B74A horse car


Bruce Smith
 

Folks,

As I noted, I am building a Bethlehem Car Works (hereafter known as BCW) B74A, kit #453.

Today I did some parts clean up. This included removing the sides, doors, and kick plates from the brass carriers and filing off any nubs. I also filed the backs of the kick plates to remove any overhanging flash. I drilled the grab iron holes in the sides and doors with a #79 bit. I was surprised at how easy these were to drill out. I did lubricate the bit with some candle wax. 

BTW, if anyone says that "the age of real modeling is over", just hand them one of these kits. Nothing fits out of the box. period. And stuff is missing. Case in point, the 0.040" x 0.060" styrene for the ends. None in the kit. I made up some by laminating 0.020" x 0.060" strip. I went to glue these to the ends, with the requisite 0.020" inset, except that there is a DITCH in the back of the ends (most likely for the styrene B60B which I believe that they were used for. So out comes the putty (Bondo Glazing and Spot Putty works great!) to provide a flat surface to glue the strips to. 

Before going crazy with assembly, I decided to make sure everything is pretty much the right size. The ends, resin roof, and floor (sheet styrene in my kit, yay! No more roller coaster ECW floors!), were all almost exact the same width. That's fine for the roof and ends (although the top contour of the ends and the bottom contour of the roof are not a match...YIKES!) and the floor is just a hair too long (like 0.010"). But, remember that 0.020" clearance on the ends? That's the thickness of the brass sides. So the floor must be thinner than the roof and ends by the thickness of 2 sides, of 0.040". 

But wait! There's more!  The sides are shimmed at the base with 0.020" styrene. That also has to come off the floor, so ANOTHER 0.40" has to come off. Time to trim that 0.080" off the floor!

George asked about the underbody. Without a drawing I'm going to guess that these cars had the same 18" channel center sill as the P70 series. Back in that project we used either 3/16" evergreen channel, or, a laminated beam of three 0.060" x 0.187", with a 0.010" plate.  So, I laminated up a 0.180" x 0.187 center sill that will receive a 0.010" cap later.

Now I'm starting to think about assembly. I would like to pose one set of door open, with interior details to be seen. That shouldn't be an issue, but I've hit a real question point around the doors, and it doesn't matter if they are open or closed.

The doors are about 0.020" thick, and they are glued to 0.020" x 0.080" strip that frames the door opening. That means that the doors add an extra 0.040" thickness. That would be fine if the floor was under the door, but it isn't. The floor is positioned by a 0.020" x 0.130" strip on the car side, capped by 0.060" square strip as a stop for the floor. HOWEVER, the bottom of the side at the door opening is 0.104" from the bottom of the car! This means that the top of the floor is roughly 0.025" ABOVE the bottom of the opening at the door. I can solve that by using 0.100" strip instead to get the floor lower, but that doesn't solve the door problem as the doors are pretty much the same height as the sides (and in fact, it looks like the doors will need to be filed on top a bit to allow them to be moved up so that the grab irons are properly located. Ultimately, it looks like another 0.040" of the floor width will have to be removed for each door to allow the floor to actually fit... or the bottom of the door will need to be trimmed flush with the floor. I'm probably going to do the latter. 

Confused yet? Me too!

Regards,
Bruce 
Bruce Smith
Auburn, AL


Rich C
 

Bruce, The BOM needs close study also, if I recall, a variety of drill bits. I am going to do a Theatrical Scenery Car first, as I mentioned I have two of each. My plan is an as delivered and a modernized version (if appropriate) of each type. I don't think it would be wise for me to tackle all four at once, just reading what Bruce mentioned on his initial start.

As far as detailing the underbody, I believe using the detailing methods that have been done on the Mail cars would also apply here, just my guess. I believe Dave had done a very thorough job on his M70B and I will follow that unless someone has a different approach or a diagram.

