jmk89
1st November 2006, 03:34 AM
Yep, like you I still have my Faber Castell from 3rd Form. I still use it for all sorts of things. The best thing is that once you set the particular factor that you are multiplying or dividing by, you don't need to do anything more - just read off all the results. When you are working with a scaling issue, this is a great facility.

AS Skew said, the other advantage is that it is a great check on your numbers to ensure that your order of magnitude is correct. In fact, I use a calculator and a slide rule together - set the rule to check the mental arithmetic and then, if I need the exact number calculate it. The calulator I use is also a legacy of education - it was bought only 4 years after the slide rule when I was doing 1st year maths at Uni. I haven't ever felt the need to update it (although I do use an HP 12C at work).

Daddles
1st November 2006, 09:06 AM
I loved me old slide rule. I did matric when calculators weren't allowed - it was log book or slide rule. I was the only one using the slide rule. Still got about four of them in a bottom drawer somewhere.

Richard

bennylaird
1st November 2006, 09:13 AM
When teaching maths at uni I had a faulty calculator. If a student forgot his I would lend it to him.

if he put in 6 x 9 and it said 42 they would accept it as fact.

Andy Mac
1st November 2006, 09:23 AM
Yep, I used one in high school, and still have it somewhere, in its green sleeve with "Sly Drool" pasted on it:rolleyes:. I think the last time I rediscovered it, 20yrs or so after using it in earnest, I couldn't remember how to do the simplest calculation!! But at least it never ran the batteries flat...

Cheers,

bennylaird
1st November 2006, 09:27 AM
The old fig 4 tables were good too, have not seen a copy for years now.

Makes it hard to teach decibels and logarithmic scales these days as the kids have no idea.

silentC
1st November 2006, 09:38 AM
How do you know when you're an old phart?

When you can remember using a slide rule :p

I was in high school the first year they allowed calculators in the HSC maths exam. Everyone in the class was expected to buy a calculator. Casio fx36 I think. We had a whole subject on how to use one. There was a chapter in the textbook.

One of my mates had his older brother's slide rule. He thought he was clever because he knew how to use it. He wasn't. He was a nerd!! ;)

bennylaird
1st November 2006, 09:44 AM
Is that like remembering Pounds Schillings and pence? The walk down to the back of the yard to the long drop and newspaper rather than a roll. Dripping sandwiches for school lunch. Cream in a bucket from the farm over the road. Being able to leave the door unlocked. A copper giving you a kick in the ar...e rather than booking you when you played up. Petrol needing to be pumped up to the top of the bowser with a hand pump then allowed to run down into the tank. The wonderful smell of the steam train in the station...........etc etc

Wood Borer
1st November 2006, 09:45 AM
You old pharts.:D :D :D

I have four or five or them also including the Faber Castell that I used in Leaving and HSC and Uni before you were allowed to used calculators. There weren't any to use apart from the HP with the Nixi tubes.

echnidna
1st November 2006, 09:56 AM
they make good paint stirrers nowadays

bennylaird
1st November 2006, 09:58 AM
Just so the youngsters know what we are talking about:confused: :confused:

Stuart
1st November 2006, 10:16 AM
Played with one, learnt some basics on it, but calculators were coming..... Still have the table book though, so I sorta fell in the gap between slide rules and calculators. Still remember buying my first calculator - $15 and it could + - / x and square root, and that was about it, oh, and it knew Pi.

bennylaird
1st November 2006, 10:23 AM
3.1415926535897932.................................?

bennylaird
1st November 2006, 10:26 AM
Ask a kid these days to give you the exact answer to the sin of 60 degrees, tell them they are wrong if they give you it from a calculator to only 10 decimal places:( :( :( :(


Only accept an answer of root 3 on 2.:D :D :D

echnidna
1st November 2006, 10:37 AM
and pi is 22/7

bennylaird
1st November 2006, 10:39 AM
Well close but not really:( :D

Stuart
1st November 2006, 10:40 AM
Good movie too

jmk89
1st November 2006, 10:56 AM
I'm with echidna Bob on pi - when I do these sort of calculations I have to take account of the tolerances of my skills in implemeting them - so 22/7 is probably too accurate:D :D :D

bennylaird
1st November 2006, 11:10 AM
3.141 592 653 589 793 238 462 643 383 279 502 884 197 169 399 375 105 820 974 944 592 307 816 406 286 208 998 628 034 825 342 117 067 982 148 086 513 282 306 647 093 844 609 550 582 231 725 359 408 128 481 117 450 284 102 701 938 521 105 559 644 622 948 954 930 381 964 428 810 975 665 933 446 128 475 648 233 786 783 165 271 201 909 1.....

Where 22/7 is 3.1428571428571428571428571428571.........

Just not quiet close enough for my woodworking skills:p :p :p :D

bennylaird
1st November 2006, 11:14 AM
But if I'm doing a really nice circular table I go a bit futher and use......


