Current Bachmann "Blue Box" FTA offering and motor replacement.

[jbrock27]

Good Morning All

Does anyone know if I can replace the existing motor in the above referenced unit with the one sold on this site that is listed for the F7 model, that has the brass flywheels?  I ask bc I bought my son the above for Christmas and it runs great except for having a lot of trouble going up an AHM standard trestle  grade with more than 2 cars attached.  This is the only loco in our fleet that has this problem and in looking at the motor, I see it is just a can motor with no flywheels.  I have added all the extra weight I can and my thought was a flywheel motor would have more torque than the standard issued motor thay is in this loco.
Thank you for the help.

-Jim

[Doneldon]

jb-

Not knowing exactly what loco you have makes it hard for me to answer your question. I can say that it's easy to get grades too steep for entry-level locomotives. Anything steeper than 2% (two-inch rise in 100 inches of track (about 11 sections) is considered very steep and will undoubtedly challenge your motive power.

It's not necessarily true that your loco is the problem because other locos seem to handle the grade with ease. Like cars and people,
some are built for speed, some for power and some, like me, just for old-fashioned good looks.

                                                                                                                                                  -- D

[Stephen D. Richards]

You have several options here.  Without knowing more info on your loco, I would check with Joe DeLia at A-line/Proto Power West for either motor and flywheels or just the flywheels!  Alliance Locomotive in Ohio also has some outstanding motors and flywheels.  The have the Helix Humper!  But keep in mind that the gearing may need changed as well for it to pull well.  The flywheels help considerable.  I have seen much improvement just putting on flywheels on the Bachmann motor.  It is a very good can motor!  Hope that helps some.  Stephen

[jbrock27]

Thank you both for taking the time to send your replies.  The locomotive I bought for my son, is Bachmann's current Blue Box locomotive, FTA model.  It has a can motor w/o the flywheels.  The heart of my question is, can the shell from this model be placed on either a Bachmann Spectrum or a Bachmann Plus F7 or FTA chasis?

Thanks very much for the help.

[jward]

probably not. the ft is slightly shorter than the f7.

[jbrock27]

Jward-do you mean in real life or HO life?

[jward]

they are scale models, therefore both.

on this forum, others have mentioned repowering f7s with an ft drive, and that the ft drive was shorter than the f7 body.


btw, the reason the other f units were longer than the ft is due to the fact that the ft was designed to be coupled to its b unit by a drawbar not a regular coupler. the drawbar took up alot less space than a standard coupler. when certain railroads ordered their fts with couplers on both ends, EMD had to use a modified coupler which draped over the rear axle. this design flaw was corrected on later models of f unit.

[jbrock27]

Thanks.

Do you know where I can find the re motoring topic you mentioned, in other sections of this forum?

And btw, I think we both know that to scale in the real world, does not always translate to true scaled features in the HO world; at least not from what I have read about complaints about how Blue Box Athearns are too wide and how flawed their noses are on their models like the SD45.

[jward]

on older tooling such as the athearn blue box, compromises had to be made to allow the motor to fit inside the body. to-day modellers are much more discernign about accuracy, and motors are smaller.

the ft seems to be newer tooling, thus it is much more accurate than something from the 1960s.

as for the post i am not sure what thread it is under, but it has come up several times in the past.

[jbrock27]

As a follow up to this Thread; it is not true that a Standard Line Bachmann FTA shell will not fit on a Bachmann Plus F7 chassis.  I found the fit perfect, all that has to be done is reducing the number of plastic posts for screws on the FTA shell from 4 to 2 to fit on the F7 Bachmann Plus chassis.

Also, the AHM trestle set, waaaayyy to steep a grade, gotta be over 3%.  That was a large part of the problem.  The Atlas pier set, has a  much better, manageable grade.

[on30gn15]

going up an AHM standard trestle  grade with more than 2 cars attached

That is the root of the issue, motor with or without flywheels is of minor to negligible to zero relevance.

A 4% grade is getting pretty steep and really affects the ability of an engine to haul a train a lot. I have seen some trestle sets that worked out to be nearly 8%; some locos made it to the top and others didn't.

http://www.nmra.org/beginner/track

By way of illustration, NP's big 2-8-8-2 mallet steam locos were rated to pull 4,000 tons on level track, and only around 600 tons on the 4% grade where they paralleled the MILW at one point.

Because of the limit of adhesion of metal wheels on metal rails, trains both real and model lose pulling capacity fast on grades. That 4% grade is a rise of 4 feet/meters in a run of 100 feet/meters. Specific names of units isn't all that relevant since it is the proportion between rise and run, whatever the name the values go by.

In general model trains can pull less on the flat and a little bit more on grades than real trains can.

[jbrock27]

Miss me making this statement, earlier today, recognizing same?

Also, the AHM trestle set, waaaayyy to steep a grade, gotta be over 3%.  That was a large part of the problem.

That said, not all locos (makes) are created equal

[jbrock27]

With the change in grade, happy to report the FTA can easily haul at least 3 cars .  I also removed all the extra Euro hardware; caps etc. from the motor and it runs at a lower starting voltage.

[Len]

There's a trick with the AHM (and Tyco) trestle sets to reduce the grade to a reasonable slope. Use two sets.

Take one set, and measure the height difference between two adjacent piers. Make a bunch of shims half the thickness of the height difference, and at least as wide and long as the pier base. Combine the sets, with a shim under every other pier.

Calling one set 'A', and the other 'B', you should end up with:

A1 - B1+shim - A2 - B2+shim - A3 - B3+shim...and so on. This should bring the grade down to somewhere between 1.5 and 2 percent.

Len

[jbrock27]

There's a trick with the AHM (and Tyco) trestle sets to reduce the grade to a reasonable slope. Use two sets.

Len

Funny you should mention that now.  In fact, I did have and was using, 2 sets, just did not employ a shimming method.  Anyway, the Atlas piers still work and look better and are not as fragile.  It did recycle the trestles though.

I am still waiting for my abacus to arrive so I can employ your prior suggestion on how to use styrene to make the "ties in mid air" look disappear.