USA TRAINS F3 replacement motors

So now I find that, in some of the motors, the piano wire looking long pickup wire between and under the axles has been rubbed all the way through and three of the four are broken off and therefore are no longer under the silver axle part and then of course not picking up power.
Broken Pickup Wires.jpg
So what type of wire do you think this is? I can't find these in the parts list. Are they just steel piano wire?Because this truck is only picking up power through two worn out shoes and one barely hanging on wire.
 
True that the wires soldered to the sideframes are power pickups at each axle. So what are the wires for? More pickup? Spring Tension on the axles?
 
Greg, I am humbled by the scope of what you have done. In a forum, I had hoped to find folks with experience with what I am working on. I am an old model railroader, but never dived in deep on G scale. Mostly I play with wires and love mechanical things that go, move etc. Trains fit that mold. I had not expected to find a whole website detailing exactly what I was working on. Oh my goodness, I am following in some big footsteps, it appears. I have been reading and reading. There's a bunch to read. But, It's good to know I was heading in the right direction. The sleeving of the cracked axles is fascinating and I have both drill press and arbor press so I will eventually try this with the old axles. I did check the new axles for cracks and they looked good for now. Time-wise, the price of new motor units is probably less than the cost/time into repairing them. But I still want to try it, ha ha. I need to grab my calipers and look up the specs for wheel spacing. (It's probably on your site, right?) I ordered my new motors from OnlyTrains.com. Do you recommend any other places to purchase parts? Thanks!
 
If just one end of the pick up "piano wire" has gone I loosen the screw holding it in place and move it along a little so both axles touch.

I wouldn't agree with the the comment in the link that says "DON'T open these blocks unless you NEED to". USAT instructions say the loco should be re-greased every 50 hours of running. I'm sure nobody knows how many hours each loco has run so I take every one of mine apart over the winter to clean and re-grease them. This keeps them running nice and smooth. If a USAT loco starts to run like it needs new plugs and points giving the pick up wires inside the truck and regreasing the axle housings with conductive grease seems to help a lot. My fleet all run as smoothly as the day I bought them and some are over twenty years old with a lot of hours running on the clock.

The cracked gear problem only seems to occur on earlier models, I wonder if they changed the design slightly on later ones. I picked up some spare wheelsets when I was in Boston as they are reasonably cheap if you don't need them posting to the UK and have also repaired a few wheelsets myself with brass tube. The brass tube repair seems to work although I ended up making a cut in the tube to get it over the plastic axle and then soldering it together once it was on. My early build F3 AB unit which I bought secondhand has had all the wheels replaced (by me) while my later build GP38s and GP30 have not had any problems of this nature. Although the F3 was old it didn't look like it had had much run time.

When re-assembling a power truck three hands would be useful. As I only have the regulation two hands my technique is to get the wheels in place with the baseplate close at hand. Jiggle one set of bearings correctly into place and then press down on the wheels with my thumb and little finger to keep the bearings correctly in place. I then jiggle the other wheel bearings in place and push down on these wheels with the first and second finger of the hand that is holding the other wheels in place. With my other hand I wiggle the base plate past my fingers, drop the baseplate in place and then hold it with the same hand until I move my wheel holding fingers to holding the baseplate. I then use the hand that is now spare to drop in the screws and tighten them up. This sounds a bit of a faff but, with practice, it is a very quick and easy way of getting the bearings seated correctly and the baseplate on correctly.

One very important thing for folk to remember and was pointed out on the link - the orientation of the bearings on the six wheel truck is opposite to the orientation to the four wheel truck i.e. diamond shape rather than flat.
 
There's really not enough extra wire to reposition, I'd recommend replacing it.

Chris, I will have disagree on several points.

I cannot tell you how many people have destroyed their gears by pulling apart and not putting back together. I have many people contacting me in emails about trains, and this is by far the most common experience, someone gets a cracked axle, opens it, and reassembles wrong. I stand by my opening admonition "don't open unless you need to"... i.e. don't open because you are curious, etc.

