Removing Trucks From Trix H12-44

[nkalanaga]

MY F units seemed to get better with use, and ran very nicely after 15 years.  The NWSL wheels do improve the FM, and seem to stay a little cleaner, at least on my track.  They weren't available when I was running my Fs, so I turned the flanges with a Dremel and needle file.  A pain, and a little fiddly, but they all came out well, and stayed on the track.

[Doug G.]

I finally bought one of these, after over 40 years, off ebay and it runs just like I remember my old late friend Emmet's Milwaukee unit did in 1974/75. Are you guys claiming jack-rabbit starting using straight DC? Mine creeps very nicely with my Tech II packs.

Anyway, the one I bought had the infamous Penn Central paint flaking off and where the paint came off, there was oil underneath. I think they forgot to clean the shells before painting them. The shell is now completely stripped of paint and the plastic is a real deep maroon color except for the cab roof which is black.

I ordered a Milwaukee shell for it and haven't decided what to do yet, paintwise, with the stripped shell

Doug

[nkalanaga]

Mine is also that maroon/brown plastic, as were the early Fs.  That seems to have been the usual plastic for MiniTrix locos.

[Doug G.]

You're right, it is actually more of a dark brown than a maroon. My F unit is unpainted Pennsy tuscan I don't know if all the Pennsy units were unpainted or if they actually painted some of them. Mine doesn't have a headlight either and I know they offered them both ways.

Doug

[Doug G.]

And here I am, at the age of 22, switching cars with Emmet's H-12-44 on his layout on March 1, 1975

[ Guests cannot view attachments ]

The FM can't really be seen but it is right in front of me with the string of cars with a white boxcar toward the camera.

Doug

[nkalanaga]

None of my Fs had headlights, although they all had mounting holes for them.  I put MV Products lenses in mine rather than try to fit a bulb.  They also had the translucent white window "glass", which looked worse than none at all, solidly glued in, so I never bothered changing it. 

The FM still has it, along with MV lenses in both ends.  The headlight in the cab works, and the MV lens has a hole drilled in the back so the light can show.  It also lights up part of the cab, typical of early N scale.  Definitely not a state-of-the-art model, but it runs, and it is an historic part of my layout.  I wonder how many of today's units will be running 45 years from now?

[Doug G.]

Oh yeah, I forgot to mention I moved the headlight to the front. I always thought it a bit silly for Trix to have put the bulb at the cab end. Maybe they thought that WAS the front!

I have also thought about putting a bulb in my F unit but haven't yet. As you said, there is a place for one and it would be relatively easy to add one. The bulbs appear to be the same ones used in Atlas' RoCo units from the seventies.

Doug

[nkalanaga]

I wouldn't be surprised if they thought the cab was the front, and it may have been, on some roads.  Also, there's more room there, which may have had something to do with it.

[atsf_arizona]

Main reason for the poor start is the low gearing used in the trucks. Installing a different motor won't help you much.

Marc

Marc or anyone,

Has anyone come up with a method for re-gearing the Minitrix H12-44 trucks?

[nkalanaga]

I doubt that there is one, short of installing a gearbox-equipped motor, and that would require gearboxes on both ends of the motor.  Those Minitrix trucks are virtually indestructible, but that also makes them very hard to modify.

[nstars]

John,

We haven't tried to regear it. Hans just built a new chassis. 

Marc

[nkalanaga]

That would work.  And you could keep the current worms and truck gears, just changing the motor, which would be simple.

[nstars]

That would work.  And you could keep the current worms and truck gears, just changing the motor, which would be simple.

Keeping the worm and the truck gears is not an option. You have to change those to improve the gear ratio and unfortunately that is what is needed.

Marc

[tehachapifan]

I don't really notice any issues related to gear ratio as far as loco speed goes. Is that what we're talking about regarding gear ratios or is it a gear meshing issue if changing to different worms? What I figured was going on with the higher voltage and somewhat jerky starts had to do with the 3 pole, non-skewed motor being in-between "cogs" so to speak. I've installed an old Atlas (fast) motor in mine (it was not a drop-in fit) as an experiment (with LL SW plastic worms, for now) and I now have much better slow speed and start control. However, I do notice increased noise that I believe may be due to the LL worms not meshing well with the Trix truck gears. Using the original Trix worms does not appear to be an option as the motor shaft on the Trix motor appears much smaller in diameter than the Atlas motor shaft. I am going to try some Kato brass worms next to see if that helps with the noise. If not, I will convert back to the Trix motor as it worked very well otherwise.

[nkalanaga]

Marc:  If all you want to change is the truck gear ratio, you're right.  But if you want to change the total gear ratio, between the motor and the wheels, a gearbox at the motor would do the same thing.  Either way will change the ratio between motor and wheel RPMs. 

In the Minitrix model, simply installing a modern motor would make a difference.  The models run nicely, but tend to start abruptly, due to the primitive 3-pole motors. 

If the worm shaft is smaller than the new motor shaft a good machinist should be able to bore it out.  If you don't have the tools to do it you might be able to find a jeweler who can, for a modest fee.  It wouldn't take more than a few minutes on a small lathe. 

Or, as an alternative, you could have the motor shaft turned down to fit the worm, which would be even easier.  That could be done in a lathe, drill press, milling machine, or even a portable drill clamped to the work table, using a small flat file.  It would have the advantage that, if it failed, for whatever reason, you could buy a new motor.  Finding a new worm might be hard.