Wednesday, July 6, 2016

SP 65ft Mill Gondolas

Tonight I will talk about Athearn's R-T-R 65ft mill gondolas.

The Prototype
The 65ft mill gondola with drop ends started being built just before WW2.  The drop end doors were fitted for carrying loads longer than 65ft that were in high demand in the steel industry for structural shapes and other long items from the "rust belt" during the early part of WW2.  These cars were also built unusually narrow, around 8 feet wide.  As the length of the cars grew, the standard clearance plates for curves meant the cars also had to get narrower to be able to fit around the same curve a 10' wide 40ft box car could without sideswiping any track side obstacles.

Below is one of the PRR G26/G26A cars that Athearn produced.  These cars run so well I am happy to have some minor differences in the ends of the model car compared to the 2600 prototype cars of this type that the PRR owned!  These models are also reasonably accurate for many other prototypes as well.

PRR 440703, a G26A, is one of the Pennsy RR's huge fleet of 2600 65ft mill gondolas.
In this post we will focus on the four classes of SP cars, totaling 305 cars.  SP bought their cars to cater to heavy lumber industry interests in Northern California and Oregon and also some of their other customers around the system including 50 cars for the Texas & New Orleans.

G-70-2, 15 cars blt 1941
G-70-4, SP 40 cars & T&NO 50 cars blt 1942
G-70-6, 100 cars blt 1950
G-70-9, 100 cars blt 1953

The Models
First produced around 2005-2006, these are one of my favorite models in terms of mechanical setup.  In 10 years of regular running at the club of nearly 20 of these cars, I don't believe there's been a single car derailed from a cause I can track to the mechanicals of the car itself.

Top view and interior of Athearn 65ft mill gondola with drop end doors and steel floor.
The mechanical construction of these models is rather unique in HO scale.  They have a die-cast metal underframe and floor.  The sides and drop end doors are cast plastic,  While these cars only weigh about 3.25oz with all-metal wheelsets (Intermountain), they have a Center-of-Gravity test of 120 degrees and a rollablity of 1%.  Yes, the car can be nearly inverted on its back and still right itself to its wheels!

Underbody of Athearn 65ft mill gondola - The whitish marks are chips in the paint revealing the cast metal floor.  Also notice  the areas behind the 'fishbelly' sides is not packed with weight!
This combination of VERY low CG and better than average rolling qualities means, according to the LMRC club standard that the car meets the adjusted weight standards.  In a future post I will talk more about these standards and how we quantify them.  It is enough to say here that mixed car type trains of over 100 cars can easily be operated without any issues when cars are properly built and adjusted.  The couplers on these models were replaced with standard Kadee No.5 head, whisker-type couplers.

SP 160550 
This was the first car of the G-70-9 class.  For some reason so far Athearn has only issued painted models for the G-70-9s built in 2-53.  Hopefully in the future they will make some of the earlier class cars as well.
SP 160550, G-70-9, Built 1953
SP 94296
To round out my other 65ft SP mill gondola cars I have redecalled two models to backdate them for G-70-4 and G-70-6.  I decided not to number any of my cars for the G-70-2, as only being 15 cars,

SP 94296, G-70-4 Built 1942
The SP 94296 I wanted to try a new weathering technique on.  I had the chance to collect some powdered rust.  As this car would have seen heavy service during WW2 and in total about 11 years of service I decided to try some rust powder.  The inside of the car has steel floor plates as well.  I tried first dusting on the powder like chalks, then over-spaying with dullcote.  However like most chalk weathering and dullcote the sealing coat tends to dull the effect of the chalks.  Also the car body being nearly rust color originally as well didn't help!
I tried a different technique then.  Spray the inside of the car with a fairly heavily with dullcote and then pour some rust powder into the wet clear dullcote.... using an old brush I quickly swooshed the powder around the interior and the lower sides sticking it into the tacky paint.  This worked perfectly and ended up giving a large variety of colors from the same rust powder.

SP 160023
The SP 160588 was the number on my third G-70-9.  Deciding that I wanted to backdate it to a G-70-6, I redecalled it as the SP 160023, built in 1950.

SP 94296, G-70-6 - The car's been renumbered, but I've not yet redecalled the tare year or class number.
This model was lightly weathered with a mix of PollyScale paints roughly the same color as the carbody.  I use similar colors when I want to knock down the brilliance of the white lettering on a car that has been around a while, but other weathering such as rust hasn't really started to set in yet.  I also like doing a coat of road grime and dust along the lower carbody to varying levels.  I also tend to use slightly different colors for this as these cars will have been coming from different parts of the country and seen yet more variety of clements and weathering conditions on previous trips.

SP 160588, a G-70-9, before I renumbered it to become SP 160023, a G-70-6.
Conclusions
That will wrap it up this time for these very nice operating 65ft Mill Gondolas.  When I get some other photos together of the removable loads for these cars, such as the one above, I'll make another posting.

Jason Hill

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