Early Frappant Conus calculator Machine time slide rule 1910 Germany

This smaller wooden based slide rule is an early model (ca. 1910) by Frappant from Germany, called the Konusrechner. It is singled sided and gives the angles for turning a conus shaped item like a table leg. The cursor hand and the brown scales are both made of iron. It comes in the original wooden case which still holds the original instructions in German. It has clear signs signs of age and use but is still perfectly readable. The back of the case was split since there were no hinges but it is kept together with tape over the back (has new black tape on it now). Also the box is a little deformed but it did and does it’s work perfectly in keeping the calculator safe. It measures ca 15 cm or 6 inches high. Also check out the similar Michaels slide rule. Check the video on how to work your vintage man tool : slide rule operation instructions!