ALCO from ALCO or another 0-8-0

[Schraddel]

Hello!

Here is another adventure in brass. A few weeks ago i purchased another USRA 0-8-0 for my layout:






This was the state as is when i get her. The only thing i did was removing the obsolete pilot deck stancions as USRA 0-8-0 never had them.
For an model made in the 1970's it is astoningly well detailed. It must be one of the first Korean brass models.


The lacking of an boiler backhead allows to see the open frame motor.
Here you have also a look to the new made current pick ups.



The rather crude open frame motor. One inch of wire represents the whole electricity. And there is a small gearbox made of brass sheet.

The first attempt:

Removing the old motor and replacing it by an Faulhaber coreless coil motor.
Then replace this piece of rubber or not-so-soft-silicone with a real universal joint drive shaft.
Making an torque lever out of hard brass sheet.
Now the wiring was done, i will show this lateron.

But first:
Contemporary wiring and adding 12V DC to the motor terminals.
Rrrrrrr...
Scheiße. (English translation will be censored automatic by forum software)
As you can see in the last photo the gearbox input shaft (worm shaft) is slightly rusted. This enlarges the bore of the worm shaft creating a bad mesh between worm and worm gear and resulting a noisy gear.
The gear box is made of plain brass sheet, soldered together and is an somewhat sealed unit. Of course the bottom cover is screwed, but you can't get out the worm shaft and the also soldered bearings. Questionable quality.

The next thought was a replacement by an NWSL gearbox.
For an switcher and switching duties i choose the 36:1 variant with 0.3 module.
But alas, this was no simple drop in replacement.
First, the old brass sheet gearbox had a tight fit into the frame.
Second, the boiler above the gearbox is completely modeled and closed in this area.
Third, the gearbox has to be mounted in an angle to keep the universal joint as near as possible to an straight line.
Fourth, the torque arm has to be bend in a strange shape to keep clear of the underside of the boiler.
Fifth, all axles are sprung and the torque arm must under all circumstances kept clear off the universal joints.
Sixt, it should be still a simple procedure to remove the body without a snake's nest of electrical wires.


At first is modified my puller to accept 3mm axles. All wheelsets were out of tolerance according the NMRA standards.
The replacement of the axle gear was also done with this device. And don't forget quartering.


The NWSL gearbox would'nt fit as out of the package.
Grinding down the gearbox case.
Grinding down a frame traverse to make space for the gearbox.
Grinding down the valve gear mounting plate.
Making a new torque arm, bending ist in strange shape to clear all narows.
Grinding down the mounting screw on the gear box for the torque arm.
At least grinding some trench into the boilers underside.


It is tight, but it can made it's necessary movements caused by sprung action.


Still some grinding: The original NWSL bottom gear cover did not fit here because it is too bulky. So i had to use the old gear cover made ot of sheet metal again. Due to the relative small driver wheel diameter i had to remove some brass here too to keep the gear box clear of grade crossings and pavement when street running.
A Kadee Coupler box was mounted afte some :mrgreen: grinding of the original casted brass coupler box. The Kadee box was also shortened at the rear end. The whisker #158 coupler made that possible.

Now the electrics.

Here i tried something new.
On evilbay i found this sub miniature male and female plugs. They have 2 x 6 poles, too much for the most loco to tender connections and too stiff.
So i reduced them to 7 poles:
1: rail right
2: rails left
3: motor
4: motor
5: common
6: front light
7: cab light ( planned here for later when cab interior is complete)

I soldered a wire holder on the rear frame to keep the wires together. For optical reasons only black wires were used.
The loco tender lash was bent to Z-shape here and is no more insulated because loco and tender have the same polarity now.

The tneder was threatened similar like this one:



Got an NMRA 8-pole socket, an separate plug for the back up light.
The light casings front and rear were drilled with an 3.2mm drill.
3mm warm white LEDs got one layer of the German equivalent of Kapton tape were inserted. Each LED got it's own 1.2 Kohm resistance.


Fitting the case:

No, it would not fit straight.

DANGER!
EXTREME TERROR SAWING!
Do not read further if you are anxious.
Or the EMS unit stands directly in front of your door ready to make an emergency depart.



























































As the Faulhaber, a 1724 type, is a little more wide than the old open frame, i had to cut off two stripes from the underside of the firebox.
Now the body will fit.


The missing boiler backhead was temporarly replaced by an simple plain brass sheet glued with 2 drops of CA.
You can also see the electrical connections between loco an tender. The plug has still 12 poles, but the wires are reduced to 7 ones.
The female was glued onto the tender bottom.


The wage of the work is an very smooth running brass 0-8-0.
As smooth as you can expect with an Faulhaber coreless coil motor and an NWSL gearbox.
Even in analog mode it is impssible to exceed yard limit speeds.
I plugged an ESU Lopi V4.0 in and after optimizing the CV parameters it runs still smoother.

The complete work is still not done here:
- bridge between loco and tender
- complete boiler backhead and cab interior details
- some details at the exterior
- a load of coal
- painting
- decalling

Lutz