While identical in construction to the Ve-Po-Ad, the Sumaster (along with the Fingertip, the Addex and the NuAd) were made in Kansas City, USA while the Ve-Po-Ad (and the Midget) were manufactured in Chicago. Also, the Kansas City adders were often sold as part of an accounting system (with accounting journals and ledgers suitable for a small cash based business). All of these adders (along with the Sum-Fix, the Multi-Sum and the Pocket Adding Machines are derived from the ProCalculo! A key question is: Were they licensed by Meuter or were they 'knock-offs'?
Hello, i added your text to article. Please feel free to modify all that i wrote. Just a little question: was Sum=Fix made in Kansas City too?
For that concern patents, I can just read Patented in Sum=Fix front side. :-(
Do you know anything about Black&Decker production of "Vest Pocket Adding Machines"? See references in Ve-Po-Ad Adder article. Celli 20:04, 17. Ago 2009 (IST)
@celli; I have no information about the Sum-fix (or the Multi-Sum), other than the similarity to the Ve-Po-Ad. I have not seen any instruction sheets, boxes, or other ephemeral, so I have to plead ignorance.
I called the Black & Decker headquarters a few months ago to see if I could get more information about this adder but after being transferred around a few times with no success, I gave up. Whatever the design of the adder, it is obvious that they did not produce a lot of them themselves since B&D moved rapidly into the small electric tool business. It is entirely possible that they sold the design to someone else, although, that is complete speculation.