TCS Z2 in an older Atlas RS11

This is an old engine without the LED lights, flywheels, low friction trucks, or Micro-Trains ready coupler pockets that we have become accustomed to.  At about the time DCC started to catch on with N scalers in the early 1990's, this was a very common mechanism that was used on several models made for Atlas by Kato in the mid to late 1980's.   They do have a good motor, and with a DCC decoder momentum can be programmed to help make up for the lack of flywheels.

First step is to take the engine apart.  Getting the shell off is the hardest part.  Here's the trick.  First remove the cab to expose the catches that hold the shell to the frame.







Once the cab is off, the main part of the shell can be easily removed as shown in this photo.







This photo shows all of the parts after this RS11 has been dis-assembled.

This mechanism is almost identical for the Kato made Atlas RS3, RS11, RSD4/5, RSD12, GP7, and GP9.





Here are the lengths that I cut the decoder wires to.

2" - White
1-7/8" - Red & Black
1-3/4" - Orange
1-1/4" - Gray
7/8" - Yellow & Blue


This photo shows the decoder wires solder to the modified light boards and the motor brush caps.


The next two photos show the details of the light boards.

The PC boards are the same as the common Kato 77A board.  It's just that these have a light bulb and a diode instead of a LED and resistor.  The directional lighting will be determined by the decoder so the diodes are not needed.

The red and black wires from the decoder will make their connection to the frame from this board.




On the rear light board I cut off the tabs with a Dermal tool, removed the diode and soldered the blue and yellow wires from the decoder to the light.  Polarity will not matter with the light bulb.  A second blue wire was run between this board and the front board.










Re-install the brush caps with the brushes and springs on the motor.  Then place the motor assembly into the left side frame as shown in this photo.  This one did not have any separate worm gears or bushings, it was all attached to the motor.










Here is the completed DCC mechanism.  As you can see, there is lots of room for the decoder.  Any of the small wired N or Z scale decoders could fit in this space.



Finishing Touch

These older engines had truck mounted Rapido couplers with big openings on the pilots.

Micro-Trains made pilot conversion kits and these are still available.  For the RS11 look for Micro-Trains part number 1150.

TCS Z2 in a Life Like C-Liner

We start a new year of installing DCC decoders in N scale locomotives.  This year will be almost all new material as I think I've used almost all the old material I once had on the nscalestation web site. 

First up will be the Life Like C-Liner

I sent the frames to Aztec Mfg for milling.  This photo shows what is removed from the frame.  Because of the way the motor mounts into the frame with no plastic saddle, the space around the motor is tight and it's important to have the spaces milled around the motor so the brush caps don't touch and wires don't get pinched.


Just like I do with Kato F units, I take the extra step to drill and tap holes for size 2-56 screws that will be used to attach the decoder wires securely to the frame.  This would be a requirement on the B's anyway because there is no light board so I just do it for both A's and B's.


In this case I am using a TCS Z2 but any of the small decoders available today should fit in the space provided.

The wires are cut to the lengths indicated in this photo.  Then the brush cap are removed from the motor and the orange and gray wires soldered to those.  The motor brush contacts that are removed with the brush caps and then soldered to the red and black wires.  These will be secured by the screws to the frame to provide a reliable connection.










This step is done on A units only.  With a Dermal motor tool and a cutoff wheel, I remove the circuit traces that could connect the board to the frame.  Then I also make a notch in the front edge of the board that the blue and white wires pass through.  The blue and white wires are then soldered to the board as shown in this photo.  On this one I kept the light stock light bulb so a resistor is not needed.



After re-installing the motor brushes into the motor, the motor, gears, and bushings are all re-installed into the right side frame as shown in this photo.  Take care that the orange wire is in the channel and not being pinched between the motor and frame.  This model has a spacer with an odd shape that goes on the front.  Notice the orientation of the spacer.

Install the left side frame and install the nuts and screws.  Then use the 2-56 x 1/4" screws to secure the red wire to the right side frame and the black wire to the left side frame.





