Modeling Notes: Product Notes

Occasionally someone shares a handy tip related to a specific model that would be nice to keep around. This page will be the collection point for those.

MTH

F3 4-digit Address Calculator

Use this handy calculator to set the long, 4-digit address of the MTH F3 locomotives equipped with DCS ProtoSound 3.0 decoders. Type in a positive number between 0 and 9999 (usually matching your engine's road number), and press the Tab or Enter key to see the results in the two CV fields. Then program your engine's decoder with those two values. (source: MTH web site)

F3 Convert To Scale

Lee Rainey reports that one must pay close attention to the position of the axle bearings when replacing the wheels after converting them to "scale" wheels, because the "notched" vs. "flat" edges' positioning of the bearing has a noticeable affect on how the engine performs. If you have a non-powered A- or B-unit that doesn't roll smoothly, it is likely that the bearings weren't installed correctly after the conversion. So, make sure the flat part of the bearing rim is toward the body and the notch in the bearing rim is directly away from the body.

Also, like S-Helper Service engines before it, the MTH F3 engines, when converted from the hi-rail wheels to the scale ones, need to have their wheel contact wipers adjusted. When the scale wheels are installed, the wipers may not make contact, which will lead to the engine not getting enough contact with track power. Although this is a different model, the concept is shown in a photo on the webmaster's personal web site that conveys this issue (see the 7th photo on this web page).

Overland Models

4-8-4

A note from Rusty Rustermier:

"It appears that screws hold the driver springs in place on the GS-4 frame. The holes the screws go into are not threaded. Instead of threading the holes, Ajin drilled the holes oversize, put super glue into the hole, and then pushed the screw into the hole with the driver spring. Be aware when taking this model apart; clean too aggressively and the screw and spring may be hard to find again!"

Rex

Mechanical Diagrams

Freight Truck Assembly, 2-6-0 Mechanical Assembly, 2-6-0 and 0-6-0 Tender Assembly, 2-4-4T Mechanical Assembly, Product Ads, 1985 Parts List, 0-4-0 Mechanical Assembly (18-page PDF document).

S-Helper Service

General

Don Thompson mentioned that all of their wheelsets are double insulated. This includes locomotives, freight cars, cabooses, and tenders.

Don Thompson recalls that the Chinese factory used automotive paints on their freight cars. Brian Jackson reports that he has had success removing paint from a composite hopper using 91% isopropyl alcohol. He reported that he started seeing results in a few minutes, and large amounts of paint came off after about 30 minutes of soaking.

2-8-0

Don Thompson shared how to disassemble and re-assemble this engine. This is an advanced topic, so take care. "You need the 1.6mm wrench to remove the side rods from driver #4 (available from Dave's Twacks & Twains or Hoquat Hobbies). The delrin bottom chassis cover/brake hanger has flat head Phillips screws, and the two delrin injectors are a press fit and need to be detached. Once removed, you are exposing a flexible printed circuit board that brings power to the headlight, optical detector of the chuff count, smoke unit, and both rail pickups. This unplugs under the cab. When you lift out driver #4, do not forget that there are two phosphor bronze pick-up pins touching the back of the driver. They are spring-loaded and there are no replacements! As far as quartering the one driver, should you need to install a new gear, I would use a carbide scribe and scratch the axle end and driver so that you can line that up as you press the driver back on the axle."

Don Thompson warns to not plug DCC decoders into this engine without dealing with the headlights first. The headlights are 5-volt bulbs, and they will blow as soon as the decoder receives power (usually around 12 volts). One option is to consider replacing them with LEDs and a matching resistor.

Dave Held and Dan Vandermause both report that NWSL has the parts necessary to replace a broken gear in these locomotives. Remove the driver from the engine, and send it to NWSL to have them replace it for you for around $66 (includes postage in late 2016). If you are brave and have the tools and time to do the work yourself, then order the replacement gear (NWSL #2930-6) for $14.95 plus postage. Dan recommends that you order one for each 2-8-0 you have, just in case they develop this problem in the future and NWSL is out of them.

Wheel pickup is provided through the tender's 8 wheels, and through the engine's drivers 1 and 4. Drivers 2 and 3 do not have frame contact. Note that if a short-circuit happens, it is possible for the brass wires behind the wheels to curl away from the back of the wheels due to the heat of the current flow. This will cause the locomotive to stall out from time to time. The solution is to clean the residue from the wires, and re-bend the wires back such that they make contact with the backs of the wheels. If the wires are too far gone, replacements will need to be made (or bought), if they are not in the box.

F3

Don Thompson warns to not plug DCC decoders into this engine without dealing with the headlights first. The headlights are 5-volt bulbs, and they will blow as soon as the decoder receives power (usually around 12 volts). One option is to consider replacing them with LEDs and a matching resistor.

Bob Hogan did a product review of these engines in the November/December, 2001 issue of the S Gaugian magazine.

Don Thompson says that to remove the shell, remove the four corner screws, and then wiggle the shell. Put a small screwdriver through the back door on the top of the floor to release the rear of the shell first.

MU cables between these engines only synchronized the motor current; it has no effect on the sound of the engines.

Converting one or more engines with Locomatic factory-installed to a plain DC version requires the removal of the Locomatic unit and adding a DC-shorting plug to each of the engines. The MU cables are then no longer needed. Test each unit individually for proper starting direction (if running in a multiple-unit consist).

F7A

Don Thompson warns to not plug DCC decoders into this engine without dealing with the headlights first. The headlights are 5-volt bulbs, and they will blow as soon as the decoder receives power (usually around 12 volts). One option is to consider replacing them with LEDs and a matching resistor.

F7B

From Don Thompson: On the DC shorting plug, if you put your multimeter's probes on 4 and 8, you should get track voltage. If you put the probes on 1 and 5, you're connecting with the motor leads. There should be a continuity between 1 and 5.

NW2

The three wires coming out of the cab are: common, rear headlight, and cab light.

SW8

The three wires coming out of the cab are: common, rear headlight, and cab light.

SW9

The three wires coming out of the cab are: common, rear headlight, and cab light.

Two-bay Panel-sided Hopper

The S-Helper Service models were based on the Union Metal Products Co.'s pressed-steel panel-sided two-bay hopper cars. These were rated at 55 tons.

The NYC rebuilt 1,500 cars to have the extra carrying capacity of the side-panel hoppers. Both the PRR and the New Haven only rebuilt one such car. Other railroads, such as the Wabash, Frisco, and the CN rebuilt literally thousands of cars.

(source: NASG Dispatch, April 2003 issue)

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