Friday, January 17, 2014

TCS M1 in an older ConCor E8A

The first new installation of 2014 is going to be on a very old model.  In the mid 1980's Con-Cor started to offer a model of the EMD E8A with the mechanism made by Kato.  This model has no flywheels and a more primitive motor that what we have become used to with more current releases.  Many of these models were sold up to the time that Kato introduced their own E8 models in 1994 with a great mechanism that is still in use on current releases of that model.

For this one the frame is going to have to be modified to fit the decoder.  I sent mine to Aztec Manufacturing for precision milling. The Aztec part number is TM3006 and the charge to get this done is only $10.00 plus shipping.  To send the frame to Aztec, fully disassemble the locomotive, put all the small parts in a small plastic and the motor by itself in another small plastic bag for storage until the modified frame comes back.

Decoder wire lengths:

Black  =  4-1/8 inches            Red = 3-3/8 inches             White = 3-3/8 inches              
Blue = 3-1/8 inches               Gray = 2-3/8 inches             Orange = 2-3/8 inches
Yellow = not used

 It's always been my practice to never solder the motor wires from the decoder to the motor brush caps while they were installed on the motor.  Normally with all other installs, I remove the brush, spring, and caps.  Then solder the wires to the caps and then re-install everything into the motor.  On all other loco's I've worked on this works out fine as the caps or brush holders snap into the motor body.  On these ConCor locos the motor brush mount screws into the motor.  With the wires already attached, the wires end up getting very twisted.

This upside down photo shows the correct orientation of the motor and how close the the motor brush caps are to the frame.  The white motor magnet is facing down.

The motor brush contacts point away from the top part of the frame.  When assembled, they made contact with the lower parts of the frame assembly.

So my method for the ConCor cab diesels is this:  I first fully unscrew the mounts and remove them.  Then place a small amount of solder on the surface of the mount.  After it has cooled, I re-install the brush, spring, and the fiber washer and screw the assembly back into the motor with contact part not used.  I don't fully tighten it but leave it loose about 1/2 turn.  Then I solder the tinned motor wire to the spot where the solder is.  The fact that the mount is a little loose, the fiber washer, and the solder already being on the mount seem to keep the mount from getting hot enough to melt the plastic of the motor.  The angle of the wire needs to be pointed upward as shown in the photo below.

When the soldering is done and the brush caps rotated clockwise to a snug fit things should look like this, with the wires pointed upward.

When the motor is re-installed into the milled top part of the frame, the motor wires go up through the slots that are milled.  This view is of the left side of the mechanism with the mechanism upside down.

I have found that the trucks can short on the frame so I add short lengths cut from .010 x .125 strip polystyrene to the areas of the trucks shown in this photo.  The polystyrene strip is held in place with Tap Plastics E6000 adhesive.

With the decoder wires laid out side by side they fit neatly into the milled groove on the top of the frame.  The yellow wire is not used but I keep some length on it in case it needs to be used later.

This photo shows how I connect the decoder input wires to the frame.

On the red wire I used a motor brush contact from a Kato motor to attach the red wire.

On the black wire because the screw is so close to the top part of the frame I did not use any ring.  Instead I just made a loop at the end of the black wire.

To upgrade the lighting to bright white LED first bend the leads so that they will fit around the rasied center part at the end of the top frame.

Place the heat shrink over the wires and solder the resistor to the lead with the smaller element.  Then attach the blue wire to the resistor and the white wires to the lead of the larger element.

This photo shows how the LED assembly fits into the area where the original light bulb was.  It may be necessary to flatten the ridges on the top and bottom of the LED.  The heat shrink will prevent anything from shorting on the frame.  This assembly can be secured with Walther Goo, Tap Plastics E6000 or other similar adhesive.

The model origionally came with black electrical tape over the headlight area to keep the light from shining unrealistically in the cab windows.

I did not see a better way to do it so I did the same thing.  The front edge of the tape should be even with the front edge of  the top frame and the LED.

The shell normally fits rather loosely on the frame so the electrical tape may make the fit more snug on the front end but it should fit.

The fuel tank clips into the shell at two spots on each side and that is what keeps the shell on.

The light should come out brightly on the top large headlight and more dimly on the bottom headlight and the number boards similar to this photo.