3.1415926535 8979323846 2643383279 5028841971 6939937510
5820974944 5923078164 0628620899 8628034825 3421170679
8214808651 3282306647 0938446095 5058223172 5359408128
4811174502 8410270193 8521105559 6446229489 5493038196
4428810975 6659334461 2847564823 3786783165 2712019091
4564856692 3460348610 4543266482 1339360726 0249141273
7245870066 0631558817 4881520920 9628292540 9171536436
7892590360 0113305305 4882046652 1384146951 9415116094
3305727036 5759591953 0921861173 8193261179 3105118548
0744623799 6274956735 1885752724 8912279381 8301194912

9833673362 4406566430 8602139494 6395224737 1907021798
6094370277 0539217176 2931767523 8467481846 7669405132
0005681271 4526356082 7785771342 7577896091 7363717872
1468440901 2249534301 4654958537 1050792279 6892589235
4201995611 2129021960 8640344181 5981362977 4771309960
5187072113 4999999837 2978049951 0597317328 1609631859
5024459455 3469083026 4252230825 3344685035 2619311881
7101000313 7838752886 5875332083 8142061717 7669147303
5982534904 2875546873 1159562863 8823537875 9375195778
1857780532 1712268066 1300192787 6611195909 2164201989

3809525720 1065485863 2788659361 5338182796 8230301952
0353018529 6899577362 2599413891 2497217752 8347913151
5574857242 4541506959 5082953311 6861727855 8890750983
8175463746 4939319255 0604009277 0167113900 9848824012
8583616035 6370766010 4710181942 9555961989 4676783744
9448255379 7747268471 0404753464 6208046684 2590694912
9331367702 8989152104 7521620569 6602405803 8150193511
2533824300 3558764024 7496473263 9141992726 0426992279
6782354781 6360093417 2164121992 4586315030 2861829745
5570674983 8505494588 5869269956 9092721079 7509302955

3211653449 8720275596 0236480665 4991198818 3479775356
6369807426 5425278625 5181841757 4672890977 7727938000
8164706001 6145249192 1732172147 7235014144 1973568548
1613611573 5255213347 5741849468 4385233239 0739414333
4547762416 8625189835 6948556209 9219222184 2725502542
5688767179 0494601653 4668049886 2723279178 6085784383
8279679766 8145410095 3883786360 9506800642 2512520511
7392984896 0841284886 2694560424 1965285022 2106611863
0674427862 2039194945 0471237137 8696095636 4371917287
4677646575 7396241389 0865832645 9958133904 7802759009

9465764078 9512694683 9835259570 9825822620 5224894077
2671947826 8482601476 9909026401 3639443745 5305068203
4962524517 4939965143 1429809190 6592509372 2169646151
5709858387 4105978859 5977297549 8930161753 9284681382
6868386894 2774155991 8559252459 5395943104 9972524680
8459872736 4469584865 3836736222 6260991246 0805124388
4390451244 1365497627 8079771569 1435997700 1296160894
4169486855 5848406353 4220722258 2848864815 8456028506
0168427394 5226746767 8895252138 5225499546 6672782398
6456596116 3548862305 7745649803 5593634568 1743241125

1507606947 9451096596 0940252288 7971089314 5669136867
2287489405 6010150330 8617928680 9208747609 1782493858
9009714909 6759852613 6554978189 3129784821 6829989487
2265880485 7564014270 4775551323 7964145152 3746234364
5428584447 9526586782 1051141354 7357395231 1342716610
2135969536 2314429524 8493718711 0145765403 5902799344
0374200731 0578539062 1983874478 0847848968 3321445713
8687519435 0643021845 3191048481 0053706146 8067491927
8191197939 9520614196 6342875444 0643745123 7181921799
9839101591 9561814675 1426912397 4894090718 6494231961

5679452080 9514655022 5231603881 9301420937 6213785595
6638937787 0830390697 9207734672 2182562599 6615014215
0306803844 7734549202 6054146659 2520149744 2850732518
6660021324 3408819071 0486331734 6496514539 0579626856
1005508106 6587969981 6357473638 4052571459 1028970641
4011097120 6280439039 7595156771 5770042033 7869936007
2305587631 7635942187 3125147120 5329281918 2618612586
7321579198 4148488291 6447060957 5270695722 0917567116
7229109816 9091528017 3506712748 5832228718 3520935396
5725121083 5791513698 8209144421 0067510334 6711031412

6711136990 8658516398 3150197016 5151168517 1437657618
3515565088 4909989859 9823873455 2833163550 7647918535
8932261854 8963213293 3089857064 2046752590 7091548141
6549859461 6371802709 8199430992 4488957571 2828905923
2332609729 9712084433 5732654893 8239119325 9746366730
5836041428 1388303203 8249037589 8524374417 0291327656
1809377344 4030707469 2112019130 2033038019 7621101100
4492932151 6084244485 9637669838 9522868478 3123552658
2131449576 8572624334 4189303968 6426243410 7732269780
2807318915 4411010446 8232527162 0105265227 2111660396

6655730925 4711055785 3763466820 6531098965 2691862056
4769312570 5863566201 8558100729 3606598764 8611791045
3348850346 1136576867 5324944166 8039626579 7877185560
8455296541 2665408530 6143444318 5867697514 5661406800
7002378776 5913440171 2749470420 5622305389 9456131407
1127000407 8547332699 3908145466 4645880797 2708266830
6343285878 5698305235 8089330657 5740679545 7163775254
2021149557 6158140025 0126228594 1302164715 5097925923
0990796547 3761255176 5675135751 7829666454 7791745011
2996148903 0463994713 2962107340 4375189573 5961458901

echnidna
1st November 2006, 11:17 AM
And I bet ya clean the edges up with 40 grit

bennylaird
1st November 2006, 11:19 AM
And I bet ya clean the edges up with 40 grit


Yep on a GMC belt sander:D :D :D :D

baxter
1st November 2006, 12:03 PM
Bennylaird, too good:D :D :D

At 11.10am you post the short version, then at 11.14am you post the long version. I thought to myself, "Self...." this guy should be in the shed on such a nice day (at least here):cool: obviously he has nothing better to do.

Then I looked up you profile and realised that we are paying you to do nothing:D :D :D too good.