This is the completed mechanism for a C-Liner A.  Double stick tape is used to secure the decoder and wires. Test run the mechanism then if satisfied with the way it runs, install the shell. The shell on this model goes on straight down so that ribs inside the shell fit into slots on each side of the frame.

DZ123 in an older Life Like E8

This is another of the installations I had on the old web site which first appeared in December of 2003.  The engine used in this example was an E8A but this method would also apply to many of the older Life Like cab diesels that had a plastic frame and 2 weights over the axles.  The DZ123 decoder shown in this post is no longer made but any of today's small decoders would work very well. 

After removing the locomotive shell and rear weight, remove enough of the top of the rear weight the entire length for the decoder to fit in. There should be a ridge left on each side. This metal is not really hard and I do this with a hand file in about 15 minutes.

Next, file a slot up at an angle from the bottom front corner to the top at about 1/2 inch from the front. Then file a slot across the top to connect the angled

slot with the area removed for the decoder. Do this on both sides. This will be the channels for the wires.
There are long wheel contact wipers that run the length of the plastic frame. You will need to remove all the existing connections to these.

Be very careful not to use too hot of a soldering iron. I recommend the use of locking tweezers to act as a heat sink on the motor contact lugs.
The decoder and wires can be secured in place using a small amount of Wathers Goo.

The black, blue, & gray wires go to the left and the red, orange, & white wires go to the right. Re-install the rear weight and plastic retaining clip.
Connect the orange wire to the top motor contact and the gray wire to the bottom. Use a small piece of .010 styrene to insulate the contact strip from the motor connection.
 
Solder the red wire to the right contact strip and the black wire to the left contact strip.
 
 
 
 
The white and blue wires get run all the way to the front up under the front weight and up the slots to be connected to the light.  In this example I had used the original light bulb but an LED could also be used with a resistor placed in series.
 
After checking all of the wires are clear of moving parts and that the flywheels are turning freely, the mechanism is ready to test run.

TCS Z2 in an Atlas GP40

The older version of the Atlas GP40 did not have any provision for a board type decoder.  The sure fire way to get a wired decoder into one of these is get the frame milled by Aztec Manufacturing.  I've done many of those and they work out fine but this time I wanted to do something different.

Here is a look at the stock GP40 mechanism.  Notice that the two LED boards are put in differently.  They are actually different boards.  There is room under the rear LED board for a small decoder such as the TCS Z2 if the LED itself was not in the way.



These are the modifications I made to the right frame half.  I found that without the slot for the wires on the top of the frame, the shell was not resting square on the frame.






This photo shows a side by side comparison of the original rear board and the one I made from a shorter board from another Atlas engine. The SMD LED is wired to the board with magnet wire and hangs over the end of the board. It is now clear to leave enough room for the decoder and sticks out no more than the original board did.


Both circuit traces to the frame contacts are cut so that this is isolated from the frame.  The yellow and blue wires will get soldered to the LED and resistor on this board.  On this board rather than drill a hole I made the existing opening longer so all the decoder wires could go through the opening.




The Z2 decoder wires are cut to the following lengths:

Gray = 2"
Orange = 1-1/2"
Yellow & Blue = 7/8"
Red, Black, & White = 2-3/4"



On the front LED board a hole needs to be drilled at the location shown in this photo.  The black and white wires are connected as shown.

The circuit trace gets cut the the same
location as is commonly done.  The red wire goes through the hole and is soldered at the point shown in this photo.  With this board being component side up this will place the red wire on the right side of the locomotive.

As I do with many installations I have filed a groove into the right side of the motor to contain the gray motor wire and secure it with a tiny amount of Walthers Goo.

Here is the completed assembly before re-installing the shell.  The wires will lay in the groove and can be secured with scotch tape. 





I found that the best way to get the shell back on was to follow the steps that are in this photo.  The important thing is that the shell is seated properly on the frame so that the body mounted couplers are at the correct height.

