Owl Mountain Models

Below is a brief excerpt from the kit's intructions covering the history and roster of F-50-series cars built for the SP and subsidiaries:

OMM #2002 Kit F-50-5/8/9 with T-section Trucks and White Decals - MSRP $39.95

The 2002 kit covers the cars listed in Table 1 (above in the instructions) with the white decal set and also have the SPMW decals to model the 181 or so F-50-5/8/9s converted by 1956 to MOW service. Additionally some F-50-5/8/9s were reassigned and renumbered over the years.

The OMM #2002 and #2004 kits will have the standard SP F-50-sides, AAR/ARA T-Section Trucks, late style endsills, K & AB-schedule brake systems, and double I-beam centersills. Some kitbashing will be required for the PE cars which were modified for 45-foot radius operations.

2004 Kit F-50-5/8/9 with T-section Trucks and Post-1958 Black SPMW Decals - MSRP $39.95

The 2004 kit is for modelers in the 1960-1970s eras wanting to model these cars near the ends of their lives in MOW service. The SP painting standards changed in 1958 with the Gray and Red diesel scheme, the SPMW cars changed from Freight Car Red with white lettering to a light gray color body with black lettering. This kit is the same as 2002 Kit, but with the white decal sheet replaced with a special black SPMW set. The total number of cars moved to SPMW is hard to sort out, but the numbers converted totaled about 181 assigned to MW service by 1956, many lasted into the 1960s and 1970s in MW service. We'll be posting the SPMW's roster (as of January 1956) for modelers to choose correct car numbers for their SPMW models.

OMM #2003 Kit – SP F-50-10 & F-50-12 class cars with U-Section Trucks and White Decals - MSRP $39.95

SP 38809, a late first series F-50-10 with U-section trucks as supplied in Kit #2003 & 2005.

These kits cover the cars listed (shown below) with the white decal set and also have the SPMW decals to model the 36 or so F-50-10/12s converted by 1956 to MOW service. Additionally some F-50-10/12s were reassigned and renumbered over the years.

• SP F-50-10 class cars were built in 1927. This class totalled 450 cars for the SP in two number series.
• SP F-50-12 class cars were built in 1928-1929. This class totalled 500 cars for the SP.

The OMM# 2003 kit will have the standard SP F-50-sides, AAR/ARA U-Section Trucks, late style endsills, K & AB brakes, double I-beam centersills and white decals.

OMM #2005 Kit - SP F-50-10 & F-50-12 class cars, with U-Section Trucks and Post-1958 Black SPMW Decals - MSRP $39.95

The 2005 kit is for modelers in the 1960-1970s eras wanting to model these cars near the ends of their lives in MOW service. The SP painting standards changed in 1958 with the Gray and Red diesel scheme, the SPMW cars changed from Freight Car Red with white lettering to a light gray color body with black lettering. This kit is the same as 2003 Kit, but with the white decal sheet replaced with a special black SPMW set. The total number of cars moved to SPMW is hard to sort out, but the numbers converted totaled at least 36 cars by 1956, many F-50-10/12s continued into the 1960s in specialized service and may have been converted to SPMW service after the 1956 MOW roster. Also by the late 1950s many of the earlier class cars had received second hand trucks, making the 2005 kit a better starting point for modeling these converted cars in later MOW service. Many SPMW F-50-10/12s lasted into the 1970s. We'll be posting the SPMW's roster (as of January 1956) for modelers to choose correct car numbers for their SPMW models.

New Design for Narrow Draftgear

One area where we're pushing the limits with the new F-50-series cars is in the draftgear and endsills. During our development phase of this project, we observed that the F-50-series models are much smaller than what we're used to seeing in the hobby with the bigger boxcars (even WWI era USRA cars). If we put a full 1/4" wide coupler slot in the end of the car for a standard HO NMRA-Kadee box and reproportioned the other details around it, then the endsills looked very over-scale compared to prototype photos. We decided to try something new in HO scale.

SP 38909's end sill with 'near-scale' draftgear-shank opening and Kadee-156 coupler.

In 2013 we converted several test boxcars to use this new narrow draftgear-shank opening design. We 3D printed our first pilot model and tested it extensively in-service at a large model railroad club layout. Various positions in the train were tested, including putting the pilot model directly in front of a helper shoving on 40 cars on a 2% grade! The 3d printed pilot model did amazingly well in these tests that were designed to purposefully find problems with the design concept of the car.

We found that these cars performed very well and also worked down into tight 18" radius industrial spurs without any issue. The narrower coupler shank opening only became an issue when attempting delayed magnetic uncoupling on tight (18" Radius) curves. The Kadee-156 coupler heads and knuckles actually have enough freeplay (slack) in them that cars can stay coupled down to very tight radius (almost to the point of the corners of the two models touching).

We felt that in most operating conditions for the cars these days, the narrower shank opening combined with the extra 'slop' in the mating areas of the Kadee Scale Head couplers will perform well. Modelers running into any issues from the narrow draftgear opening can easily create more movement by filing extra width into the sides of the striker opening section of the box and continue until the needed draft gear movement is achieved.

New Lumber Loads

OwlMtModels is also looking forward to our next Modular Lumber Load Kit to go with the new F-50-series cars. This new kit will be a "Narrow" lumber load suitable for gondolas and the narrower F-50-series flatcar decks.

In addition, a second kit with extra lumber parts will be offered to fit 52-60ft flatcars and gondolas.

F-50-Series Add-on Kits

These will be small mini-kits which can be added to appropriate F-50-series flatcar kits to make unique and special assignment cars.

SP 36" Sideboards (SP Style) - These should be added to cars modeling SPdeM and UP F-50-4s as-built. Many T&NO cars had sideboards fitted for stone loading and other assignments. SPMW Supply Flats often had sideboards as well, when delivering smaller items such as barrels, kegs, boxes, etc.

Picture from several years ago of our early rendering of a the SP 36" Sideboard set. These will be injection molded with wire tie-rods and etchings for the internal braces.

"Beet Rack" - Blackburn-style (1930's-1950 version) - This rack sat on top of the car with turnbuckle rods to the corners of the car. The Blackburn design had four large side doors and no vertical stakes mounting into the stake pockets. This rack was in regular service until the G-50-20 and G-50-23 cars were delivered in 1949.

Picture from several years ago of our early rendering of a Blackburn Rack. These will be injection molded with wire tie-rods. We also plan to made a removable 'beet load' and side pieces to make the car look correct when loaded!

Additional Future Projects