I will have to look for my Trigonometry Tables. They are probably with my slide rule and I haven't used either of them since I did Maths ! and Maths 2 in the Leaving Certificate all those years ago.

But don't you get strange looks when you add up a list of numbers (probably with the page upside down to you) while a youngone (read restaurant receptionist or similar) struggles with a calculator then you correct them because they hit the wrong keys. :) :)

Wood Borer
1st November 2006, 12:06 PM
It would still look a bit out though wouldn't it Benny:D :D :D :D

Should one allow for the expansion and contraction of the timber?

Your calculations would be a bit out if an electron in the outer shell of an atom near the edge of the table spat out a photon and dropped to a shell closer to the nucleus.:p :p :p :p

bennylaird
1st November 2006, 12:42 PM
Bennylaird, too good:D :D :D

At 11.10am you post the short version, then at 11.14am you post the long version. I thought to myself, "Self...." this guy should be in the shed on such a nice day (at least here):cool: obviously he has nothing better to do.

Then I looked up you profile and realised that we are paying you to do nothing:D :D :D too good.



Have to keep my mind busy, doing powerpoints all day drives me mad. Would prefer to be on the boards:D :D (teaching or woodwork)

bennylaird
1st November 2006, 12:44 PM
It would still look a bit out though wouldn't it Benny:D :D :D :D

Should one allow for the expansion and contraction of the timber?

Your calculations would be a bit out if an electron in the outer shell of an atom near the edge of the table spat out a photon and dropped to a shell closer to the nucleus.:p :p :p :p

I allow for that with a universal constant derived from the square of the hyponenuse with respect to the energy shell of the said electron:p :p

Thought you would catch me out there?:D :D :D

Wood Borer
1st November 2006, 12:50 PM
Damn - it's difficult to catch out someone who is so clued up.

Terry B
1st November 2006, 12:52 PM
Benny
I remember reading recently how many decimals are needed in reality and it was only about 50 places. Pi is the ratio of circumference to radius. If you take the ratio of the smallest length in the universe which is plancks constant to the largest thing in the universe which is -well the size of the universe then only about 50 decimal places are needed.
The rest is just being pedantic:D

javali
1st November 2006, 01:14 PM
Putting the thread back on track. Here are a few, including a big fat Stanley.

I will happily trade shiny new paint stirrers for any of your old unused slide rules. (Mechanical calculator will also be accepted with thanks.)

AlexS
1st November 2006, 01:53 PM
But if I'm doing a really nice circular table I go a bit futher and use......


3.1415926535 8979323846 2643383279 5028841971 6939937510
5820974944 5923078164 0628620899 8628034825 3421170679
8214808651 3282306647 0938446095 5058223172 5359408128
4811174502 8410270193 8521105559 6446229489 5493038196
4428810975 6659334461 2847564823 3786783165 2712019091
4564856692 3460348610 4543266482 1339360726 0249141273
7245870066 0631558817 4881520920 9628292540 9171536436
7892590360 0113305305 4882046652 1384146951 9415116094
3305727036 5759591953 0921861173 8193261179 3105118548
0744623799 6274956735 1885752724 8912279381 8301194912

9833673362 4406566430 8602139494 6395224737 1907021798
6094370277 0539217176 2931767523 8467481846 7669405132
0005681271 4526356082 7785771342 7577896091 7363717872
1468440901 2249534301 4654958537 1050792279 6892589235
4201995611 2129021960 8640344181 5981362977 4771309960
5187072113 4999999837 2978049951 0597317328 1609631859
5024459455 3469083026 4252230825 3344685035 2619311881
7101000313 7838752886 5875332083 8142061717 7669147303
5982534904 2875546873 1159562863 8823537875 9375195778
1857780532 1712268066 1300192787 6611195909 2164201989

3809525720 1065485863 2788659361 5338182796 8230301952
0353018529 6899577362 2599413891 2497217752 8347913151
5574857242 4541506959 5082953311 6861727855 8890750983
8175463746 4939319255 0604009277 0167113900 9848824012
8583616035 6370766010 4710181942 9555961989 4676783744
9448255379 7747268471 0404753464 6208046684 2590694912
9331367702 8989152104 7521620569 6602405803 8150193511
2533824300 3558764024 7496473263 9141992726 0426992279
6782354781 6360093417 2164121992 4586315030 2861829745
5570674983 8505494588 5869269956 9092721079 7509302955

3211653449 8720275596 0236480665 4991198818 3479775356
6369807426 5425278625 5181841757 4672890977 7727938000
8164706001 6145249192 1732172147 7235014144 1973568548
1613611573 5255213347 5741849468 4385233239 0739414333
4547762416 8625189835 6948556209 9219222184 2725502542
5688767179 0494601653 4668049886 2723279178 6085784383
8279679766 8145410095 3883786360 9506800642 2512520511
7392984896 0841284886 2694560424 1965285022 2106611863
0674427862 2039194945 0471237137 8696095636 4371917287
4677646575 7396241389 0865832645 9958133904 7802759009

9465764078 9512694683 9835259570 9825822620 5224894077
2671947826 8482601476 9909026401 3639443745 5305068203
4962524517 4939965143 1429809190 6592509372 2169646151
5709858387 4105978859 5977297549 8930161753 9284681382
6868386894 2774155991 8559252459 5395943104 9972524680
8459872736 4469584865 3836736222 6260991246 0805124388
4390451244 1365497627 8079771569 1435997700 1296160894
4169486855 5848406353 4220722258 2848864815 8456028506
0168427394 5226746767 8895252138 5225499546 6672782398
6456596116 3548862305 7745649803 5593634568 1743241125

