The need to model Amtrak trains over the Dunreith District of the CIOR would have to be faced. The biggest factor for me was finding a model F40 that ran smooth and quietly along the track. I wanted something that when finished would be able to handle a full sized "National Limited" train and do so at speed.
This lead me in search of the perfect F40. The one drawback was the price. I decided I would try to keep the cost around $100 and lower if possible.
When I started the search I figured I would consult with "Amtrak Buffs". I knew the period I was modelling, but since the route and actual train were no more, I would have to do a "what if". This lead me to the F40 and possibly a few Pooch units, but for sure the F40. Now, the delima was what company had the closest to accurate body out there. When this question was possed, I got "Walthers" as a 95% answer. So the search began on Ebay and a few other online retailers for the cheapest version of Walthers Amtrak F40 I could find.
Finally I found one, the cheapest thus far at $30. Once the unit arrived I tested it to make sure it worked, it did, but had a bad grinding and gear "wheeer" sound to it at even moderate to low speed. Now, I am not new to the hobby, and coming into this I figured I would have to make some modification to the unit. I am not super picky, but I don't run anything power wise that is Athearn, Bachmann or Walthers. I want something that runs like a Kato, P2K or Atlas. This would lead me to the "great find".
You will need these things from an Atlas Masters series engine
--Trucks
--Worm Gear
--Dual mode decoder
Start by removing the frame from the F40. You will now remove the trucks from the F40, keep the universal and drive line and set them aside for now.
Now, take the Atlas trucks and insert them into the frame of the F40. Remove the end to the Atlas worm gear and apply the end of the Walthers worm gear (universal) to the Atlas gear. Then add the gear back into the Atlas unit.
At this point you will want to leave one of the towers open and reinstall the drive line from the Walthers motor into the trucks. Once you have this done, remove the Dual Mode decoder and get it ready. You will now need some electrical tape. Apply it to the back (bottom) side of the atlas decoder (this will help it from shorting on the frame. Now, apply electrical tape to the top of the frame. The decoder won't fit down into the frame, but since it is so thin in profile it won't cause any issues. Now, simply hook up the wires from the trucks. The next step is to replace the lightbulbs. Although these bulbs are DCC friendly, they are not long enough to reach the head lamp holders and still have room to work. I use model power bulbs, but LEDs or other brands work just fine.
Once the bulbs are in, test the unit. If you are getting a grinding, this is the flywheels hitting the frame. Remove the motor and add some styrene into the frame, between the screw holes. Try a few sizes, to see what works best. Once you find the best size (and rid yourself of the grinding) CA the styrene into place, once dry, add the motor back in, level it in and your set.
Don't forget to put the new lightbulbs in place. Next, the side cab latter is to long. For the time being I just removed the bottom rung of the step. Later on when I repaint and do the correct mods to the unit I will replace this with a thin profile latter.
Now you should test run the unit, make sure everything tracks well and there isn't much noise.
For roughly $85 you have a fine running F40, and with some detail parts you have something that looks almost as good as brass and probably runs better then brass!
So far the unit I built runs smooth as silk. A few people have asked why I went with a Atlas Dual Mode decoder. That is simple, it was there at the time and fit well enough. Another reason is I had a spare in the decoder rack from a SoundTraxx decoder I installed on a SD35.
Check back soon and I will have pictures to go along with the story!