Just 1 month ago, I was presented with this: (not my loco)
44tonner_destroyed.jpg


Also, properly greased, you don't need to open these as often as you read. USAT actually has had that admonition for a long time, and I've never had a block run dry. A good suggestion is use good grease that does not get thrown from the gears. I do know a couple of people who put a lot of miles on their USAT locos, and they drilled holes in the bottom so they could grease without opening, and have little snap in rubber plugs or even black electrical tape over the holes the rest of the time.

I used to assemble motor blocks the way you do, but they still popped out of place sometimes when placing the cover on... using rubber bands to hold the axles in place is much more foolproof and can be visually inspected easily.

The "improved" axles only have a different knurling on them, and while the incidence of cracking is less, it still happens. USAT makes a lot of money on replacement axles.

I do speak from experience, and I have never chewed a gear up, I have locos from 2000 running fine (with repaired cracks) and I have way over 20 USAT locos, so I would submit my statistical sample is above average, and valid.

Regards, Greg

p.s. the most critical lubrication point is the axle bushings, which can be lubed without disassembly, and the journal bearings, which get all the wear and weight of the loco.
 
Hi again, picking apart the front light board. I see LEDs and incandescent bulbs. Three wire connector looks like red to number boards and J6 connector. White to J5 connector. Black is ground for both. So is J5 the Headlight and J6 for number boards and drum? 2 pin connector obviously runs the LEDs through the diodes and resistor for the ditch lights. And then J7 goes to the cab light, it appears. Have I got it right? Several of these wires are broken off so I'm making best guesses. Got a wiring diagram out there? I see an LM317 hooked to the front weight. What are we varying voltage to?
 
Follow Greg's links...
You are in for a world of pain, trying to un-tease how USA Trains (and Aristocraft) have wired their lighting boards..

The easiest / always-works method is to leave it all alone.. Break-out track and motor wires, and wire to decoder / RC ESC / what ever..

Then take a feed of DC (bridge if dcc) and a DPDT relay.. Relay un-energised feeds the original track-power points of the USA Trains board, to give forward-running lighting.. A 'voltage' (function output, RC trigger) is used to switch this relay when running in reverse..

Then if you want to control smoke, possibly another relay, and remove the smoke power feed(s) from the original board..

PhilP.
 
Unfortunately the F3 is one of the worst locos, several different voltages, and the stupid bipolar red/green led. Don't mention the common ground that wants to be changed to common plus for DCC.

I did indeed detail what I found and did, and took it as a challenge to keep as much of the original lights as possible, but for most people I'd either supply voltage to the main board (see my quick and dirty install)

USAT DCC installation techniques

Greg Elmassian web site on large scale trains and garden railroads, cigars, and computers
elmassian.com elmassian.com

Or just rip out all the existing lamps and replace with LEDs, and there was never a red classification light in the front, so pull that stupid red/green led out, and either find a white/green (tough) or pick a green or white led.

Greg
 
Thanks again for the links. In picking this apart I am wondering if I have misinterpreted what you have written or possibly found a small error in your second paragraph under "Basic Wiring Info..." where you state that: "The connector with 4 wires is the motor, and the one with 2 wires is the track power pickup" Is this correct? The diagram I created (to remind myself how the track pickup and motor connections work) has that the other way around. The connector with 2 wires is the motor, the and the 4 wire connector goes to the whisker/shoe plus sideframe connections on each side. My diagram leaves out all the other lighting and smoke wiring to keep it simple. Not trying to offend anyone...just trying to make sure it's clear for the next guy.F3 A Wiring.jpg
 
As PhilP and Greg Elmassian stated, AristoCraft and USA trains product may vary in content from time to time.

Be Careful.

