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Maybe a fox

Is it a badger

What do you like more infrared or night vision if price wasn't a problem?

Excellent video. Just started getting into these. Deci-lon is also one of my favorites.

I would NEVER buy any slide rule with 'conversions' on the back made before 1960! Do you know why? 1960 was IGY == International Geophysical Year. Example: 1" now == 2.54 cm EXACTLY; not so before 1960 -- before then that, conversion was some other number. How IGY might creep into calculations, I'm not certain -- but I would not trust them!

It makes math fun again 😊

I recently found my Dad's slide rule. A Dietzgen maniphase 1732. I had started to learn how to use a slide rule in high school in 1972. Then calculators came out and that was the end of the slide rule. I have been learning how to use it and it has given me a real sense of the numbers, as you stated. I'm a civil/structural engineer and I agree that this should be taught in school.

You still see armadillos in you cam?

Have the 23/R

Regarding 5:43, there is an alternate method to calculate 4^3.5 on the Darmstadt slide rule as follows: On the back side of the slide rule, move the slide to the left such that the 4 on the e^x scale is under the left index hairline. Flip over to the front side of the slide rule. Move the cursor to 3.5 on the D scale and read on the C scale that its number is 4.85. Next move the slide to the left such that 4.85 on the C scale is now over 1 on the D scale. Flip over to the back side and read under the left index hairline that the answer is 128. In summary, these operational steps performed: 4^3.5 = e^4.85 = 128.

Regarding 5:08, as an alternative to using the exponential scales while they are on the back side of the Darmstadt slide rule and having to flip it from back to front and back again. The slide itself can be reinserted to the front of the slide rule such that the exponential scales are now completely visible on the front. Doing so eliminates the need to flip the slide rule back to front and back again.

My father bought one of these in the early 1960s for college (in its Frederick Post incarnation, which seems to have been called a Post 1491), since he was studying chemical engineering for a while, and I spent some time playing with it as a kid. I think he has it now. I remember being puzzled by its scales and, of course, it was hard to look up how to use the ones on the back because they were pretty much unique to this model. The most unusual thing about it for a rule this fancy is that on the front, it has a set of log-log scales but no trigonometric scales--not even the ones that exist on basic slide rules. I guess chemists have to raise things to powers a lot but not do a lot of trig.

🐿

Sorry my friend, that ain't no skunk or a KY armadillo, it's a opossum 😂

Esto si me interesa doctor.... buscaré y la desempolvarse mi regla de cálculo.....

I was in the last cadre (I suppose) who learned the slide rule in high school. I never lost my fascination and today have a collection of about forty rules. I recently gave a nice duplex to a friend with two PhDs who had never seen a slide rule, with an instruction book. Your Deci-Lon video is excellent. I also have the Deci-Point, which tracks the decimal point. I'm not very skilled and need to use the instructions to get anywhere. Are you able to expand on the use of this intriguing slide rule?

i have one of these but its missing the cursor for the angles sad i wont be able to use it for that

It's jumping not flying

That slide rule it's made out of Bamboo, very cool. I'm glade you got one. thanks for sharing.👍

Our daughter just picked up a sliderule at ValueVillage this week!! She had no idea what it was! When she brought it home hubby showed her how to use it as i had forgotten how!!

It's a calculator, but it's made out of bamboo!

WOW. Think, this is the model that my great-uncle used when he was an engineer. "Inherited" it as a child, but never learned to use it.

This is a great assistance to my recent research, thank you. Do you know of a book or textbook on slide rules; seems to be almost impossible to find. Im an engineer so looking for dec & log but its becoming a lost art the old slide rule

This is way off topic, but the videos about slide rules remind me of an incidence from my past. In 1956, I started college in an electrical engineering program. After the first night's homework, it was clear that I had a problem. It took hours to do all the needed arithmetic. The next morning, I asked some classmates about the homework and they all said it was trivial. They had all attended special science high schools and knew about slide rules. I had never heard of a slide rule. I obviously needed to buy one and learn how to use it. They all suggested a Kuffell and Esser log log decitrig, which cost about $75, which was way outside my means at the time. It was going to take me a few months to save up enough money for that. But there was available a cheap (75 cents) wooden slide rule, which I could easily afford, and which I bought. Kids can be cruel. I got a lot of teasing about my junky slide rule. One classmate was particularly persistent. After a few weeks of it, I had had enough. So I said to him, "I can get more accuracy from my slide rule than you can get from yours. Let's have a contest." Another classmate would give us randomly chosen 3 digit numbers ( from a telephone directory). My tormenter was to use his slide rule and give as accurate an answer as he could, usually to 4 decimal places, sometimes only three. I would then give my answer, which was always one or sometimes two decimal places more accurate than his. After a few rounds of this, he never figured out how I could possible be getting more accurate answers from my obviously inferior slide rule. What I was doing was using the slide rule to multiply two digit numbers, the two least significant digits of the random numbers, then getting the last two digit of the product my multiplying the training least significant digits in my head, reducing the product modulo 10, and finally stitching the last three significant digits into the three most significant digits of his answer. He never figured it out, but he never teased me again.