TCS M1 in an Atlas SD50

The engine that I happen to be using in this post is an SD50 but the mechanism is the same for the SD60 and SD60M.  Besides the TCS M1 decoder used here, any similar sized decoder would also work.


Today's small DCC decoders as well as the design of this popular model make it possible to easily install a wired decoder a less expensive alternate to the board type decoders that are made for these models.  No frame modifications are needed.


After dis-assembling the loco mechanism, make the modifications shown in this photo.  The hole is on the long hood end of the PC board which has the longer wide area.  Wire thickness may be different for each manufacturer of decoder so size hole for the decoder you are using.

Bright white LED's were added on later releases of these models and the PC boards were re-designed.  There is an extra part on these boards labeled C1 that will not be needed in a DCC engine and this should be removed.  If you have one of the older versions with the yellow LED's and want to replace them with bright white LED's now is the time to do it.

Guide all of the decoders wires through the hole from the bottom of the board.  Attach the decoder to the bottom of the board with Walthers Goo.


Stretch out each decoder to the point that they will be attached to on the board and cut them about 1/4 inch beyond that.  The gray and orange wires will be attached to the motor and I use the line shown on the photo as a length guide for them.  This gives a little slack in the wires to work with.
In this photo the red, black, white, and yellow wires have been soldered to the board.  The scrap piece of the blue wire gets used to connect the front LED.
Study this photo closely.

Trim the motor brush tabs to be even with the top of the motor.  Guide the orange wire around the right side of the board and the gray wire around the left side and through the motor saddle.


Place a 1/4" length of 3/64" heat shrink tubing over the end of each wire.  Solder the orange wire to the right motor brush tab and the gray wire to the left motor brush tap.  Carefully heat the heat shrink tubing then place the motor saddle over the motor from the left side.  To make this operation easier is why the length of the orange and gray wires were left as long as they are.

Install the motor, board, and worm gears into the right frame.  The fit for the board should be snug to have good contact with the frame.  Then re-assemble the left frame, trucks, and fuel tank, then it's ready for a test run.  The left frame should also be a snug fit with the board.
The original paint on many of these models won't block of light of the bright white LED's and it will glow through.  I often paint the inside of the shell around ends with Floquil Old Silver.  It also helps to use the same paint around the LED's leaving just the end clear for light to shine through.

TCS Z2 in a Life Like SW9/1200

The Life Like SW9/1200 has always been one of the more challenging N Scale locomotive to get a decoder into.  No decoder has ever been made specifically for this model so it's been up to the modeler to fit in a wired decoder.  I've done a number of these engines and over the years I updated my technique.  What is shown below is the most reliable method that I have found.

Start by removing the fuel tank.  Then each of the trucks can be removed by turning them as shown.  Be careful not to bend the contacts that are attached to the body.


Next, remove the cab shell after unplugging the center hand rails from the cab.  The heavy steel weight may come off as well and that is OK.

Some may feel that inside the cab would be the obvious place to put a decoder.  I don't agree with that approach because this is where most of the weight is in this small engine.   I have tested these with just the heavy steel weight removed and found that the engine lost much of it's traction and pulling power.

It is important to remove the shell without damaging those contacts that are attached to it.  I made up a set of shims from .005 brass sheet.  These are slipped between the frame and the body to prevent the contacts from catching on the frame.

Slip the shims carefully between the frame and the contacts where the contacts go between the frame and the body.

Once the shims are in place, the frame can be separated from the body by pressing the exposed part of the frame down as shown in this photo.

Once the shell and the frame have been separated, disassemble the frame to the point shown here.

Remove the LED and the resistor from the little PC board.

Cut the Train Control Systems Z2 decoder's wires to the following lengths:

 
Gray = 1-1/2 inch
Orange = 1-1/8 inch
All others = 1/2 inch

Strip 1/16 inch from the ends and then tin the ends of the Red, Black, Orange, and Gray wires. Remove the LED and resistor from the circuit board. Solder the red and black wires of the decoder to the points on the circuit board shown in this photo.

