B&O Tatum XLT Patent Detail Parts

Figure D1 -- A Six Panel Superior Boxcar Door with Help from James Mischke

Figure D2 -- Four and a Half Panel Superior Boxcar Door with Help From Bob Witt and Ed Kirstatter

Note four-and-a-half panels is the term Bob Witt provided me, if you have seen other five panel doors, the top one of this one seems cut in half.  And now what some in-progress work looks like picking out bits of blob here, bits of blob there from a photo (photo courtesy of Ed Kirstatter).  This is detail of the latching mechanisms and other panel add-ons.

Figure C1 – This is what the drawing for the N-25 Looks Like for the Moment, Photo Courtesy Bruce Griffin

Bruce Elliott sent me a photo of the slack adjuster on the O-41 at Elkins (if I got it right), here is the current effort from that:

Figure C2 – Photo Match for the O-41, with an Added Back Plate, Seems not Used in the Original

Figure C3 – The O-41 Drawing and Parts Superimposed on the Photo, the Pawl and Rivets Have Taken Quite a Hit

Here is a bit more quick work on the Tatum boxcar door.  These have been given basic thickening, I will use these to test how many of these fit in the minimum purchase cost at Shapeways:

Figure C4 – The Front of the XLT Boxcar Door for 3D Print Fit Test

Figure C5 – The Back of the XLT Boxcar Door for 3D Print Fit Test

All the Best,

Charles Sloane

PS, sent to Yahoo! and several of the guys.

9-13 July 2019:

Here is a variation on the slack adjuster below, it is for N-36 class cars:

Figure B1 - XLT Slack Adjuster Drawn for N-36 Cars next to image of Adjuster for N-34 Cars

Figure B2 - N-34 Drawing on Left, then N-34 Image, N-36 Image, and N-36 Drawing; the XLT Sack Adjuster

How about a gondola?  Here is some work in progress on the O-59 gondola.  Reading the fuzzy photo and adding the previous work and the resulting drawing; leaves some questions:

Figure B3 - O-59 Drawing Staged to Look Like Photo of Original, Notice any Difficulties on the Lower Right?

I could use a couple suggestions if available, though I have a couple ideas on my own to fill-in or not under the tail of the bracket.  The back plate shows no sign of extending there as I continue to examine the shadows.  The right edge of the back plate visible-ish (not much but there) above and below the pawl bracket is in a straight line, no excursion to support the pawl bracket tail.  Is this because the pawl bracket is a later addition?  The original patent drawings do not have this pawl bracket (The B&O Modeler, Number 44).  Explaining the pawl bracket does not seem that difficult, every time the brakes are applied, the linkage will try to unwind the ratchet, heavy applications of the brakes might put a lot of stress on the rivet holding the pawl, and tend to deform it.  Loss of the pawl during heavy braking would not help, tending to release the brakes like any linkage failure.  With the bracket supporting the outward end of the rivet, it is significantly strengthened.  Here is another view of the drawing to better show the bracket tail situation.

Figure B4 - Drawing of the O-59 XLT Slack Adjuster, Is Additional Support for the Rivet Needed?

At this moment, I am inclined to leave this as is, with the edge of the back plate providing sufficient support for the rivet and tail of the pawl bracket.

Any other thoughts?

7 July 2019:

Here is where this work started on the XLT devices.  The XLT slack adjuster drew my interest from postings to the B&O Yahoo! group.  I noticed the ratchet on the photos looked a lot like the ratchet I developed during the work on the B&O O-48 composite gondola for Ed Kirstatter.  And as best I can tell they are the same!  I am updating the original ratchet and pawl work based on the improvements I was able to make using the great photos and other information the folks on the B&O Yahoo! provided.  So here are some images of the slack adjuster, including first prints in S and HO Scales:

Figure A1 - XLT Slack Adjuster Left to Right; Full Scale 3D drawing, S Scale 3D Shapeways Print, HO Scale 3D Shapeways Print

PS, check below for another XLT image on the boxcar door.

Original Post:

This project is a specialty for the modelers of the B&O railroad.  More details to come.  For now here are some images of the work:

Figure 1 - XLT Brakeman's Steps for use with AJAX Hand Brake

Figure 2 - Not XLT but an AJAX Hand Brake in Progress

Figure 3 - Not XLT but Assorted B&O Ratchet and Pawl Items

Figure 4 - Not XLT but used on some B&O a Small but Visible Part of the Duryea Under-frame

And to wrap-up for today:

Figure 5 - Some Startup Work on the Tatum XLT Boxcar Door

NEW 7 July 2019:

Figure 6 - Some Exploration Work on the XLT Door Using the Vertical Cross Section from the Patent

Happy Modeling Everyone!

Charles W. Sloane