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Wed. J. Ahrend & Zoon: Electro 15

Wed. J. Ahrend & Zoon Electro 15 Electro

Details of: Wed. J. Ahrend & Zoon - Electro 15

Type? Usually a generic name preceded by the form if not standard linear length - e.g. Pocket Enhanced Mannheim. For special models often supplemented by its function/use - e.g. meteorology. Sometimes a suffix is needed to distinguish between different versions - e.g. early or late. Electro
Sort? L/C/D/T/W/X where L=Linear, C=circular, D=Drum, T=tubular, W=watch, X=miscellaneous (i.e. the rest) L
Construction? Basic construction form of the body i.e. Closed/solid frame or Open frame or Duplex or Other Closed/solid frame
Material? Basic description: ivory/bone/wood/bakelite/plastic/metal/cardboard or combinations e.g. wood/veneered, wood/painted, etc wood/celluloid veneers
Length? Mostly length in cm or ” (inches) of the D scale but excluding any scale extensions. But for circular or watch slide rules it is the diameter & for tubular or drum slide rules it is the overall linear scale length. For other mechanical aids it is the physical length. 25cm
Scales front? Standard (not maker’s) symbols for scales on front face e.g. A = X² (1-100) but § = generic symbol for any non-standard scale. Scales between solidi (/ /) are on the slide(s) whereas a vertical line ( | ) or reversed solidus ( \ ) + a symbol denotes scale(s) on a straight or bevelled side edge. cm \ LL2,A / B,C / D,LL3 | inch
Scales back? Standard (not maker’s) symbols for scales on back face e.g. S = sine (5° to 90° & 85° to 0°) or sin(x) but § = generic symbol for any non-standard scale. Scales between solidi (/ /) are on the back of the slide(s). / S,L,T /
Cursor type? Basic description (incl. material) + no. of hairlines, etc on any cursor(s) or alternative to a cursor - e.g. a stylus metal/glass - 3 hairlines
Condition? Cn where n = 0-6 based on Herman van Herwijnen’s condition/quality scale C3
Date? YYYY for year(s) of production or an approximation/range of years 1930s
Extras? Basic description of any accessories - e.g. case or stand + where relevant, an accreditation for image, etc black linen covered stiff carboard case with A.W.Faber box mark
Instructions? Details like “on back of rule” and/or language of instruction sheet/booklet - generic or instructions for common layouts usually not listed
Comments ? Any special or noteworthy traits + significant use-related facts + pertinent details of scales/tables in well of stock + any significant tables, etc on the back of the stock

OEM version made by KHH (5 slits in well + 5 adjustment screws on botton side edge) but often mistaken as Dennert & Pape because of model no. - V & W scales in well of stock + conversion tables (in NL) on back - see also identical model sold by OHICO & Kahn

In-Out? MM-YYYY / MM-YYYY of the date added/left the collection or <YYYY if exact MM-YYYY no longer known <2010/

All of:  Wed. J. Ahrend & Zoon new search?

ModelType
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