1507606947 9451096596 0940252288 7971089314 5669136867
2287489405 6010150330 8617928680 9208747609 1782493858
9009714909 6759852613 6554978189 3129784821 6829989487
2265880485 7564014270 4775551323 7964145152 3746234364
5428584447 9526586782 1051141354 7357395231 1342716610
2135969536 2314429524 8493718711 0145765403 5902799344
0374200731 0578539062 1983874478 0847848968 3321445713
8687519435 0643021845 3191048481 0053706146 8067491927
8191197939 9520614196 6342875444 0643745123 7181921799
9839101591 9561814675 1426912397 4894090718 6494231961

5679452080 9514655022 5231603881 9301420937 6213785595
6638937787 0830390697 9207734672 2182562599 6615014215
0306803844 7734549202 6054146659 2520149744 2850732518
6660021324 3408819071 0486331734 6496514539 0579626856
1005508106 6587969981 6357473638 4052571459 1028970641
4011097120 6280439039 7595156771 5770042033 7869936007
2305587631 7635942187 3125147120 5329281918 2618612586
7321579198 4148488291 6447060957 5270695722 0917567116
7229109816 9091528017 3506712748 5832228718 3520935396
5725121083 5791513698 8209144421 0067510334 6711031412

6711136990 8658516398 3150197016 5151168517 1437657618
3515565088 4909989859 9823873455 2833163550 7647918535
8932261854 8963213293 3089857064 2046752590 7091548141
6549859461 6371802709 8199430992 4488957571 2828905923
2332609729 9712084433 5732654893 8239119325 9746366730
5836041428 1388303203 8249037589 8524374417 0291327656
1809377344 4030707469 2112019130 2033038019 7621101100
4492932151 6084244485 9637669838 9522868478 3123552658
2131449576 8572624334 4189303968 6426243410 7732269780
2807318915 4411010446 8232527162 0105265227 2111660396

6655730925 4711055785 3763466820 6531098965 2691862056
4769312570 5863566201 8558100729 3606598764 8611791045
3348850346 1136576867 5324944166 8039626579 7877185560
8455296541 2665408530 6143444318 5867697514 5661406800
7002378776 5913440171 2749470420 5622305389 9456131407
1127000407 8547332699 3908145466 4645880797 2708266830
6343285878 5698305235 8089330657 5740679545 7163775254
2021149557 6158140025 0126228594 1302164715 5097925923
0990796547 3761255176 5675135751 7829666454 7791745011
2996148903 0463994713 2962107340 4375189573 5961458901

I guess rough enough is good enough.:rolleyes:

Javali, that's a nice collection. I have a Castell from school and a circular one that I bought before an exam at tech when I'd forgotten the Castell.

Used to astound the youngsters at work & uni with the circular one, doing calcs while they were being booked and finishing before them.

They do teach you to ensure the order of magnitude is reasonable.

Skew ChiDAMN!!
1st November 2006, 02:22 PM
I guess rough enough is good enough.:rolleyes:

Now, if only we could convince him to use millimetres instead of cubits, he could get away with dropping a few decimal places. :rolleyes:


Javali, that's a nice collection. I have a Castell from school and a circular one that I bought before an exam at tech when I'd forgotten the Castell.

I'd forgotten about the round ones... I had a 6"er that came with one of my Time-Life subscriptions. 'Twas a fun little gadget, bit hard to put in the pocket though.

I wonder who ended up pinching it? :(

dmolh
1st November 2006, 02:26 PM
I remember them well, I recently found one in a "random" lot I picked up at an auction.

I also remeber having a circular (drum shaped) slide rule that from memory was about 10 times more accurate (ie 3 or 4 decimal places) than the standard straight rules.

I was the first in my High School to use THE CALCULATOR that the school had purchased - it took 4 AA batterys every other day, and was good for 8 red LED segment digits. From memory the school paid approx $400 for the calculator and it must have been approx 1976.

Ashore
1st November 2006, 02:30 PM
Have to agree with you alex on the circular units , only have an old hemmi 251 left now though, and still play with it occasionally , though these days it takes longer each time to remember how to drive it:(

Felder
1st November 2006, 02:33 PM
Ahhh yes.

But can you punch in 55378008 on a slide rule, turn it upside down and giggle like a school girl?

:D

bennylaird
1st November 2006, 03:02 PM
55318008?????:confused: :D

Driver
1st November 2006, 03:02 PM
YA BASTARDS!!!!!!

Why did you have to go and bring up all this ancient old crap? Now I'm not going to be able to rest until I've found my bloody slide rule and my truly ancient paperback set of log tables (circa 1958) which I've had since Form 1 at grammar school.

I know they're somewhere in the house. :confused:

And now I'll have to find the bloody things! :o

YA BASTARDS!!!!!!!:mad:

Felder
1st November 2006, 03:05 PM
55318008?????:confused: :D

Either 5318008 or 55378008 works, depending on the size of the chesticles.

Not your suggestion. :p

rrich
1st November 2006, 04:31 PM
The calculator causes the greatest loss of reasoning in todays students. On a slide rule we would multiply 2 times 2 and get approximately 4. (3.98 to 4.02, but who's counting?) We had a feel for what the calculation should be. We knew when the numbers just weren't right and would go back to check our work to find the mistake.

Today the numbers ore results produced by a calculator or computer are accepted as fact when in many cases they aren't. My sons (both mid 30s)have difficulty KNOWING if their calculations are accurate, close or on another planet. It is a pitty that they never learned how to use a slide rule.

