USAT F3A Tips


Posted on Feb 5, 2014

A used USAT F3A found it`s way into my possession today. I wasn`t planning on this, it just sort of happened. However, now I have another loco for the GIRR. The road number of the model is 26C. By the ATSF numbering scheme used at the time, this would be the trailing cab unit of an AA, ABA or ABBA set. The lead loco would be designated 26L. After


USAT F3A Tips
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ATSF stopped running them in matched sets, each loco would receive a unique number. Some of the locos in this class were eventually rebuilt as CF-7`s. This particular model is similar to the USA Trains GP-7/9 that I purchased in 1998 but it is of somewhat newer construction. I do not know the date of manufacture, but the switch board is dated 12 Aug 1999. This one has a bank of 5 slide switches underneath as opposed to the 4 switch configuration of my GP-9. However, other than some wiring issues, it appears to be pretty much the same. The model is well detailed and heavily built. It still has wheels with traction tires and sliders. Since my investment in this loco is really small right now, I`m not going to go far out of pocket to upgrade it so the existing wheels and sliders will stay on this one. The wheels are somewhat worn indicating that this one has some miles on it. However, they are not seriously pitted now and I intend to keep them that way. My GP-9 had serious wheel problems due to a combination of conditions that I now know how to mitigate. My layout has a really beefy DCC booster which can provide very high peak currents, in excess of 20 amps. The decoder I used in the GP-9 is also a very high current decoder to match the high current motors, which the F3A still has. The combination of high available current, motors with nearly zero stall impedance and no current limiting results in burned up wheels. I`ll not...




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