Thanks for the video. It was very interesting and good to know about the slide ruler that i have at home. Furthermore thank god, I don’t need to master it. Thanks to a modern calculator!

I own a Hemmi No. 259D "Expert Mechanical Engineer".

I have the same exact slide rule at home.

I won that Deci-Lon in a high school science contest in the very early 1970's. I used it in college. Majored in Mechanical Engineering.

Just a small comment. Koroliev and von Brown used nestler 37 electro. A bit different than dramstad. Nestler wooden slide rule are still very nice to use because they are made from Mahony wood which was cut in early, mid XIX century. So it is pretty well seasoned and therefore stable.

Thank you so much!

Thank you for your video @ 5:40 showing how to find the Area of a Circle given its Radius. If you set 1 on the CF Scale under 8.56 on the DF Scale, then you can perform multiplication such as for finding the Volume of a Cylinder which is the Area of the Circle multiplied by its Height. For example, 8.56 x 2 = 17.1 is the Volume of a Cylinder with a Height of 2. And so forth for finding the Volume of a Cylinder for any other Height.

Thank you for your video. Regarding 2:35, the remedy for plastic slide rules that tend to stick is to apply a few droplets of silicone oil as a lubricant into the groove and the tenon of the sliding contact surfaces. Silicone oil is safe to use on plastic, because silicone lubricant does not deteriorate the plastic. Other people may prefer to use a small amount of PTFE (Teflon) dry lubricant. On the other hand, it is not recommended to use petroleum distillates on plastic slide rules.

I can see these as EXTREMELY useful today, having taken Chemistry.

I’ve been working my way through the instruction manual for my Dad’s Dietzgen Multiplex Dec Trig Log Log slide rule (circa 1950) which I inherited. A lot more fun than I thought it would be, ingenious really. I found the manual online. I saw one of those Decilon slide rules with leather case for $35 plus shipping on Facebook marketplace. I was very tempted.

Debería traducir en español

Is this the 68-1100 model?? Very helpful video. I’m enjoying all your slide rule videos; much appreciation for posting.

Excellent video!! And wow, do I have a lot to learn-especially developing a mental dexterity for powers. I’m getting fairly decent with my slide rules but these techniques make it very powerful. And I love (love!) how using it dramatically improves one’s understanding of math.

That order of magnitude calculation method is brilliant. I have never seen that before. Just got myself a slide rule, so I am studying up on how to use it. Thank you.

I just wanted to take a moment and thank you. It is wonderful that you took the time to make this video

I have a 'pi' on the logscale itself, and an 'e'; but what does 'c' mean??

Can you tell me how a Gilson/Atlas spiral slide rule works? I can multiply and divide with just the D scale, but I don't understand how the spiral C scale works. I saw a site that did mention it, but it wasn't detailed enough.

I've got the same DeciLon you're using in this video, and I'm finally learning how to use it. This is the best order of magnitude explanation I've come across so far! Thanks!

I'd like to find one of these to purchase.

Nice videos! Learning the slide-rule is my thanksgiving vacation diversion but I wasn't thinking it would be this fun. I was having issues with the cube-roots but, while you were working the square-root, I realized how I was messing it up.

btw it can also convert PS (essentially horsepower) to kilowatts and diameter to crossectional area. so if you ask if that 0.5mm in diameter wire is the 2mm^2 wire you are looking for it can do that on a dedicated scale

AVENDRE: J'ai 140 règles de calcul tout neuf N°57/88-Reitz-N-Etudiant & N°57/89-ETUDIANT LOG LOG.Fabrication allemagne en 1965.

AVENDRE: J'ai 140 règles de calcul tout neuf N°57/88-Reitz-N-Etudiant & N°57/89-ETUDIANT LOG LOG.Fabrication allemagne en 1965.

Just use the D and DI scales for reciprocals. The scales are adjacent and on the same side of the rule. No flipping and more accurate.Try it. Find 5 on DI. Note it isadjacent to 2 or .20 on the D scale.

Good video from a man who knows the POWER of the left hand.😎

Regarding 2:24 Keuffel and Esser’s Deci-Lon slide rules were not made from PVC plastic (Polyvinyl Chloride). Instead they were made from Ivorite which is Acrylonitrile Butadiene Styrene (ABS) plastic also known by its brand name Cycolac.