Concise Ruler Circular Calculator 27N 100805

The quality of this slide rule is quite nice and it is easily readable. The contrast on the font is quite comfortable to read. I had never used a slide rule before, but the instructions are quite clear and I found it to be accurate and easier to use than I had originally thought it would be. It's kind of fun to use. I highly recommend this product.

This is a relatively standard circular slide roll with the most important scales being c and d on the front and of course the trig functions on the obverse. Everything works. I noted that there were some comments that said it wasn't precise enough. It seems fine to me. I can do three digits for most calculations, whereas for the borderline ones some of them are like 2.5 digits. Everything works fine. It's in good condition and I'm glad somebody still makes real slider rules. If you're not familiar with this particular format. This is roughly equivalent to a 12-in slide rule. The outer scales are a little bit longer and therefore a tiny bit more precise than a 12-in and the inner scales are roughly equivalent to an 8-in wide rule. That of course is because the diameter is what determines the precision. And the diameter changes depending on whether using inner scale or outer scales.

It's a nice little instrument, but doesn't have all of the functions of classic slide rules. It multiplies, divides, finds inverses, does square and cubes, square roots and cube roots, but does not do trig functions or logarithms. It has a handy set of conversion factors on the back side. It's somewhat of a novelty these days, since you can buy an electronic scientific calculator for less, but it would be fun to show to younger folks who never learned to use a slide rule. Made in Japan, but made for the western market, so instructions are in English. This review so far refers specifically to the model number 28n. Several models were shown on the same listing, and not all of them had instructions in English. I also purchased the one labelled No. 480, and the instructions that came with that one were in Japanese. Fortunately, the front side was very similar to a circular slide rule that I purchased in college and I was able to figure out how to use the front side based on those instructions. It did everything that the model 28n did, plus logarithms, but it still did not do trig functions. It has a larger diameter than the 28n, which makes it somewhat easier to read. The back side was a long term calendar from 1926 to 2043. It also shows the corresponding years of the three most recent Japanese eras (Showa, Heisei, and Reiwa). I was able to figure out a lot by observation, but, again, the instructions are in Japanese.

I love, love my slide. It has a good alignment, easy to read and a very nice size. I have smaller ones, but this one is a palm or slightly larger than my hand and that makes it easier to read the markers. I know that people don't use slide rules anymore, but I use them when I was in high school and in college. They are magic. I think that they help me use my brain more. When I told my colleagues in the math department, I taught chemistry, that I'm using a slide role instead of a calculator to work on trigonometry problems on my own, they fell all over me to learn how to use a slide roll. It's an amazing tool. The slide rule really does help me stop and think about the answer to my problems that I'm solving with math so I'm not just plugging in a number and saying ;'well the computer said it was this answer.', I'm actually asking myself. Is it the right answer?

This is a very well engineered slide rule that fits into your shirt pocket. The movement is smooth and the scales and characters are easy to read. Electronic calculators are ubiquitous, but I enjoy using a slide rule because I feel it exercises my mind a bit more. Using a slide rule you gain a better sense of magnitude and a keener ability to approximate accurately. While technology has made our lives easier it has also made us lazy and mentally “flabby”. Superseded technologies can often exercise long dormant mental potential. Highly recommended.

The slide rule is brand new and well made. The instructions are in Japanese, but English versions are available by searching slide rule history sites. The scales are all standard, so any decent slide rule manual will provide needed how-to information.

The Concise 300 is a seriously capable 4" circular duplex slide rule. Scales on the front are K, A, D, C, CI, B, and L. On the reverse are LL1, LL2, LL3,D, C, S, T1, T2, and ST scales. Scales are engraved, clear and well aligned. The central slide rings on both sides move smoothly, as does the cursor. I have tested its most basic scales and found them quite accurate, well aligned and easy to read. I'm not yet familiar with all the scales on this model but have no reason to doubt they are equally well executed. The construction is sturdy and should be durable. My one complaint is the instructions are only in Japanese. I was able to download a set of instructions in English from a third party site. Failure to include them with the rule as shipped is a deficiency because the Concise circular rule operates differently from others like the older Picketts, and has different scales arrangements that require some significant changes in how the rule is manipulated The size of the 300 makes it too large for most shirt pockets. But, it will fit in most larger jacket or suit pockets. Aside from the issue with the instructions, the Concise 300 is a very satisfactory tool, easy to set and read with good precision, well made and darned convenient.

very readable double sided instrument. Like the LL scales Instructions completely in Japanese but not a problem for an experienced user, glad someone is making sliderules still. They are superior to electronic calculators in many ways. Being circular never any need to reset index.

Having a slide rule watch which is giving up the ghost, I didn’t want to let my knowledge of using them go to waste. So I decided to buy this gadget, ( being the nerd that I am) for calculating on the fly. It’s very handy for conversions and ratios, and, unlike my watch, as an inverse scale too. This allows you to calculate, for example, the kind of problem such as; if it takes 20 men 70 days to build a house, how long would it take 17, 40 or 28 men? The only gripes I have are that it is a tad tinier than I expected and, depending on how dry my hands are, can be a little tricky to rotate the central dial.

計算尺は良い物でございます。 今後も生産し、いつでも買うのが出来ったら欲しいですね……。

Me gusta que no requiere baterías y los usos en cálculos solo muy amplios

Há muito tempo estava procurando por uma régua de cálculo circular. É uma obra de arte da engenharia! É pena que ninguém mais aprenda a manuseá-lo na faculdade.