I've always thought myself very fortunate (or, just not clumsy) when I read everyone's "I was changing lenses with one hand, above a ravine above a river, and..." kind of stories. I'm pretty careful with how I treat my equipment and have never had a topple or tumble to report, until today. Not a big one, just a tipping over of a not-fully-extended tripod that I placed on an unseen rock in long grass, as my dog ran by. Luckily the whole lot just tipped over onto long grass and soft dirt, so a fairly cushioned blow. The only casualty, was the screw that locks the shift on the front standard.
From what I can see, it looks like it has two sized threads, a smaller one (probably a reverse thread) that goes into the standard, then it tapers to a larger one which the thumb-screw runs on to lock it all in place.
Well, it's snapped clean through, so I'm trying to chase down anyone who might have any parts from one of these metal field cameras lying around? Willing to pay, of course.