As for using a slide rule, I have a small six inch Pickett that I use frequently. It's only to calculate fuel mileage in the pick up truck. And, recently I had to make a new hairline cursor for the slide rule as the old one just deteriorated. (I've also got the electrical engineers model Pickett but a twelve inches, it's not too convenient to carry in the truck.)

The really funny thing about knowing how to use a slide rule is that my wife will not allow me to go grocery shopping with her. I'll keep a mental total of the things she is purchasing. As we check out, I'll tell her the approximate cost of everything. Adding plus tax and recycle values. I'm usually accurate to within a half of a dollar and she really gets pi$$ed off.

Do any of you old methane gas clouds remember the cartoon of the student trying to divide infinity by zero on a slide rule? :D

Auld Bassoon
1st November 2006, 05:24 PM
Gotta disagree with part of this. They're only as accurate as the numbers punched in. All too often I've read an answer back from a calculator and the ol' grey matter has jumped in saying "that's not right!" because I always run a mental guesstimate first.

:rolleyes:

I must agree here - I always apply the "does this look right" test as well.

Using a slide rule brings back mixed memories: Satisfaction when I got things right (mostly), and pain (when wrapped over the knuckles at school for making a monkey's uncle out of the calculation).

Then again, using a sextant and declination tables isn't all that different, even if fixing the horizon in a F8 was a tad trying, especially when closing on a lee shore :eek: Ready reckoning to the rescue :p

Iain
1st November 2006, 07:12 PM
My slide rule doesn't work any more, the numbers are blurry.
Still remember the Austins logs and antilogs though.

graemet
1st November 2006, 09:24 PM
I used my Hemmi Darmsdardt all through uni, usually got the numbers right, usually got the decimal in the wrong place unless I did the mental ballpark first. The first calculators came out a few years after graduation and a week's pay bought me one that would add, subtract, multiply & divide as long as you didn't want more than 6 decimals. No squares or trig values. Now they give em away with a notepad at seminars!!!
And we lived in a shoebox in the middle of the road and worked 26 hours a day, eight days every week.
Cheers
Graeme

Groggy
1st November 2006, 09:29 PM
I used a slide rule for work up until 1987 when I changed jobs. There was no faster or simpler way to calculate aircraft weight and balance on the fly (pardon the pun).

I keep my fathers A.W.Faber Addiator Darmstadt in my drawer with my old slide rule. No idea why, just cos I can I guess.

China
1st November 2006, 10:07 PM
Sure can remember them after reading this tread I rummaged through the draw and pulled out the old Aristo only one problem can't for the life of me rememeber how to use it

woodsprite
1st November 2006, 10:51 PM
Strewth! I only asked if anyone remembered them! But glad to read all these great posts and even more gladder to hear folk still use the critters. Javali, love your collection - does having so many mean you can use all of them to resolve an equation to umpteen decimal places? You know, use them in series?

Now the talk of logs and ant-logs has got me going - i know I have my very log book from Tech School - remember Technical Schools? or is that going to start a new thread ;) - somewhere. Will have to dig it out, and then remember what to do with it!

A great read:)
Jeff

Honorary Bloke
1st November 2006, 11:06 PM
My slide rule doesn't work any more, the numbers are blurry.

My slide rule (high school physics class) still works, but my brain is blurry and I can't for my life recall how to use it. :D

Wongo
1st November 2006, 11:14 PM
Benny you made a mistake. The number in red shoud be 5 instead of 4. :D

3.1415926535 8979323846 2643383279 5028841971 6939937510
5820974944 5923078164 0628620899 8628034825 3421170679
8214808651 3282306647 0938446095 5058223172 5359408128
4811174502 8410270193 8521105559 6446229489 5493038196
4428810975 6659334461 2847564823 3786783165 2712019091
4564856692 3460348610 4543266482 1339360726 0249141273
7245870066 0631558817 4881520920 9628292540 9171536436
7892590360 0113305305 4882046652 1384146951 9415116094
3305727036 5759591953 0921861173 8193261179 3105118548
0744623799 6274956735 1885752724 8912279381 8301194912

9833673362 4406566430 8602139494 6395224737 1907021798
6094370277 0539217176 2931767523 8467481846 7669405132
0005681271 4526356082 7785771342 7577896091 7363717872
1468440901 2249534301 4654958537 1050792279 6892589235
4201995611 2129021960 8640344181 5981362977 4771309960
5187072113 4999999837 2978049951 0597317328 1609631859
5024459455 3469083026 4252230825 3344685035 2619311881
7101000313 7838752886 5875332083 8142061717 7669147303
5982534904 2875546873 1159562863 8823537875 9375195778
1857780532 1712268066 1300192787 6611195909 2164201989

3809525720 1065485863 2788659361 5338182796 8230301952
0353018529 6899577362 2599413891 2497217752 8347913151
5574857242 4541506959 5082953311 6861727855 8890750983
8175463746 4939319255 0604009277 0167113900 9848824012
8583616035 6370766010 4710181942 9555961989 4676783744
9448255379 7747268471 0404753464 6208046684 2590694912
9331367702 8989152104 7521620569 6602405803 8150193511
2533824300 3558764024 7496473263 9141992726 0426992279
6782354781 6360093417 2164121992 4586315030 2861829745
5570674983 8505494588 5869269956 9092721079 7509302955