---Hutch
 
I'm working on the light boards now. I find your notes to be in agreement with my tests. I was surprised that the 3 volts to the number boards and cab was regulated. I put some 3 volt LEDs I had laying around in place of the GOW bulbs that were there (broken, but there) and figured the number board would be shutting off when I hit reverse, but they don't! Mine are 5mm and kinda bright. Still gotta figure out a diffusser or damp 'em down with a resistor maybe. QUESTION: In your notes you are measuring the current draw with the GOW bulbs, right?...... When you say "They drew 135 ma at 3 vdc". So, the last sentence where you say "This would require a 126 ohm resistor at 2.3 watts" What do you mean by "This"? Can you explain a little deeper what you are getting at here. Are you talking about when you replace them with an LED? I probably need to go refresh my electronics knowledge as I'm a little rusty and uncertain as to if I can just directly replace the GOW bulbs with 3 volt LEDS. What have you tried since you typed up your web page?

Thanks, Dave (the D in DVS4G)
 
My resistor calcs are based on my DCC track voltage of 24 volts. This was to power these existing bulbs from my decoder.

24-3 volts = 21 volts, so I did a calculation to see what kind of dropping resistor was needed.

What is often overlooked when trying to run a low voltage component from 24v track power with a resistor is how quickly the wattage runs up.

P = I squared times R , so .135 squared times 126 = 2.29 watts...

The lamps for the number boards work well and diffuse the light well, doing this with LEDs is a challenge, might need an array of surface mounts with a thick milk white diffuser... otherwise the hot spots look terrible.


OK, you CANNOT replace incandescent bulbs with LEDs, the factors that limit them from burning out are COMPLETELY different.

Incandescent bulbs limit on voltage, LEDs limit on current.

You should study LEDs on how to use them.

Here's what I wrote, but it's not super great...

LED Lighting Basics

Greg Elmassian web site on large scale trains and garden railroads, cigars, and computers
elmassian.com elmassian.com

There's a lot of pages on LED basics. It helps to be familiar with Ohms law, V=IR, etc. If you don't learn the basics, stuff burns up.

Greg
 
Greg Elmassian said:
....OK, you CANNOT replace incandescent bulbs with LEDs......

um...what? well not just willy nilly of course.... I'm running off standard track voltage, not DCC, so as we both tested, the number boards get about 3.5 regulated volts at the lighting board. So, thanks to your links that refreshed my ohms law training from 40 years back, I do believe that the two number board lights could be replaced with LEDs like I have. white, 3.3 volt typical, 25ma current and a resistor that is a whopping 8.2 ohm 1/8 watt (oh lets double it to be a 1/4 watt) right? The two bulbs are in parallel, not series, so treat each one the same way. I was thinking of facing them backward and building a styrene reflector to avoid the hot spot effect on the number boards.

By the by...... The LED lighting basic page is pretty spot on and a good reminder of the basics for these things. I did a drawing for my reference on this lighting board.
Click to expand...
 

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I meant in the pull out an incandescent bulb and put in a bare led. one for one swap. Sorry, I should have been more explicit.

You need a dropping resistor (dumb name but that is what the industry calls it)

Of course you can replace incandescents with LEDs doing the right engineering...

Yes, I will be replacing the LEDs in all 11 of my F3's but want a good solution for the number boards... may make a small board that will let me mount SMD's and probably put them all in series to cut back the dropping resistor size.

With a constant 24v available, it makes sense to put as many in series as possible.

Some of the SMD LEDs have almost a 180 degree dispersion angle, and as you noted, you do not need a lot of brightness.

Greg
 
So here's another question. Greg, you have a bunch of these F3's. Do they all have standard LGB type couplers between the A & B Units? Or, does anyone use a fixed draw bar type of link between the units? Also, I found that if I left those motor screws hanging out too far, they sometimes catch on the coupler centering spring wire. Not much clearance there. These motors were brand new from OnlyTrains although I suppose they could be old stock. Someone mentioned that newer motors do not have these gear lash adjustment screws. What source did any of you find motors from that did not have these screws?
 
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