Then the decoder is attached to the PC board with a drop of Wathers Goo.  It is positioned so that it is in the spot where the LED was.  In this photo an original LED board is shown next to the board with a decoder mounted on it for comparison.  The decoder is longer than the LED but is narrow enough to fit between the frame.

The Goo will need 12 to 24 hours to set and it's best to use a clamp of some sort to hold the position.

Once the Goo has set, the decoder / PC board should look like the one in the bottom of this photo.  Remove the motor from the plastic saddle and then remove the brush contact clips.  Cut them down to the shape shown in the photo and solder the gray and orange wires to them.  Remember the orientation of the motor, the hole is towards the top.

With a jewelers file cut a groove down the left side of the motor just large enough to fit the orange wire into.

Then clip the orange wire to the top brush holder, and the gray wire to the bottom brush holder.







Lay the gray wire in the groove and wrap Kapton tape around the bottom of the motor so that it is covering the bottom brush holder and ends at the top of the motor on each side, which holds the gray wire in the groove.

Install the motor back in it's plastic saddle and then the frame can be re-assembled.  Plug the LED board into it original spot.  With a toothpick place a small amount of Goo between the motor and the plastic motor saddle on each side of the motor.  Let it get tacky then press the motor wires into that spot.

The short white, yellow, and blue wires can be secured the same way as shown in the photo or they can be just cut off.  I like to keep any unused wires on a decoder available in case they can be used in the future.  As an example, I have re-used several decoders  that had burned out motor outputs as lighting function decoders.

Almost done:

Check that the flywheel turns freely.  Then test the mechanism by attaching alligator clips between a DCC source and each side of the frame.  If that test good, then re-install the shell, the shims are not needed to re-install it.  Install the trucks and fuel tank, then test again on the track.  If that test good then re-install the weight and the cab and re-install the hand rails. 

Add terminal strips to DCC Specialities PSX-1

OK, so this is not exactly a decoder install.  But I found that I really like these solid state DCC circuit breakers and figured anyone who was into DCC in any scale might benefit from this information.

This is a great little unit for setting up power districts on a larger layout.  It's a solid state circuit breaker that will trip when there is a short on the track and then clear itself when the short is cleared.  The basic hookup is real easy and there are also options on the board for the following:

• Track power on remote LED
• Track shorted remote LED,
• Block occupied input
• Block occupied remote LED

In my application I was installing 6 of these into a portable DCC power unit for a modular layout, that might be another post sometime.


The board comes with the green terminal strips on the ends for the DCC in and out but nothing for the other external connections I wanted to use.  I did not want to just solder the wires to the holes and the instruction sheet only says "Available from your dealer".



The spacing between the holes on the board for J4, J5, J6, J7, & J11 I thought was somewhat uncommon at 3.5mm but I was able to find a perfect fit.  Because all of the holes are in even numbers and the functions connections in pairs, I decided to use a 2 position terminal strip.  This type of terminal strip can be mechanically linked together to form a larger terminal strip as needed. 

I wanted to use the optional connections for track power ON and track shorted remote LEDs but the terminal strips I found will work for any of the external connections related to any of the optional functions.




Source:  Digi-key Corp.
              701 Brooks Ave. South
              P.O. Box 677
              Thief River Falls, MN 56701-0677
              http://www.digi-key.com/

Here is the information for the terminal strips.  It is actually cheaper to just get the 2 position ones and link them together as needed to make bigger terminal strips.

 Digi-Key Part #      Description                                                 Cost
281-1402-ND          Weidmuller 4-pos 3.5mm pitch terminal          1.89
281-1400-ND          Weidmuller 2-pos 3.5mm pitch terminal            .89

 Here is a link to the DCC Specialities instruction for the PSX-1:  http://dccspecialties.com/products/pdf/man_psx1.pdf