Nestler 0231 Holzhändler timber trader slide rule 1959 Germany

This is a very interesting model for timber traders, a Rietz model with extra’s! It can be recognized by the 3 red symbols on an otherwise very simple lay-out model. It is the successor to the model 31 Holzhänlder (made until the early 1920’s in Mahogany) and have seen some redesigning as well. I can only find references to this model as being produced for over a decade in the 1950’s-1960′ in wood. Yet this model is date stamped 1959 and made in Aganit (plastic compound name used by Nestler), which probably shows not many have been in real life. It comes with a Rietz / Darmstadt standard manual, plastic sleeve and outer box. It looks te me like Nestler was decommissioning this rule by marketing it as a Rietz model…all very interesting. The red symbols were discussed in the 31 manual though, where the left and right arrow symbols (formerly known as U) are for the Umfang / circumference of the tree and the middle red symbol for the diameter. Other marking becomes obsolete or incorporated in the multi hairline (3x red, 1 black) cursor. Slide rule, sleeve, manual and cursor are in great condition the box is missing the side and shows clear signs of storage. The rule measures 29,5 cm or 11 3/4 inches wide. Check the attached video on how to work your vintage man tool : slide rule operation instructions!