The problem with college students today is that 80% of them can't write properly and the other 30% can't do math.

Since the discussion has to do with good wheel-to-rail contact, then I offer my experience with it over the last 44 years:

1.  Humidity and oil on the rails collect dust, which, when combined, ultimately turns into the crud that wheels pick up.

2. Both metal wheels and plastic wheels equally pick up crud, although porous (sintered) metal wheels seem to collect it faster.

3. A wiper makes better contact to a rail-head than does a wheel tread.

4. Flywheels (either mechanical or electronic) work better than anything else at avoiding erratic operation; however, they will not start a locomotive that is not electrically in contact with the track.

5. Rail heads that are scratched during the cleaning process collect more dirt than those cleaned by chemicals or by wiping with a fine-grit pad.

6. Heavy locomotives do not stall as much as light-weight locomotives.

7. Brass rail tarnishes faster than nickel-silver rail.

8. More wheels electrically connected to the pickup system mean better contact.

9. Track wiring must be designed so that there are no dead spots (such as switch frogs) nor possibility of shorts (such as switch points of opposite polarity to the mating stock rail).


So, to keep my stuff running smoothly (and that it does), I do the following:

I run heavy, flywheel-equipped, wiper-equipped locomotives with all wheels wired for pickup on dry, nickel-silver track that has been cleaned with a low-abrasive cleaning pad in a room equipped with a big dehumidifier that includes a dust filter.

I avoid oiling my rolling stock journals unless they squeek, and, even then, very sparingly.

There is no miracle cure. I had to do all of the above (combined) to get smooth operation. Leave out one thing, and the contact chain is broken.


Morris

Make sure the plugs from the tender wires are pushed all the way (fully seated) into the mating connectors under the cab.

It's obviously an electrical problem. Take something like a toothpick and very carefully probe around the locomotive wheels, contacts and connectors until it jumps or otherwise moves. That'll pintpoint the problem and most-likely it is very easy to resolve.

You're correct...it'll probably take less effort to solve the problem than to return the locomotive to the servce department.

I'll bet some of you guys have trouble just opening the box the loco comes in.

7.2 volts is correct.

The trouble is with the trolley and you are correct about getting it repaired.

Use a DC voltmeter to check the voltage across the rails.

It's possible the power supply output voltage has degraded or there's some other fault in the electronics.

I think a thousand people each asking once for something would probably bring better response than one person asking a thousand times.

On straight DC, all engines should run in the same direction when on the same track, no matter which way the shell is on, or if it even has a shell or not.


In other words...

The mechanisms must all go the same way (follow each other as in a parade) on the same polarity; otherwise, there's something wrong with the wiring or the motor windings/terminals.

I don't have one in front of me in order to see the wiring, but you can check the following:

If the headlight is wired to the white (front headlight) and blue (common for functions)leads from the decoder, add the yellow (rear light) lead from the decoder (if it has one) to the white lead so that it will stay on in both directions.

Dear Al,


I just now took your advice and rotated the motor as you suggested.

The unit now runs in the correct direction.

Thanks for the solution!


Morris

I've got the same problem with the no. 81259 F7 A/B set.

One runs backwards and the motor can be neither repositioned nor rewired.

I'd like to view the solution to this problem, too.

Wow!

I gotta get me one of dem dare sticks that measures in thirds of an inch.

<grin>

Micro-Mark says they got 'em in stock.

http://www.ares-server.com/Ares/Ares.asp?MerchantID=RET01229&Action=Catalog&Type=Product&ID=84276

I just checked with Micro-Mark. They have them in stock.

Not yet shown on their web site. You have to call them.

1-800-225-1066


Morris

The turnout number describes the angle at which the rails cross at the frog:

In a no. 4 turnout, the rails are 1 foot apart at a distance 4 feet beyond the frog

In a no. 6 turnout, the rails are 1 foot apart at a distance 6 feet beyond the frog

In a no. 8 turnout, the rails are 1 foot apart at a distance 8 feet beyond the frog

and so on.

From this information, you can see that lower tunout numbers mean a larger angle at the frog.

Big locomotives require a higher turnout number, as do higher train speeds; otherwise, they are derailment prone.

The above defines turnouts with straight rails through the frog, as is most-often done on full-size railroads.

To match certain curved track sections for convenient layout design and construction in model form, some manufacturers fabricate turnouts with a curve through the frog. In those cases, the turnout may be specified as a radius of curvature, rather than a number.


Morris