Roundhouse 0-6-0 vs DCC/Sound

[Schraddel]

Hello Matt!




Do you mean this engine? This is the later version with plastic body.


I own an really very old all diecast model too. The gear ratio of the diecast is 1:35 and for the plastic is 1:70. As delivered both have open frame Pittmann motors.

The prototype was, i am not a SP crack, a Southern Pacific switcher built by ALCO. It must be an older series with inner Stephenson valve gear and slide valves.
The plastic shelled model was those which i rebuilt to modern standards.
In short terms technically:
- remove open frame motor, it is a decoder killer
- replace it with an coreless coil motor (Faulhaber, Maxon, Escap, etc.)
- make a new motor cradle, the motor could be mounted horizontal and can simple glued onto cradle and frame
- make shure the gear mesh will be correct. The trick with a piece of thin paper stripe between worm and wormgear will work well here.
- if the loco will be run with DCC only, a flywheel is not really necessary
- NO CHANCE to current pick up problems!
- for this polarity of loco and tender should be the same
- make wipers for loco wheels, i did it for first and second axle wheels
- make wipers for all tender wheels, don't let spoil your switching fun by problems with bad pick up
- for lighting purposes i mounted 3mm warm-whithe LEDs and the necessary resitors for each LED
- loco and tender are permanently coupled
- at least 6 wires are connecting loco and tender: 2 for current pick up, 2 for motor, 2 for LED
- build a NMRA 8-pin socket into the tender so so can choose the decoder you want and replace in an easy manner
- insulated Kadee coupler boxes

How i have done that:


Loco pick ups.


Tender pick ups.



Inside of the tender. My Roundhouse 0-6-0 has no sound, so this brass tender of similar seize is an example.
A Tsunami 750 Small Steam decoder, a 3/4" speaker and the corresponding baffle kit. At the right side in this photo is the NMRA 8-pin socket and plug. I wrapped it with tape because an all brass environment is prone for short circuits
Left there is in this case a mini socket with 12 poles. Only 7 are used for connection to the loco.This may not be necessary if loco and tender are permanently coupled.
Here was enough space to make a small baffle with low profile and mount the decoder atop.

For optical look.
A lot you can see on the photos.
As the coreless coil motor is much smaller as the open frame pendant, it was possible the make an cab interior:
- the part of the boiler reaching into the cab
- boiler backhead
- cab floor
- fire box sides to hide motor and close the gap between firebox and frame
- bridge between loco and tender
All was simply made out of styrene sheet. Even the open cab doors were made out of it.
This was my first attempt to rebuilt an US loco. Simply because there are no plstic or die cast models of those older switchers on the market.
Big steamers, no problem, nearly every well known model was realized in plastic.
But small switchers? No Sir, only the Roundhouse or you have to go into the brass market.
So it was my choose to rebuilt this really antique Roundhouse model.

Further optical improvements:
It is your choice how much "brassified" you will go until you are satisfied.
In my case here are virtually no lost wax parts. I reamed my scratch box and recycled everthing suitable.
Done:
- brake shoes
- frame structure
- brake cylinders
- cooling coil, soldered by do it yourself
- air tanks
- roof hatch
- extended cab roof
- grab irons and hand rails
- check valves (scratch built)
- plumbing out of brass wire
- converting the oil bunker to coal bunker
- self made front and rear lights, aluminium tube with 3mm LEDs inside and plastic ends.

At least it was a low budget rebuilt.

Was i satisfied?
Yes, it is a real joy to do switching duties with this loco. The Faulhaber motor with flywheel in connection with the 70:1 gear did not and under no circumstances exceed the yard limit. An ESU Lokpilot Basic is fitted with the CV 3 (acceleration rate) set on maximum and the CV 4 (brake rate) also to an high grade.
Watch the loco accelerating from standing to max. speed in about 40 seconds. And the max. speed is yard limit 15mph (CV 5 is set at maximum)
Those guy who are accoustomed to toy train acceleration (o - 100 mph in immediateley) get really nuts with this little engine.
This is only what for gourmets.

Hope i could help you.

Lutz

Edit: Orthography