Hi, Matt.
Yes, the vent cover was, as Dave says, to keep cinders (and rain and snow) from dropping into the opening from the sliding hatch cover.
I don't know if all of the hatch covers always slid, or if they were changed when the sheet iron covers you are asking about were added.
The covers began to appear in 1950, and by 1953, almost all of the K-36's and K-37's had them.
There were exceptions. #484 comes to mind as never having had the vent cover. If it has a hinged vent cover, I'd guess that these were changed when the covers were put on.
There were also some variations. #483 had a shorter profile cover, and it was straight at the ends, if I recall correctly.
In 1986, I measured the one on #487 for an Overland Models project. I can't get to that at the moment, but I have also measured the one on #491 for a project of my own.
#491's, which appears to me to be most typical, is 27" wide, the flat top measures 36" long. the angled ends are each 12" with about a 2" flange that mates to the roof. The height of the cover at the sides over the roof is 10". I believe #487's cover is 24" wide. The center of the cover is supported by formed strap iron, it is not square, it is flat and about 2" wide. It is possible that some of them could be formed using angle stock, but they are not square.
I have made several of these (in On3), and I usually use a piece of thin brass stock cut 27" wide and 5' 6" long.
You or anyone interested can contact me for more information, but I think I've covered your basic questions here. The rest is probably "model specific". They have only been rarely done properly on brass imports.
Mike Trent
mike_trent_476@hotmail.com
Edited 1 time(s). Last edit at 09/17/2009 04:39PM by Mike Trent.
