Collection of pages from K&E catalogs for the Deci-Lon Family of Slide Rules


Catalog pages from the 1967 catalog

The Deci-Lon family of slide rules are duplex type of slide rules. The Deci-Lons were constructed on a plastic frame. The Deci-Lon was the last new slide rule design by K&E. The Deci-Lon functionally replaced the Log Log Duplex Decitrig slide rules but never displaced them from the product line. The Deci-Lon has the most extensive scale set of any K&E slide rule.

The scale set is as follows:

The following models are part of the Deci-Lon family and only vary in length:


The Deci-Lons first appeared in the 1962 catalog. The Deci-Lon family last appeared in the 1972 catalog. The following is a brief history of the Deci-Lon family of slide rules as is told in the K&E catalogs that are available at this time. Exact timing is not possible because of the time between catalogs.

These are the known variants of the Deci-Lon 10:

  1. Early production had green leather cases.
  2. Aluminum inserts were place in the end blocks.
  3. The metal frame of the cursor shape was changed for better alignment.
  4. Sometime after 1970 the colored vertical marks on the end of the slider were removed.

Links to catalog pages for the Deci-Lon family of slide rules:

Scans: Link to scans of Decilons