Re: D&RG Class 3 and 3A Box cars

Eric -
Cutting the porch off may not mean what you think, and I have to somewhat doubt the Sloan description if this is correct -

<Class 3A Length over Frame - 25' 11 1/2" Porch Included - car ends held back
<Class 3 Length over Frame - 25' 11 1/2" Porch removed - car ends slid outward

I don't see this in C+10 - what's the source?

If the ends were slid out as stated I'd guess that 'cutting the porch off' meant removing the spring planks and straps, cutting the side sills back (minus the length of new tenons) and adding a new 6-1/2" thick end sill flush against the original end sill. That would allow the body to be extended keeping the same frame length (and making the 3a folio inside dimension wrong) and making the porch disappear (as opposed to being removed). I see evidence of the same type of change in other B&S rebuilds (EBT hoppers IIRC), which might support the notion.

But also note the change in truck spacing between 3 and 3a. 18' 1-1/2" (1881 plans) for the 3 vs. 17' 1/2" (folio) for the 3a. If anything this could indicate that Sloan was correct with the frame length shortened and the inside length remaining the same. Reason for the truck location change wouldn't be for weight capacity (same 4x8 sill size as later cars), but to maintain similar drawbar yaw in curves with the shortened frame.



Edited 2 time(s). Last edit at 06/14/2021 11:28PM by CR BT Dispr.