I have just finished sorting my collection of control blacks of the Army Post Stamps and it occurs to me that there may be some control block addicts (like myself) who would find some interest m a list of the differences between the controls on the two panes of these issues.
The Large Stamps
3 mill control A/36
Pane A - overall width of control 9.5 mm Length of stroke 6.7 mm there s a faint "dribble" of colour from the left leg of A.
Pane B - overall width of control 9.0 mm. Length of stroke 6.5 mm.
10 mill control A/36
Pane A -roll width of control 9.5 mm. Length of stroke 7.0 m
Pane B - overall width of control 9.1 mm. Length of stroke 6.2 mm.
Pane A - roll width of control 9.0 An. Length of stroke 6.0 mm
Pane B - overall width 0f control 9.5 mm. Length of stroke 7.0 mm.
controls A/38:A/39 and A/38W39:B/39
Pane A - the lower of the two bars across A/38 is much larger than the upper and extends about 3.0 mm. to the left.
Pane B - both bars are the same length.
The Small Stamps
It is easy to identify the two panes from their perforations. The pane which I have christened Pane A has the perforations extending across the bottom margin.
Pane B has the perforations across the right hand margin.