3211653449 8720275596 0236480665 4991198818 3479775356
6369807426 5425278625 5181841757 4672890977 7727938000
8164706001 6145249192 1732172147 7235014144 1973568548
1613611573 5255213347 5741849468 4385233239 0739414333
4547762416 8625189835 6948556209 9219222184 2725502542
5688767179 0494601653 4668049886 2723279178 6085784383
8279679766 8145410095 3883786360 9506800642 2512520511
7392984896 0841284886 2694560424 1965285022 2106611863
0674427862 2039194945 0471237137 8696095636 4371917287
4677646575 7396241389 0865832645 9958133904 7802759009

9465764078 9512694683 9835259570 9825822620 5224894077
2671947826 8482601476 9909026401 3639443745 5305068203
4962524517 4939965143 1429809190 6592509372 2169646151
5709858387 4105978859 5977297549 8930161753 9284681382
6868386894 2774155991 8559252459 5395943104 9972524680
8459872736 4469584865 3836736222 6260991246 0805124388
4390451244 1365497627 8079771569 1435997700 1296160894
4169486855 5848406353 4220722258 2848864815 8456028506
0168427394 5226746767 8895252138 5225499546 6672782398
6456596116 3548862305 7745649803 5593634568 1743241125

1507606947 9451096596 0940252288 7971089314 5669136867
2287489405 6010150330 8617928680 9208747609 1782493858
9009714909 6759852613 6554978189 3129784821 6829989487
2265880485 7564014270 4775551323 7964145152 3746234364
5428584447 9526586782 1051141354 7357395231 1342716610
2135969536 2314429524 8493718711 0145765403 5902799344
0374200731 0578539062 1983874478 0847848968 3321445713
8687519435 0643021845 3191048481 0053706146 8067491927
8191197939 9520614196 6342875444 0643745123 7181921799
9839101591 9561814675 1426912397 4894090718 6494231961

5679452080 9514655022 5231603881 9301420937 6213785595
6638937787 0830390697 9207734672 2182562599 6615014215
0306803844 7734549202 6054156659 2520149744 2850732518
6660021324 3408819071 0486331734 6496514539 0579626856
1005508106 6587969981 6357473638 4052571459 1028970641
4011097120 6280439039 7595156771 5770042033 7869936007
2305587631 7635942187 3125147120 5329281918 2618612586
7321579198 4148488291 6447060957 5270695722 0917567116
7229109816 9091528017 3506712748 5832228718 3520935396
5725121083 5791513698 8209144421 0067510334 6711031412

6711136990 8658516398 3150197016 5151168517 1437657618
3515565088 4909989859 9823873455 2833163550 7647918535
8932261854 8963213293 3089857064 2046752590 7091548141
6549859461 6371802709 8199430992 4488957571 2828905923
2332609729 9712084433 5732654893 8239119325 9746366730
5836041428 1388303203 8249037589 8524374417 0291327656
1809377344 4030707469 2112019130 2033038019 7621101100
4492932151 6084244485 9637669838 9522868478 3123552658
2131449576 8572624334 4189303968 6426243410 7732269780
2807318915 4411010446 8232527162 0105265227 2111660396

6655730925 4711055785 3763466820 6531098965 2691862056
4769312570 5863566201 8558100729 3606598764 8611791045
3348850346 1136576867 5324944166 8039626579 7877185560
8455296541 2665408530 6143444318 5867697514 5661406800
7002378776 5913440171 2749470420 5622305389 9456131407
1127000407 8547332699 3908145466 4645880797 2708266830
6343285878 5698305235 8089330657 5740679545 7163775254
2021149557 6158140025 0126228594 1302164715 5097925923
0990796547 3761255176 5675135751 7829666454 7791745011
2996148903 0463994713 2962107340 4375189573 5961458901

bsrlee
2nd November 2006, 02:01 AM
I'm just waiting for one of you to pull out a Babbage engine - I just want an agent's commission when you sell it.

The last (and I believe ONLY) fully working Babbage engine was found in Australia several years ago, in the possion of an elderely lady, whose father had brought it with him to Australia after retiring from the Indian Civil Service - I beleive the LOL got a VERY large sum of money for it at auction.

I know I should express that better, but my brain isn't working too well.....:confused:

echnidna
2nd November 2006, 09:10 AM
How many of you old pharts still have the brown paper bag yer slide rule came in when ya got it?

MurrayD99
2nd November 2006, 09:32 AM
Log tables, trig functions.... SOHCAHTOA. Oh ho. All these have been extremely useful.... Yep, I had a circular slide rule and a nice green and white one that is still around somewhere. Remember the ones made of wood with a melamine(?) surface.

Felder
2nd November 2006, 09:39 AM
Slide Rules;

1. All children must be supervised by an adult.

2. Please ensure that the slide is empty before embarking upon your descent.

3. Swearing will not be tolerated on the slide.

4. You must be this high to ride this slide.

5. Please do not tip water onto this slide.

6. One child at a time - NO TRAINS!

:D

bennylaird
2nd November 2006, 09:53 AM
Bugr your right:eek: :eek: :eek:

Have to start my round table again bugr it:( :( :(



Benny you made a mistake. The number in red shoud be 5 instead of 4. :D

3.1415926535 8979323846 2643383279 5028841971 6939937510
5820974944 5923078164 0628620899 8628034825 3421170679
8214808651 3282306647 0938446095 5058223172 5359408128
4811174502 8410270193 8521105559 6446229489 5493038196
4428810975 6659334461 2847564823 3786783165 2712019091
4564856692 3460348610 4543266482 1339360726 0249141273
7245870066 0631558817 4881520920 9628292540 9171536436
7892590360 0113305305 4882046652 1384146951 9415116094
3305727036 5759591953 0921861173 8193261179 3105118548
0744623799 6274956735 1885752724 8912279381 8301194912