Rich Christie


O Fenton Wells
 

Bruce, I have the Southern version yet to start. I may hold off for a while. After your synopsis I may scratch build the sides.  I will build the BE version with the windows blanked. And not sure I like how much the window openings (stamped) stick out on the car sides in the kit. 
Can’t wait to see your PRR version 
Fenton 


On Jan 1, 2022, at 9:38 PM, Bruce Smith <smithbf@...> wrote:


Folks,

As I noted, I am building a Bethlehem Car Works (hereafter known as BCW) B74A, kit #453.

Today I did some parts clean up. This included removing the sides, doors, and kick plates from the brass carriers and filing off any nubs. I also filed the backs of the kick plates to remove any overhanging flash. I drilled the grab iron holes in the sides and doors with a #79 bit. I was surprised at how easy these were to drill out. I did lubricate the bit with some candle wax. 

BTW, if anyone says that "the age of real modeling is over", just hand them one of these kits. Nothing fits out of the box. period. And stuff is missing. Case in point, the 0.040" x 0.060" styrene for the ends. None in the kit. I made up some by laminating 0.020" x 0.060" strip. I went to glue these to the ends, with the requisite 0.020" inset, except that there is a DITCH in the back of the ends (most likely for the styrene B60B which I believe that they were used for. So out comes the putty (Bondo Glazing and Spot Putty works great!) to provide a flat surface to glue the strips to. 

Before going crazy with assembly, I decided to make sure everything is pretty much the right size. The ends, resin roof, and floor (sheet styrene in my kit, yay! No more roller coaster ECW floors!), were all almost exact the same width. That's fine for the roof and ends (although the top contour of the ends and the bottom contour of the roof are not a match...YIKES!) and the floor is just a hair too long (like 0.010"). But, remember that 0.020" clearance on the ends? That's the thickness of the brass sides. So the floor must be thinner than the roof and ends by the thickness of 2 sides, of 0.040". 

But wait! There's more!  The sides are shimmed at the base with 0.020" styrene. That also has to come off the floor, so ANOTHER 0.40" has to come off. Time to trim that 0.080" off the floor!

George asked about the underbody. Without a drawing I'm going to guess that these cars had the same 18" channel center sill as the P70 series. Back in that project we used either 3/16" evergreen channel, or, a laminated beam of three 0.060" x 0.187", with a 0.010" plate.  So, I laminated up a 0.180" x 0.187 center sill that will receive a 0.010" cap later.

Now I'm starting to think about assembly. I would like to pose one set of door open, with interior details to be seen. That shouldn't be an issue, but I've hit a real question point around the doors, and it doesn't matter if they are open or closed.

The doors are about 0.020" thick, and they are glued to 0.020" x 0.080" strip that frames the door opening. That means that the doors add an extra 0.040" thickness. That would be fine if the floor was under the door, but it isn't. The floor is positioned by a 0.020" x 0.130" strip on the car side, capped by 0.060" square strip as a stop for the floor. HOWEVER, the bottom of the side at the door opening is 0.104" from the bottom of the car! This means that the top of the floor is roughly 0.025" ABOVE the bottom of the opening at the door. I can solve that by using 0.100" strip instead to get the floor lower, but that doesn't solve the door problem as the doors are pretty much the same height as the sides (and in fact, it looks like the doors will need to be filed on top a bit to allow them to be moved up so that the grab irons are properly located. Ultimately, it looks like another 0.040" of the floor width will have to be removed for each door to allow the floor to actually fit... or the bottom of the door will need to be trimmed flush with the floor. I'm probably going to do the latter. 

Confused yet? Me too!

Regards,
Bruce 
Bruce Smith
Auburn, AL


Mark Taylor
 

Hello Bruce, I am following this build very closely as I have a few of these cars that I would like to get built myself. The cars I have are the brass sided models. Upon inspection of the included parts I have found the resin cast "door" end is almost .060 wider that the other car end "plastic". Was wondering if your car ends where like mine, not sure how you can build a '"square/ rectangle" car if the sides don't measure the same. Any thoughts would be greatly appreciated. Best Regards; Mark Taylor