N Gauge Model Railway - Episode 13 - Secondhand Buildings from eBay

As I aluded to in my last episode, I bought a joblot of secondhand N Gauge buildings from eBay for the bargain price of £19.

I decided to buy kits because whilst I would love to scratchbuild every model on my layout, to be honest, I do not have the patience or the skills.  The aim of the game here is to get something on the layout to fill in the gaping void in the middle and to add some lighting.

Each building will have its own blog where I will document the customisation process in more detail and explain all the trials and tribulations involved when working with 40 year old plastic kits.

These kits are namely:

KleiWe - 203 Stadthaus (Townhouse)

I didn't realise that these kits are so vintage having been produced between 1967 and 1971 before being bought by the Arnold brand.  In unbuilt boxed condition these are quite the collectors item so I feel a tiny bit sad that I am going to hack them up.  I found a little bit of information regarding this short lived range on The Birth of N Scale blog. 

This is a very European looking structure, but I quite like it.  The fancy stepped gable detail is very reminiscent of Dutch "trapgevels" architecture. This is clearly a more upmarket or municipal building. 

On the layout it currently sits directly opposite the Heljan Meat Packing Plant I built last episode and it would seem fitting if this were the offices of the local district council.  Perhaps the fortunes of both entities are somewhat intertwined. 

Heljan 672 - Furniture Factory 

I appear to be missing some of the parts to this model namely the base which includes a sort of loading dock.  No matter, as this is going to be my "Tex Mex" restaurant in the style of Chiquitos or Nandos.

KleiWe - 202 Mietshaus (Tenement House)

Another KleiWe kit, but this one is a lot less European in it's roof detail an looks much more utilitarian.  I'm thinking that this would be a perfect fit as a police station.  It sits on a dead end which will provide ample parking for the MFP liveried Falcon XBs that I intend to police Upper Carrom.

Kick her in the guts Barry!!

Auhagen 14475 Factory Building

This kit is still in production and readily available.  Sadly I only have the rectangular administrative building part, but it will serve admirably as the Carrom College Halls of Residence.

Bizarrely this building had an entire set of windows with white frames instead of black.  This will not do and so I have already ripped them out and will replace with carefully laser etched replacements.  

Unknown Modern Warehouse x2 

Despite some hours spent searching I could not identify the manufacturer or model of this kit.  However, given that the rest of these models appear to be of german origin I expect this to be a long discontinued Faller or Pola kit.  Please feel free to comment below if you know the origins.

For my layout it absolutely screams budget German supermarket so I am going to make it an Aldi.  I have a second kit so if I get bored then I can always swap it out for a Lidl.

Bonus cardboard model - Builder Plus BPN9 Signalbox

I was surprised to find that hidden inside one of the buildings was this very dilapidated cardboard signal box.  This will be perfect sitting on top of the tunnel mouth overseeing the small shunting area and the station platforms.  

I understand that no railway architect in their right mind would ever dream of building a signal box on top of a tunnel and there is nowhere for the leverframes to go and all that real world stuff.  But this is my layout and I want it to be visually interesting rather than an exercise in prototypical modelling.

This thing is too cute for school, especially as it has an interior.  I feel it is only right and proper to do a full restoration and update it with some 3D printed replacement parts and lights.

I had never heard of the Builder Plus range but it was apparently part of PECO and after a bit of googling I discovered that some of the range is preserved in the Robert Freidus Paper Model Collection

Ressurection and Plug & Play

It is my intention to make all of these buildings as plug and play as possible and as I mentioned before my layout sits on top of a carrom table so there can be no dangling wires underneath the baseboard (as is tradition).  This means I have to carve out channels in the MDF baseboard to snake the wires from my 5V USB powered chinesium distribution box through to each foundation and then terminate in a 2-pin female JST socket.  Each building will then plug in with the matching male connecter and feed power to a hidden distribution circuitboard to which all the lights will be wired with the appropriate resistors.

I am taking this bold step because it will take me some time to ressurect each building one at a time and that is a much easier task if it is done at the workbench rather than huddled over the layout.

To make this a robust solution, I designed a JST baseboard adapter which can be glued onto the MDF and provide a sturdy location to seat each female socket.

2-Pin JST Socket Baseboard Adapter - Thingiverse - thing:7026971

I printed a bunch of these in resin fished the wires through the hole and glued them to the baseboard.

I bend over the pins of the JST socket before soldering on the wires.  I have adopted consistent polarity for connecting the pins making it a trivial task to wire up the male JST plugs safe in the knowledge that they will always be the right way round.  

What I love about the ubiquitous and cheap as chips JST connectors is that if you get this wrong you can quickly depin the plugs and swap around the wires.

Anyway here's a shot of one of my buildings with the JST socket baseboard adapter installed.

This is a free download from all the usual places including Thingiverse, Cults 3D, Printables.  If you like it and find it useful please drop a comment and give it a like wherever you downloaded it from.

