Robert S. Butler posted:
The KB over BW logo dates from the 1930's takeover of Bing by Karl Bub. I don't know how long that combined logo lasted. The actual year for the logo transition was 1933 - according to Claude Jeanmarie's book Bing Modellbahnen.
Yes, there was something major that happened in 1933 in that region, If not mistaken Bing (family) were of Jewish ancestory and the company was removed from his control at that time. I should caution my comments are based on memory of things read over time. That said If I remember correctly Bing then left and went to UK as he had ties with BS and other makers in the UK. Fred or another regional member can probably provide some more accurate detail. Also if you can find Bing and or KBN catalogs from the time there is overlap. A lot of the Bing cars and accesories ended up in KBN catalogs. I have some saved scans of I think a 1932 KBN cat so there may have been some overlap there. But I think Bing was gone from Germany in1933 or soon there after.
Edit, just looked the 1932 is still Bing, not KBN. it is the 1934 KBN scan that seems to show a lot of Bing stuff. Of course timeline wise this would support the 1933 change as discussed above.