Westerfield SP B-50-2 Kit (Part 1) - SPMW 2257 Ready Box Car

For those following my blog building my Sunshine and Westerfield B-50-15s, a couple years ago I was able to get an (old) Westerfield #1700 undecorated B-50-1 flat kit, which I'll be building as SP car.  I've wanted to start building it on and off since I got it.  The B-50-1/2/3s would have been basically completely out of revenue service by my modeling period covering the 1945-1954 era.  I also snagged a UP B-50-1/2,4, which I'll be converting to an SP car.

SP B-50-1/2/4 class boxcar with roof resting in place and grabs in holes.

A number of these cars were still in service showing in the January 1956 SPMW Roster, however they were cut down to flatcars with or without stake pockets.  While I could do that, I want to make the Westerfield kit up as one of the Ready Boxes or a Tool car, which would allow it to be showing up on the Jawbone Branch as a tool car, or other local material car for the MW crews at Little Lake, or wandering up to Owenyo.

Basic Kit Parts

Flat kit parts for UP B-50-1/2 with pressed steel ends

Light gray resin parts of the UP B-50-1/2 flat kit.  The ends are cool, as the A-end has the lumber door.

Body Assembly

Extra ends from SP B-50-1/2 kit & styrene corner strips of 0.040" x 0.080" applied to floor and sides.

Looks like I didn't photograph the end-side assemblies.  Unlike the B-50-15, SP 32451 which I was working on last week, I decided to make two end-side sub assemblies and then mount them to the floor.

Assembling first end-side and floor gluing in to help square the corner.

The B-end wall casting from the SP B-50-1/2 kit is 'dark' high-density weighted resin, which is much more brittle than the regular light gray resin.  Of course, during sanding the back and edges of the end casting, I caught the edge of the draftgear opening and cracked it into two pieces.  I ended up gluing it back together with 0.010" styrene sheet splice and ACC/CA glue.

Second end-side glued to the floor.

I marked on the Floor interior the prototype car research information stats.  I'm contemplating doing this model as Tool car, SPMW 1759, ex-85000, one of the B-50-2s.  Conversion to SPMW service was pretty early in 9-16-1929.  I'm not sure if it was first assigned to some other service, but by the 1956 SPMW Roster, the car shows as a "Tool Car" with no additional information.  This should suggest that the car doesn't have any windows or extra grab irons or stirrups added.

Reassigned interior notes, now for SPMW 2257, Ready Box.

After marking the interior of the body with the later ends on it to be SPMW 1759, I reconsidered if the 1759 should actually be using the earlier end, which might have still had the short grab ladder on the end in 1929.  While the first body has the later ends, would be a better car for something like SPMW 2257, ex-85826, was retired in 5-14-41 and assigned as a Ready Box.

With the second end-side sub-assembly glued in place completes the basic body.

The exposed exterior ends of the bolsters are going to be covered with the sidesill castings.

Underframe Assembly

The sidesill frames needed the top exterior side beveled with a X-acto blade

The sidesill frames needed some beveling of the upper exterior side, which will allow it to fit into the space between the bolsters and the interior edge of the sides.  ACC/CA glue then applied and the frame sidesills were inserted and glued in place.  Next come a pile of smaller resin C-channel crossbeams and drilling out the bolster/coupler holes.

Basic view of underframe with B & A-end marked.

Center marks with mechanical pencils on the coupler mounting pads.

Drilling Holes

Tool: Foam-Core Support

I decided to support the interior of the B-50-2 with some closed-cell blue foam.

This allows me to drill the bolster holes, coupler holes, and grab holes without the body collapsing.

Bolster Holes

Standard 2-56 tap-drill working on opening the bolster hole for tapping.

Holes for Bolster & Coupler screws are drilled and tapped for 2-56 size threads.

Drilling Grab Holes

Roping staples didn't survive drilling out, so carving off.

I ended up not getting the resin roping staples drilled out, and damaged several of them.  So I'm carving them off, drilling them out and replacing with OwlMtModels #1010, Harriman Standard Roping Staples.

