Step One

I needed one of these little critters for a major re-work of one of my yard areas.  Some of the sections are a little tight lengthwise for an MP15 or NW2 so I figured a Trackmobile might be a good answer for moving cars around and reconfiguring incoming and outbound trains.

I like all of my locos to have working lights, problem is Broadway make these in DCC versions but don’t put lights in them.  As information on the installed decoder wasn’t available, I decided to purchase a DC version and see if I could put my own decoder (Digitrax DZ123) and some lights in it.

Step one was to get the thing apart.  As with many manufacturers, Broadway seem reluctant to provide an exploded diagram and/or any instructions on disassembly.  However, this turned out to be a fairly straightforward affair as follows:

1. Tape some balsa (or similar material) on to the cab roof to protect the exhaust stack. (Don’t ask me why this is necessary)
2. Unscrew the four road wheels
3. Remove the four screws securing the chassis bottom (contains the wheel pick ups) and unplug the lead to the motor
4. Remove the two sets of wheels
5. Unscrew and remove the motor block
6. If necessary unscrew and remove the cab roof and the engine cover.

Step 2

Step 2  was to carefully drill out the existing 4 headlights in the die cast chassis and then file the opening to match the internal rectangular shape of the headlights.  The front two were reasonably easy but the back two required drilling through another section of chassis to make a pathway for the leads.  I also drilled a hole in the cab roof for a rotating beacon.

Step 3

Step 3 entailed soldering 38 gauge magnet wire to 0402 LEDs.  These are a good fit in the headlight holes and I installed them with plenty of Microscale Kristal Clear.  It’s important to remember that the chassis is die cast metal so you need to be really careful to insulate the LEDs. The Kristal Clear does a good job of this plus it makes good lenses.  An 0402 also sat neatly on top of the Cab Roof and it was only when I came to wiring up the decoder that I realised I didn’t have enough lighting functions – Doh.

Step 4

Step 4 was fitting the decoder.  The DZ123 is a really close fit in the chassis under the motor (see picture) but I did have to trim some of the excess heat shrink off the back of the decoder.  The orange and grey leads go direct to the motor (grey is the bottom motor lead) and the red and black leads were soldered to the original track pick up plug.  At this point I re-assembled everything to make sure the motor ran as it should.  Another word of caution – the screws retaining the road wheels just protrude into the chassis so make sure these don’t affect the decoder.

Step 5

Step 5 was to make a little circuit board for mounting the SMD resistors for the three lighting functions.  This sits on top of the decoder and leaves just enough remove to get the bottom of the chassis back on.

Step 6

Step 6 fire up Decoder Pro and get all the functions working properly – job done.

Well done

Dear Peter,

Nice effort, and good writeup! I have 2x analog Trackmobiles on hand (one active, one still NIB), and had been pondering the prospect of DCC install. I wonder if a TCS decoder would fit?

Happy Modelling,
Aim to Improve,
Prof Klyzlr

PS Imagine one of these on DCC,
with a consisted under-table TSU Cummins diesel decoder va headphones for the sound?
All kinds of switching fun....

Wow!

That is some serious tiny work!  Congratulations and thanks for sharing.  

@Prof

Hi Prof

Yep the sound would be fun. The DZ 123 is .36" x .55" x .13" or for us metric folks 9.1mm x 13.97mm x 3.02mm.  The TCS M4 is fractions of a mm larger in each dimension but might just squeeze in plus you would be able to do the extra light functions.

I now need to figure out how to get this critter to run through the frogs of a Peco 3 way switch.  However I have some other questions about 3 way switches which I will raise in a separate post.

Outstanding work!

Hi Peter;

Now I have a good reason to get a none DCC trackmoble and wire it up. It does not look like that hard a project to take on..

I will be visiting my local hobby store and picking one up. 

Thanks for the idea,

Wes Garcia

Sioux Falls, South Dakota

Sound

....someone actually has put a sound decoder in these with lights and put up some videos on youtube.

Will search it out and let you know. 

found video

All that Gorgeous Aliasing...

Dear GetSmart,

I'm loving the effort involved, but the digital aliasing evident suggests a rather lo-spec 8-bit decoder/source,
OR a severely impaired camera/mic/YT-upload workflow...

