The Sniper's nest ergonomics.

[John Mytton]

Thanks John, here are two views from my mock-up to compare with Powell's and Dillard's photos with:





I am not a photographic expert. However, it appears to me that Powell must have been very close to the corner of the county records building. The location on Roberdeau's map might be off a little, or I am looking at things wrong.

 

Thanks Charles, I missed your post the first time round. Your 3D model proves that the rolling readers box was angled down Elm street and the boxes behind were never moved.

JohnM

[Charles Collins]

Thanks Charles, I missed your post the first time round. Your 3D model proves that the rolling readers box was angled down Elm street and the boxes behind were never moved.

JohnM

You’re welcome John. Creating the mock up was a lot of tedious work. But definitely worth while. Now, if I just had the knowledge and tools to turn it into something that would work with the virtual reality head mounted displays, etc. That would be very useful.

[Charles Collins]

In my now-revised model, I have the west pipe on the line that runs out from the edge of the masonry opening. This is based on a new method of photo-matching I am experimenting with. I have not received measurements from the Museum which will remove all doubt.

My distance from the masonry opening to the west wall is 32". Yours is probably different based on how the model was built. Measurement for the east pipe go to the pipe, not the coupling on the floor.

In an earlier version of this, I incorrectly placed the line on the floor at a right angle to the floorboards.

Thanks Jerry. I like the spirit of cooperation we have on this stuff. By the way, I think that the wall you labeled as the west wall is actually the east wall. For what it is worth, I measured the hardwood floor boards in our house and they are 3-1/4” wide. Also, the pipes appear to me to be electrical conduit. I looked up the standard dimensions for 1-1/2” rigid steel conduit. The outside diameter is 1.9.”

[Denis Pointing]

Thanks Jerry. I like the spirit of cooperation we have on this stuff. By the way, I think that the wall you labeled as the west wall is actually the east wall. For what it is worth, I measured the hardwood floor boards in our house and they are 3-1/4” wide. Also, the pipes appear to me to be electrical conduit. I looked up the standard dimensions for 1-1/2” rigid steel conduit. The outside diameter is 1.9.”

Charles, it's no good measuring the floorboards in your house, the flooring in the TSBD is industrial, not domestic. Also, those pipes are definitely not conduit. I really don't understand why you guys are still struggling with this. You have the best standard measurement possible in the photo. As I posted earlier, 3no vertical courses of bricks plus cement bed is between 8''-8.5''. Now all you need to do is measure the 3no courses on your monitors with a small compass set and all the other measurements, floorboards, pipes etc, all fall into place. I've not done it myself but I'd be very surprised if the flooring isn't approx 6'' and the pipes 4''. 

PS If you try this don't forget the first course of bricks is only half visible. Measure the three above. Good luck.

[Jerry Organ]

The vertical ruler on the bricks in the photo is on an angle to the camera (see upper-left inset). The photographer (the photo was taken on the 25th) appears to be looking down at a sharp angle. However, this would not affect much the inset ruler on the floor.

"Box D" is another way to approximate a sense of dimension. The box as discovered was resting on its top, so fingerprints were partially on the box's bottom. The box was opened from underneath when they left its contents at the building; the feds only wanted the carton. As photographed at the National Archives, the box end in the 1963 picture is about 11 1/2" wide.

The two pipes pass through the seventh floor uninterrupted and my guess is they served for ventilation, possibly for toilets, sink or the AC. I believe the toilets and sinks were towards the back. So maybe one pipe was for AC fresh-air intake and the other pipe was to exhaust hot air the AC removed from office rooms below.

[Charles Collins]

Charles, it's no good measuring the floorboards in your house, the flooring in the TSBD is industrial, not domestic. Also, those pipes are definitely not conduit. I really don't understand why you guys are still struggling with this. You have the best standard measurement possible in the photo. As I posted earlier, 3no vertical courses of bricks plus cement bed is between 8''-8.5''. Now all you need to do is measure the 3no courses on your monitors with a small compass set and all the other measurements, floorboards, pipes etc, all fall into place. I've not done it myself but I'd be very surprised if the flooring isn't approx 6'' and the pipes 4''. 

PS If you try this don't forget the first course of bricks is only half visible. Measure the three above. Good luck.

Thanks Denis, I appreciate your input. Below is a photo showing the two pipes in question. Notice that the pipe on the left of the photo has been bent twice (forming the offset) and appears to me to be EMT electrical conduit. There are no fittings at the bends. EMT conduit is typically bent in the field in this manner with EMT tubing benders. And the couplings on the pipe at the right appear to have either one or two set screws for each section of tubing that helps to hold the EMT in place within each coupling. This is a typical type of coupling that I have used many times with EMT couduit.




Also, please note the box on the floor that the sniper would have sat on is approximately 11.75" wide (see photos below).






And Jerry's post of today shows a photo of that box (see below) clearly shows that that 11.75" side of that box spans approximately 3.75 floorboards. The arithmetic indicates each board to be approximately 3.13" (thanks Jerry).

[Charles Collins]

The vertical ruler on the bricks in the photo is on an angle to the camera (see upper-left inset). The photographer (the photo was taken on the 25th) appears to be looking down at a sharp angle. However, this would not affect much the inset ruler on the floor.

"Box D" is another way to approximate a sense of dimension. The box as discovered was resting on its top, so fingerprints were partially on the box's bottom. The box was opened from underneath when they left its contents at the building; the feds only wanted the carton. As photographed at the National Archives, the box end in the 1963 picture is about 11 1/2" wide.

The two pipes pass through the seventh floor uninterrupted and my guess is they served for ventilation, possibly for toilets, sink or the AC. I believe the toilets and sinks were towards the back. So maybe one pipe was for AC fresh-air intake and the other pipe was to exhaust hot air the AC removed from office rooms below.

Great post, thanks Jerry.