A-End drilled with No.78 for grab irons.

End grab iron ladder drilled out.  End sills will need to be fitted and then drill the grabs on the end sill out still.

B-End drilled with No.78 grab irons.

Same for the B-end.  When it comes time to detail the end, the hand brake platform will be fitted.

Couplers & Endsills

Resin endsills and Kadee 242 boxes, with pre-weathered Kadee 158s ready to install.

The endsills are cast in a sheet, so they need to be sanded and cut out from the sheet.

Sanding lower end to fit endsill casting

  The coupler boxes need to be trimmed shorter on both ends to fit between the centersill and the carrying iron under, cast as part of the endsill-striker casting.

A-End endsill installed

The endsills needed a bit of sanding on the back to provide good fit into the corner braces, which provide a corner to surround the endsill.

Otherside of A-End endsill close-up

Once the endsills are glued in place, I will need to drill out the grab iron holes and each side of the striker casting.  I'll probably also mark and drill a hole for the trainline air hoses.

B-End endsill & carside

The A & B-end coupler pads are drilled for the coupler box.  I usually take a coupler, insert it to the operational position on the coupler pad, then mark with a mechanical pencil the cross-car centerline of where the center of the coupler screw needs to be.

B-End endsill close-up.

Once I prime the car, I'll see if I need to do any re-scribing of the A-end boards where the crack happened in the casting.

Flipping Its Lid

B-End coupler installed - Box down

Generally, I prefer to support the coupler with the "Box" side of the assembly and sandwiching the "lid" onto the floor.  This initially resulted in me mounting the A & B-end boxes opposite sides up.  

A-End coupler installed - Lid down

On this car with the endsill including the "carrying iron" supports the underside of the coupler.  Therefore, I feel better about using the box against the car floor, and the lid on the bottom unsupported except by the screw head and the carrying iron of the endsill.  After deciding to have the boxes mounted with the "Lid down" orientation, I flipped the B-end over.

Underframe Detailing

Crossbeams

One of the signatures of the early Harriman-era freight cars is that the cars were built with very heavy crossbeam construction in the underframe.  

The B-50-1/2/4s on the SP had four heavy-weight beams around the center of the car, and two medium weight beams at each end.  By the B-50-6 and following series of design, the crossbeams dropped to only moderate-light weight beams.  By B-50-8 the 1/3 length between bolsters had heavy crossbeams, with lights spaced out to fill in.

Brakes, Levers, & Rigging

I went ahead and fitted the KC-brake on the car at this point.

KC-Brake Cylinder

The SPMW 2257 retired in 1941 still should be equipped with KC-brakes.  Tichy K-brake sprue is included in the kit, and I'm using one of the K-brake mounting brackets, with some slight modifications to the outer top flanges.  The KC-brake mounts between the two center heavy cross beams.  The KC's reservoir towards the A-end mounts onto the heavy crossbeam.

Completed underframe beams & KC Brake.

I've used ACC/CA glue on all of the styrene-resin joints and Tamiya liquid plastic glue on plastic-plastic joints.  I've carved off the roping staples, and will be drilling and replacing them along with the grabs later.

Levers & Rigging

I'm using the Tichy brake levers with 0.012" wire for the rods and custom bending the lever hangers.  The levers and rods will come in Part 2.

Archbars or Andrews Trucks?

I did a bit of filing on the bolsters to re-level them so the trucks track square on the rails.

Test fitting Accurail Andrews trucks under SPMW 2257.

Looking in Tony Thompson's SP Freight Cars Vol.4 Boxcars, most B-50-1/2s seem to have arch-bars or Andrews replacement trucks.  On the SPMW 2257, which was retired in 1941, I believe it would have replacement trucks.  Arch-bar trucks were out-lawed in interchange rules in 1940.  This particular set of trucks are newer Accurail Andrews trucks which came with the Accurail NC&StL 15337 kit which was upgraded with AAR U-section trucks.  Always good to see good trucks finding a good home!