(No, we can't "just blame the speaker" in this instance,
the audible high-frequency distortion is clearly lo-res digital-audio aliasing,
and is easily reproduced/recreated in any audio editor...)

Happy Modelling,
Aim to Improve,
Prof Klyzlr

@ Wes

Hi Wes

I am glad I have inspired you to do one.  I just hope you have some experience with 0402 LEDs.  My first attempts were frustrating to say the least but after quite a bit of practice I am starting to get the hang of it.  Once you do it opens up all sorts of interesting possibilities.  I would strongly recommend the tutorials and equipment on Ngineering's web site http://www.ngineering.com/accessories.htm.  Not sure if they are an MRH advertiser but things like their Magnet wire and LED holding tool make life so much easier.  I would also strongly recommend their Low temperature solder and a temperature controlled soldering iron.

A further addition

Another frustration with these little critters is the lack of a working coupler at the front.  I have now successfully fitted a Kadee coupler to the front which has made the machine a lot more versatile in my yard.  If anyone wants to see some photos of that addition, sing out and I will post them up.

Neil Armstrong did walk on the moon

Neil Armstrong did walk on the moon, correct?

Do you think that video is faked.  The camera quality is crude along with the audio but it seems this  guy has sold about 20 of these units around the world with satisfied customers. 

He does have more than one video of these trackmahines with different roadnames with light and sound.

BTW its not my video.

Beware I could be a freemason.

Not faked, just audibly aliased

Dear GS, Trackmobile fans,

I'm not saying it's faked, I'm just saying the audio demonstrates a disturbingly familiar symtom of lo-res digital audio playback,
(high frequency aliasing distortion), which is commonly (and invalidly) blamed on the speaker :-(

That said, still an amazing effort in the install and wiring dept...

RE Front Coupler

Recipe
- obtain 1x #58 scale coupler
- cut the shank directly in front of the flared mounting section
(IE you are removing the flared section, leaving just a straight "shank stub" projecting from the rear of the coupler head)
- drill a 5/64" hole directly below the plastic cast "load sharing" coupler, making sure it's on the frame centreline and parallel to the rail-tops
- With a minor ammount of filing, the resulting shank should fit directly into said hole
- apply smallest dab of epoxy or ACC to the shank, make sure the coupler head is oriented correctly,
(needs to be perfectly vertical, and the right-way-up, don't laugh...) and insert in the hole
- set aside to dry, and you're done...

NB that due to the very short wheelbase, the lack of coupler swing is not a significant issue for most Trackmobile<> car combinations...

Happy Modelling,
Aim to Improve,
Prof Klyzlr

Amazing

I never knew that these tiny trackmobiles had Alco 251 turbo engines in them.  

Bernd

Trackmobile

Have any idea at all where you can get one of these baby's in N Scale.  is an awesome looking rig

N scale

Darn

Maybe one day.  Will cross my fingers.  Is as hard ta get these things in the smaller scales  as N Scale service walkways for my yard.  Thanks for your reply kind Sir, and will keep optimistic for sure 

@ James

Check on Shapeways ever so often.  You never know when someone might 3d print one for N scale.  Over a year ago I found a 3D printed N scale Boxcab, with a Kato drive, on eBay, but that was not printed via Shapeways.  The seller was in Germany.

To make it run you might have to have a powered boxcar to push it around or see if there is a flea drive small enough to fit such a compact vehicle.

Den

Switching Work, & Peco compatible?

I have a similar problem I have just run into, how to get some of my container cars out of the loading/unloading in my peninsula facility. My runaround track is very short (not sure if that's the corrected term), and a std length switcher might be just a bit too long. Immediately I thought of this Trackmobile.

How has yours worked out as a switch engine?...reliable, powerful enough, etc??

Did you work this problem out? I'm looking at having a Peco double-slip turnout in my exit tracks for container loading/unloading area. This might present problems like yours? How about keep alive?

(when I saw the lights on the 'image page reference' I thought this was going to take me to a discussion I saw recently about flashing light installation,...I guess that is in a different subject thread)

Just like the full size..

... it is not designed for hauling large cuts of cars.  Keep it to one or two and it works fine. 

In terms of difficult track work, you have to bear in mind that the wheelbase on these things is only 40mm (just over 1.5") so performance over complex turnouts is not going to be flawless.