9833673362 4406566430 8602139494 6395224737 1907021798
6094370277 0539217176 2931767523 8467481846 7669405132
0005681271 4526356082 7785771342 7577896091 7363717872
1468440901 2249534301 4654958537 1050792279 6892589235
4201995611 2129021960 8640344181 5981362977 4771309960
5187072113 4999999837 2978049951 0597317328 1609631859
5024459455 3469083026 4252230825 3344685035 2619311881
7101000313 7838752886 5875332083 8142061717 7669147303
5982534904 2875546873 1159562863 8823537875 9375195778
1857780532 1712268066 1300192787 6611195909 2164201989

3809525720 1065485863 2788659361 5338182796 8230301952
0353018529 6899577362 2599413891 2497217752 8347913151
5574857242 4541506959 5082953311 6861727855 8890750983
8175463746 4939319255 0604009277 0167113900 9848824012
8583616035 6370766010 4710181942 9555961989 4676783744
9448255379 7747268471 0404753464 6208046684 2590694912
9331367702 8989152104 7521620569 6602405803 8150193511
2533824300 3558764024 7496473263 9141992726 0426992279
6782354781 6360093417 2164121992 4586315030 2861829745
5570674983 8505494588 5869269956 9092721079 7509302955

3211653449 8720275596 0236480665 4991198818 3479775356
6369807426 5425278625 5181841757 4672890977 7727938000
8164706001 6145249192 1732172147 7235014144 1973568548
1613611573 5255213347 5741849468 4385233239 0739414333
4547762416 8625189835 6948556209 9219222184 2725502542
5688767179 0494601653 4668049886 2723279178 6085784383
8279679766 8145410095 3883786360 9506800642 2512520511
7392984896 0841284886 2694560424 1965285022 2106611863
0674427862 2039194945 0471237137 8696095636 4371917287
4677646575 7396241389 0865832645 9958133904 7802759009

9465764078 9512694683 9835259570 9825822620 5224894077
2671947826 8482601476 9909026401 3639443745 5305068203
4962524517 4939965143 1429809190 6592509372 2169646151
5709858387 4105978859 5977297549 8930161753 9284681382
6868386894 2774155991 8559252459 5395943104 9972524680
8459872736 4469584865 3836736222 6260991246 0805124388
4390451244 1365497627 8079771569 1435997700 1296160894
4169486855 5848406353 4220722258 2848864815 8456028506
0168427394 5226746767 8895252138 5225499546 6672782398
6456596116 3548862305 7745649803 5593634568 1743241125

1507606947 9451096596 0940252288 7971089314 5669136867
2287489405 6010150330 8617928680 9208747609 1782493858
9009714909 6759852613 6554978189 3129784821 6829989487
2265880485 7564014270 4775551323 7964145152 3746234364
5428584447 9526586782 1051141354 7357395231 1342716610
2135969536 2314429524 8493718711 0145765403 5902799344
0374200731 0578539062 1983874478 0847848968 3321445713
8687519435 0643021845 3191048481 0053706146 8067491927
8191197939 9520614196 6342875444 0643745123 7181921799
9839101591 9561814675 1426912397 4894090718 6494231961

5679452080 9514655022 5231603881 9301420937 6213785595
6638937787 0830390697 9207734672 2182562599 6615014215
0306803844 7734549202 6054156659 2520149744 2850732518
6660021324 3408819071 0486331734 6496514539 0579626856
1005508106 6587969981 6357473638 4052571459 1028970641
4011097120 6280439039 7595156771 5770042033 7869936007
2305587631 7635942187 3125147120 5329281918 2618612586
7321579198 4148488291 6447060957 5270695722 0917567116
7229109816 9091528017 3506712748 5832228718 3520935396
5725121083 5791513698 8209144421 0067510334 6711031412

6711136990 8658516398 3150197016 5151168517 1437657618
3515565088 4909989859 9823873455 2833163550 7647918535
8932261854 8963213293 3089857064 2046752590 7091548141
6549859461 6371802709 8199430992 4488957571 2828905923
2332609729 9712084433 5732654893 8239119325 9746366730
5836041428 1388303203 8249037589 8524374417 0291327656
1809377344 4030707469 2112019130 2033038019 7621101100
4492932151 6084244485 9637669838 9522868478 3123552658
2131449576 8572624334 4189303968 6426243410 7732269780
2807318915 4411010446 8232527162 0105265227 2111660396

6655730925 4711055785 3763466820 6531098965 2691862056
4769312570 5863566201 8558100729 3606598764 8611791045
3348850346 1136576867 5324944166 8039626579 7877185560
8455296541 2665408530 6143444318 5867697514 5661406800
7002378776 5913440171 2749470420 5622305389 9456131407
1127000407 8547332699 3908145466 4645880797 2708266830
6343285878 5698305235 8089330657 5740679545 7163775254
2021149557 6158140025 0126228594 1302164715 5097925923
0990796547 3761255176 5675135751 7829666454 7791745011
2996148903 0463994713 2962107340 4375189573 5961458901

pedro the swift
2nd November 2006, 10:09 AM
Slide rules?
Yep, used one years ago doing electrical/electronics stuff. Still got my Nestler Elektro and my Faber-Castell super rule with scales I never mastered.
Found them to be quick and certainly accurate enough for engineering use.
Still pick one up occasionally and have a short refresher for auld lang syne.
I did hear of a contest once where a slide rule operator was pitted against a calculator and the slide rule guy won for speed in doing accurate calcs.
Long Live the rule. No Batteries!

jaspr
2nd November 2006, 10:39 AM
I can't believe there is a long thread on slide rules.

