Tuesday, January 18, 2022

Casula Hobbies Z19 1954 - Modification of the Marker Lighting

My Casula Hobbies Z19 arrived a couple of days ago, a lovely little model and it runs really well. A big well done to Joe and his technical team.

Casula Hobbies Z19 1954 fresh out of the box

I had ordered 1957 but received 1954 for some reason, perhaps too many had ordered 1957 and I missed out. I don't mind though as 1954 is the same Baldwin tendered version with cut-out cab and cowcatcher. Given the COVID-19 situation, I wasn't up to taking it back or going to the Post Office to send it. Christine and I had our booster shots today and we won't be getting out and about until two weeks after.

I am not a fan of Loksound although I do have four Loksound 4 decoders in some steam locos. I decided that I would take the Z19 with the Loksound 5 sound option as I investigated the Loksound 5 Micro Next 18 decoder and determined that there were two extra power outputs that I could use to improve the marker lighting.

ESU LokSound 5 Micro DCC Next18 output diagram

It is obvious why the marker lights were set up the way they came as the soldering of the extra wires is perhaps not a great idea for a production model as it restricts the decoder from being a simple plug-in for the modeller who wants to add sound later.

Now, the exploded schematic of the model that is supplied in the box shows that there are four screws but they are mostly hidden beneath the ends of the front and rear bogies.

Warning, do not do what I did. I unscrewed the bogies at their pivots and then tried to move the bogies to clear the body mounting screws. The bogies have pickup wires through the tender floor and can't be moved far. I did manage to just clear the rear bogie to unscrew the rear body mounting screws but in trying this at the front a disconnected one of the bogie chains. Now, the chain is glued over a short small peg on the end of the bogie side frame and it was a nightmare glueing it back when I had finished.

The best way to access the tender body mounting screws is to carefully spread the bogie side frames and pop the axle out that is over each screw position. Don't bend the side frames out too far as the axle ends run in a metal inner frame for the electrical pickup.

Anyway, back to the reason for accessing the two extra outputs. The marker lights on the model are able to be switched on and off and are independent of the headlight(s). The model marker lights are designed to have white at the front and red at the rear when moving forward and the reverse of this when moving backwards. This is not prototypical when pulling a train as the red lights should be off.

Here is a photo of the underside of the Loksound 5 Micro Next18 decoder showing the additional output solder tabs which are AUX5 and AUX6. There are three other outputs but they are logic level and will not power a LED without some additional circuitry.

The underside of LokSound 5 Micro SCC Next18 decoder
showing the AUX5 and AUX6 outputs

The orientation of the decoder in the above photo is not the same as the ESU diagram as I decided to take the photo of the decoder in the same orientation as it is in the tender just flipped over.

In the following photos, I decided to use the number 3 output on the circuit board at the front and the number 2 output at the rear of the tender as they were easier to access with the soldering iron. These equated to the front and rear white marker light LEDs.

The white wire attached to Output 3 must be unsoldered from the board as it will be soldered to a 1KOhm 1/4 Watt resistor which has another piece of white wire soldered to it. This white wire is then soldered to the AUX5 tab on the decoder.

Output 3 white wire disconnection spot on circuit board

The yellow wire attached to the rear yellow surface mount LED will be unsoldered from the board at the R5/C8 connection in the lower-left corner next to the speaker. The photo below shows the yellow wire already unsoldered from the R5/C8 connection spot on the circuit board. I forgot to take a photo before I unsoldered the yellow wire.

Output 2 LED and  yellow wire disconnection spot on circuit board

The yellow wire is then soldered to a 1KOhm 1/4 Watt resistor which has another piece of yellow wire soldered to it. This yellow wire is then soldered to the AUX6 tab on the decoder. 

Please note that all white wire solder joints, yellow wire solder joints and resistor leads have 0.6mm heat shrink insulation tubing applied.

Extra marker light wiring and resistors in place

After re-wiring, I now have each pair of white and red marker lights on a separate function button. So the marker lights are a bit more prototypical.

  • White marker lights at the front when and red markers on the tender when running light (locomotive by itself). The reverse when running tender first of course.
  • White marker lights at the front when on a train and no red markers on the tender.
  • Red marker lights at both ends when shunting.

When testing the marker lights I found that if the red markers are on and you turn on the white markers then the white dominates the red and you can't even see a tinge of the red.

Once the re-wire was complete I weathered 1954 and added a crew.

I used two different greys, a darker and a lighter one and followed this with a light application of black pastel powder to the tender bogies as I felt that they were too light and clean. I then used some cream coloured pastel powder to add a spilt sand effect to the sandboxes area just in front of the cab on both sides. Finally, I added a very light application of rust coloured pastel powder to the lower half of the smokebox door.

Here is a link to a JMRI DecoderPro file I made for the Z19 default CVs. Before I did any of the above I read all the CVs into DecoderPro and also did my best to work out what sounds are on what function numbers (see the Function Labels tab in DecoderPro). I could be wrong for a couple of them so would be happy to be corrected.

EDIT: Here is a link to a just-released PDF document about the Casula Hobbies Z19 that includes the default function list.

One final note, I was disappointed to find that there is no short whistle for use when reversing, three short whistles. There is however a function button that will play four different long whistles, very strange!

Some whistle files can be programmed to allow a short or long whistle to be played depending on how long the whistle button is pressed but this isn't one.

I hope that the LokProgrammer sound file for the Z19 will be made available as that missing short whistle is very annoying.

If the file is made available then I will have to borrow a LokProgrammer from a friend and add a short whistle.

Overall, once again I can only say congratulations Joe Calipari.


I received a comment question about the coal load and if I have any intention of doing something about it, here is my reply:

"The short answer is yes. The longer one is that I hope to do something about a keep-alive but there isn't much room in the tender. The model coal load is quite flat and it is removable, well I hope it isn't glued in too strongly.

My idea is to remove the plastic load and investigate how much room can be found with a 'taller' load. The keep-alive will have to be a homemade one as the supercapacitors may need to be spread around inside the tender and coal load.

Then there is the final issue.... I have to find my supply of coal. I have obviously put it somewhere other than where it was usually kept."