I am an avid Vacumatic OS and Maxima collector, but far from being an expert. I usually differentiate an OS or Max by the length of the pen, diameter of the cap, and the larger nib (I.e 9 or 10 feather nib etching as opposed to the 7 or 8 feather). I was cleaning out a Brown OS and discovered that it has a 7-feather etching, but is the same size as the usual OS and Max Nibs. The pen has a made in USA print with a 45 date.
Have I been wrong with one of my criterias? Is this just an anomaly with bad Parker QC? I have also come across nibs with 8-feathers on one side of the shaft and 9-feathers on the other.
Any help would be appreciated.
I believe that the nib is formidable and corresponds to an oversize; this size nib would be "loose" in the feed of any other non oversize and, in effect, 4th quarter of 1936 (and in my opinion, more specifically, November 1936; .46.(2 dots)=October, 46. (1dot)=November and 46 (whitout dot)= December) There are not 3 dots when the system had two figures,
In 1936 the catalogued OVERSIZE was 133/135 mm length and 15 mm diameter, however considering the diversity of off-catalog lengths, nibs and feeds of the early years, perhaps the most accurate measurement to know the largest sizes in vacumatic models would be the diameter in cap band or rings very close to 15 mm. (the "full length" -we could say- non oversized have 14 mm diameter)
On the other hand, in general, would be necessary a greater concretion about "Maxima" as oversize because pens of "Maxima" name only was the biggest size from 1941onwards, so:
1934-35 the biggest was named OVERSIZE model 15 mm diam. +- in rings cap (followed by Standard with smaller diameter and shorter length).
1936 the biggest was named OVERSIZE model (followed by Senior with smaller diameter and wider central ring).
1937-38 (new streamlined shape) the biggest was named SENIOR MAXIMA model (followed by Maxima with smaller diameter).
1939-1940 (already incorporated Blue Diamond) the biggest was named SENIOR MAXIMA model (followed by Slender Maxima with smaller diameter)
1941 the biggest was named MAXIMA (followed by Major)
We usually leave the expression "button filler" for push buttons in pen with sac. In this particular case we usually talk about the vacumatic system and in your pen of 1st generation, prior to the streamlined line, we usually speak of a vacumatic "lockdown" that's what Parkers called them.
Edited by RamonCampos, 28 December 2018 - 20:14.