Hi,
Apologies for the lack of updates on this thread. Progress took a bit of back seat position due to work and family commitments of late, but I`m now back with renewed enthusiasm to get this loco out on the line earning its keep!
I masked up all the glazing and got a few coats of gloss varnish on so I`m now ready to start applying the decals!
I also made one last modification as I had found in the past that these locos occasionally tend to stick on some of the frogs of our points due to their slightly shorter size. The USAT GP9 is just a little larger so it doesn`t have this issue, but there was something about the wheel spacing on the F units that seems to cause the odd problem here and there. Anyway I decided to try swapping out the wheel sets that have traction tires for just normal standard wheel sets. Due to the presence of the traction tire, these wheels do not really make contact with rail head so this means that effectively there are two less axles making electrical pickup.
I borrowed a pair of plain, tire-less wheel sets from another F3B unit just to experiment, and this seems to make a really big difference! Now all four axles are making constant electrical contact, plus the four pickup skates, so the loco is extremely smooth without the need for anything else like a capacitor. Fortunately these wheel sets are available as spare parts from Charles Ro (USA Trains spare parts dept.) so I think I`m going to do the same modification for all of our F units in the future.
I guess obviously there would be a certain loss in pulling power, but we don`t run excessively long trains on our line, plus this is a good reason for justifying the need for an added B unit behind!
I will post some photos of progress as soon as I can.
Thanks,
G
Here is a quick photo (not mine!) of a USA Trains motor block. As you can see, the wheel at the front has a traction tire and the wheel at the back is just a normal wheel set. As the thicker rubber traction tire is making contact with the railhead and not the actual wheel face, it can sometimes mean that this axle is not picking up power as it should:
