It appears that was the end of the series by WKW. However note that Kalmbach published and sold a couple of books by Walthers including "Simplified Trackwork for Model Railroad Builders" and "Signal and Control Manual for Miniature Railways." On top of that Walthers himself was writing and publishing books on basic modeling issues such as a basic Handbook. WKW also advertised that his personal advice was free to any person who purchased one of his books!
Quite possibly the success of MR (note the article in the August 1934 issue: "Our Circulation Crosses 1000") and the growth of model railroad businesses made Walthers too busy with his model railroad business to contribute more on a regular basis, or perhaps Kalmbach felt uneasy having a paying advertiser also be nearly part of the staff (although there were others in the business who wrote in the early years). There were also articles by "Scenic Sam" and "The Model Nut" and who knows if that was WKW or not. Besides within the year 1934 Linn Westcott came on board and starting writing stuff, often on the same topics that WKW wrote on.
Dave Nelson
I was recently reading the first few issues of MR. In those first 3 issues were a story called Building a Model Railroad. After March or April I can find no reference to the continuation of this story (by Wm Walthers). Was the story ever completed or was it dropped due to lack of reader interest?
Also a bit of irony from Mar 1934/yesterday. I interupted my wife's reading of a book to read her "I've a model husband".