I was cleaning out an old storage box in the workshop last week - to make room for more woodworking. It contained what was left of my life from uni days.

And there it was a slide rule in it's plastic cover - a Hemmi - I had to check. Can't for the life of it remember how to use it - so I couldn't convince my 11 year old son that it had any use at all!

I don't think I used it much. I used printed log tables in high school and then pretty well went on to the first calculators in uni. Someone mentioned buying one for $15 dollars. Not back then! The first one I got just did the 4 basic functions and had a single memory register. It was a plug-in version with an external transformer. It cost about $50 back then, from memory. The screen had big green numbers on it.

Anyone know the Munro Calculating Machine? One of my lecturers (he was a bit of an anachronism, even back then) insisted we use it - for a giggle.

It had a pull handle on it just like a poker machine. You entered some numbers into it, pulled the handle, mechanical things whirred and whizzed, and the answer was printed - I think - onto a roll of paper.

And then there was the university computer ... punched cards ... lodged in batches for the operators to run ... don't get me started!

ok .. I'll finish now.

AlexS
2nd November 2006, 02:19 PM
Anyone know the Munro Calculating Machine? One of my lecturers (he was a bit of an anachronism, even back then) insisted we use it - for a giggle.

It had a pull handle on it just like a poker machine. You entered some numbers into it, pulled the handle, mechanical things whirred and whizzed, and the answer was printed - I think - onto a roll of paper.

And then there was the university computer ... punched cards ... lodged in batches for the operators to run ... don't get me started!

ok .. I'll finish now.
Oh yeah, the Munro. Used one in the army. Sure, they had a printer, but they weren't a patch on the Facits. Key in the multiplicand, crank in the multiplier, the result comes up in a window. For division, turn the crank the other way. But the Rolls Royce of calculators was the Vega, designed during the war by a concentration camp inmate and made by him after the war.

We had another electrical calculator at work - can't remember the brand - that we used to drive almost to self-destruction by dividing 0 into 0. The motor just kept accellerating. It siezed up once, so someone sprayed it with WD40. When they switched it on, there was a flash and a puff of smoke, but the calculator worked.

Iain
2nd November 2006, 04:15 PM
Slightly off topic I have seen the Chinese use the abacus with amazing speed, agility and accuracy, then there are the finger counters which I first thought was a joke until I found out that this ancient art utilise ten fingers and the knuckles represent 10's 100's 1000's etc.
There is a name for it but I cannot recall what it is, but these people performed some amazing calculations utilising what they were born with.

Chris Parks
2nd November 2006, 10:22 PM
That was an interesting book....Slide Rule by Neville Shute when he and Barnes Wallace engineered an air ship. The chapter describing the teams of engineeers doing all the calculations for the air ship structure was amazing. it took them weeks to do it all and if the answer wasn't right they went back to see where the error was and all done with slide rules. Well worth the read.

Ashore
2nd November 2006, 10:41 PM
When they switched it on, there was a flash and a puff of smoke, but the calculator worked.
Not like these days Alex once you let the smoke out the thing is cactus:D

javali
4th November 2006, 03:26 PM
Anyone know the Munro Calculating Machine? One of my lecturers (he was a bit of an anachronism, even back then) insisted we use it - for a giggle.



Some may be wondering what you are talking about...

joe greiner
5th November 2006, 04:09 AM
Yup. Had one almost like that. Partially "repaired" it once. As I recall, under each column of keys was, in effect, a ten-speed transmission.

On some other models (electric), you could set up a division problem so that it "played" a "tune."

JG

Stuka
21st November 2006, 08:07 PM
bennylaird post 15

Very good advice but pick your kid or don't be offended by certain phrases that start with get and end with off.

My initation to slide rules was 1962, tec teacher wouldn't let you into the class room without one (electrical apprenticeship). Found it a few yrs back, couldn't remember how to use it, got sick of shifting it around a draw looking for other stuff so I turfed it. Darn just found out I wasted a good paint stirer.

Can you imagine waiting at the supermarket check-out waiting for the slide rule answer.

Cheers

joe greiner
21st November 2006, 10:09 PM
Phew! I thought this thread would have been exhausted by now. But, OK, I'll do my part to keep it alive.

My slide rule is right next to my mouse. Batteries never go dead. Don't have to press "start" to make it stop.

Several years ago, I made a circular slide rule. Calculated the angles and radii for the ticks in a spreadsheet. Inserted text for AutoCad script. Exported to a script file. Ran the script in AutoCad (fun to watch). Printed two copies. Glued to cardboard. Cut out big circle and small circle. Several coats of 50:50 pva and water. Bolted together with a nylon-insert nut. I kept it by the copy machine at work to assist scaling copies. And, yeah Skew, somebody either pinched it or trashed it. I suppose I could print it again, if only I could find the file. Probably on another computer, though.

Joe

bennylaird
21st November 2006, 10:56 PM
bennylaird post 15

Very good advice but pick your kid or don't be offended by certain phrases that start with get and end with off.


Cheers


Yes had that problem with a girl I tutored, no way was she going to anything but use the calculator. Oh she failed by the way:D :D

root 3 on 2 was not an option

jmk89
23rd November 2006, 04:26 AM
Yes had that problem with a girl I tutored, no way was she going to anything but use the calculator. Oh she failed by the way:D :D

root 3 on 2 was not an option

Benny,

She sounds like the student I tried to help with her maths about 25 years ago. For her every probability was 1/2 - it either happened or it didn't. [I don't know which smily to use - because it is true and funny but really very sad]