Sun Hemmi

Sun Hemmi 153

A lovely high end rule with several unusual scales for trig and hyperbolic calculations.

I like that the original owner, C. Wrightson, had his classily engraved. I can see why he would not have wanted to lose it!

Sun Hemmi 130

Another nice Sun rule, rather like my Diwa in feel. The cursor wraps over the bottom edge for the trig scales.

Sun Hemmi 130W

This rule boasts 5 log log scales on the back of the slide. On the front it has a BI for dividing by squares and a P (power) scale. There's a lot of useful stuff on the back, but alas, the only way I can read it is with a magnifying glass (or the image below viewed at full size).

It and the 130 above are hefty "desktop" models. One practically feels armed with one in his hands.

Sun Hemmi 45K

This is a very pretty, simple rule in a compact 9 inches (8" scale).

An interesting glyph on the back shows that if you flip the slide over, then given sides a and b or a and c of a triangle, you can easily find the angle opposite a.

Sun Hemmi P280

This is a plastic rule that screams "student". The slide has log scales on the reverse, so you can calculate powers if you flip it over. But it doesn't seem like a very convenient design.

Sun Hemmi 30 (1930-WW2)

At 4" (10cm) this little guy is about as small as you can make a linear rule and still have it be legible - barely! They made an identical rule with a magnifier, the model 32. Sun made the same rule for a variety of companies, including Post in the USA, and Hughes-Owens in Canada.

Sun Hemmi Instruction Book

This is a nice manual with lots of clear instructions and diagrams teaching how to solve problems on each different kind of Hemmi. A large appendix tries to help match you up with the Hemmi that best serves your needs. It catalogs the scales you need to solve various problems, and cross-references which Hemmis have those scales. There are also diagrams of all the Hemmis, and a table of the scales on each.

The material has a copyright of 1955, but the back cover indicates a print-date of December 1956.