Weighting Centersill & Interior Floor

Basic body of SPMW 2257, before weighting = 1.4 Oz. (No trucks wheels, no roof)

Basic Car (w/o metal wheelsets): 1.4 Oz

Roof  only: 0.1 Oz

Metal wheelsets & trucks: 0.6 Oz

At this point I do some rough mock-ups with the body, with weights in the right places to test how much weight I will need to put in to get the ideal final weight.

Estimates for Car Stats (based on LMRC Car Standards):

% Rolling: 1.5% (3.75 Oz Nominal Weight & standard trucks used)

CGI: 45 Deg (35+2x5 Deg reductions)

Resulting Weight Reduction Allowance for CGI & %R = -0.25 to -0.5 Oz (based on 40 or 45 degree CGI deflection).

Resulting Ideal Car Weight: 3.5 Oz

I'll probably aim for the car to weigh 3.3 Oz, as there still will be some bits of wire, details, etc to add and that may actually make the CGI worse, as they will be high in the car.

Centersill Weight

SPMW 2257, with centersill weight & trucks with 'shop' wheelsets installed.

Size: H 0.250", L 3.945", W 0.135"

Tapers: = 1.310" from each end to H 0.160" deep

Totals: 0.2 Oz, Total Car Wight: 1.6+07 Oz

As two 0.060" thick pieces ACC/CA'd in place.

Floor Weight

1/16" Lead sheet weight, marks indicated weight estimates for cutting down the weight.

Size: L 4.03", W 1.027", H 0.068"

Totals: 1.8 Oz

Addition of car components: 1.8+1.6+0.7 = 4.1 oz (Target Weight 3.3 Oz)

This will obviously put me about 0.8 Oz too heavy.  Which means I should cut the weight to 2" in length, I could narrow it, or I could make a new weight from 0.03" stock.

Modifying Weight

Cut down weight

Cut down to: L 1.68", W 1.000", H 0.068", Weight: 0.7 Oz

Re-addition of car components: 1.8+0.7+0.7 = 3.2 oz (Target Weight 3.3 Oz)

Roughed up weight and floor of car.

As usual, I roughed up the floor and weight so the RTV silicone will be able to hold it better.  I applied a bead, about 1/4" wide and about 1/16" thick to the weight and then pressed it onto the floor of the car.  A larger sheet isn't needed, as the centersill weight and metal wheelsets really do help the CGI.

Weight RTV'd onto floor

  The car comes up to 3.1 Oz, which I should probably look to adding another 0.2 Oz.  If I can get the car to roll on 1.0% grade, then I could loose another 0.5 Oz, which would cover the difference.  Most good quality plastic trucks with metal axles can be reliably roll on between 1.0% and 1.5% grades.

Sub-Roof Assembly

Roof panel parts & roof frames.

The resin roof frames are used.  Sharpie marks are made on the car side at the center and every 1/3 of the way to the ends (about 0.900").  A peak-beam of 0.080" x 0.040" strip styrene is cut to length of the sides to fit between the ends.  

Blue-foam into the body to support the center roof frame while the ACC/CA cures.

This size styrene is correct to fill the notch in each of the roof frames, which allows me to control the resin roof frames from bowing.  The sides are slightly bowed inward, without the peak beam the roof frames bow out of square by about 1/16".

Completed sub-roof structure.

I used my sanding pad to bring the styrene strip down to match the roof frame contours.

In Closing

Wrapping up the main body construction

I'm going to wrap up the first part of this construction at this point.  I don't want to continue fitting the roof.  I need to mount the grab irons in their holes and then apply thin ACC/CA glue to the interior of the body around the grab iron legs which extend into the interior space.

Jason Hill

Related Articles:

SP 32451 (Part 1) - Sunshine B-50-15 Resin Kit

36ft Fowler Boxcars - NC&StL 15337 (Part 1) Accurail Kitbash

Jawbone Freight Car Roster - Update 2022-06-26