Obligatory Running Video

Enjoy...

N Gauge Model Railway - Episode 12 - A Heljan Meat Packing Planet and LED Circuits

Back in March I was busy buying secondhand buildings on eBay to fill out the center of the layout.  I also bought a few brand new (old stock) kits from Heljan and Gaugemaster (Kestrel) to satisfy my need to get this layout moving forward.

Heljan Meat Packing Plant -  N673

I don't know anything about Heljan other than Sam's Trains on YouTube regularly gives them hell about their OO locomotives.  The kit came in a slightly squashed box with a few sprues inside.

Initial assembly was relatively easy once you have worked out that the letters on the instructions relate to the the letters on the parts which must join together.  The basic structure went together very easily but the configuration of the highest roof is a bit odd and leaves an unsightly gap.  Furthermore, my intention was to light this top most area and it is essentially sealed off once you add the roof.

Painting with Jason Jensen

I'm a big fan of the work of YouTuber Jason Jensen, his densely packed urban layouts in OO and N Gauge are just a sight to behold.  However, I'm no ex comicbook artist with all those thousands of hours worth of drawing and inking to fall back on.  The beauty of Jason's channel is that he shows you how you can easily add character and weathering to a structure just with some paint and a bit of sponge.

The building was primed in black and given a white zenithal highlight.  This is a fancy way of saying I sprayed the building with white paint from above to highlight the bits which would be hit by the sun at it's zenith.

I then proceeded to sponge on a few different shades of brown to simulate the varied coulour of the brickwork.  There's no secret sauce to this recipe and you can pretty much use whatever paints you have at your disposal.  Just remember to dab on less and less as you go from dark to light. 

I did not bother to follow the spackle mortar step as I was really happy with how this turned out and I have no idea what spackle is 🤣.

All the woodwork, doors and trim came seperate on the sprue so this was painted before assembly with a quick zenithal prime and then a base coat of two of my least used D&D acrylics from a Nolzur's starter set by Gale Force Nine.  These were specifically Putrid Slime and Xanathar Blue.  Honestly these are crap paints and I do not recommend that you buy them, but they do produce a nice sea green colour when used together.

Palethorpes Signage

I have 3 Lima Siphon-G wagons in my fleet, one of which is branded with Palethorpes Sausages.  I naturally thought that this meat packing plant should be a Palethorpes factory serving the local community of Upper Carrom.  Grabbing some suitable images from the internet and resizing for printing using GIMP was a trivial exercise.

I followed Jason Jensen's weathered sign technique.  This involves sanding the back of your printed paper sign until it becomes almost transparent.  I cannot believe that I spent half an hour of my Saturday morning carefully sanding paper to make it even more paper thin.  We do what we must in the pursuit of happiness. 

This was then stippled onto the textured brick work with diluted white glue and I have to say I was impressed at how well this technique works.  You can see the ghosted image of the underlying brickwork on the lighter coloured backgrounds and it is quite convincing.  Now that I know what I am doing, I am going to be braver and go for even thinner more realistic signs in the future.

Lighting the model and adding a circuit board

My intention with the majority of the buildings on the layout is for them to be removable so that I can work on them off the layout.  This lends itself to the "plug and play" mentality where each building has a single connection to 5V power and is then distributed to each LED from a circuit board.

This model has a sum total of 6 lights.  Three are 5mm bright white LEDs for the building lights and then there are 3 bright white streetlights.  To be honest I have long since lost the packaging that the lights came in and it was all Chinese to me as it came from Aliexpress.

Following the excellent tutorial on How to Wire Multiple LEDs: Series vs Parallel by Rachel de Barros I built a small circuit board to accommodate all the lights.

The circuit diagram is as follows

This worked wonderfully for about 30 minutes of continuous use until one of the street lights failed, then another and then the third until this went pop but as I had encased it in photosensitive resin it smoldered for a while and stank!!.  Why did this happen?

Because I am a dumbass!!  

The eagle eyed of you will have spotted that I had wired the positive leg of the Street light LEDs in at points A, B and C and then soldered all the building lights in at D.  This completely by-passed all the resistors and sent each one 5V from supply. 

I initially blamed Chinese fake LEDs, but no wonder they failed, nothing can withstand that much power and survive.  

It is only by writing this blog that I spent the time to dissect the circuit and recording what I actually did and compared it to the circuit diagram (what I thought I'd done) that I discovered my catastrophic mistake.  This is called learning through failure boys and girls and is the best type of learning their is.

However, I do have photographic evidence that, however briefly, it did work.

Obligatory Running Video

This week's video is a bit on the short side but it does illustrate the 

 

Cheap Chinese Soldering Irons - Are they worth the money?

Embarking on the odd electronics project over the last few months has had me sucking at the teat of Aliexpress.  As my previous solder station (a Lidl Parkside special) was almost impossible to find tips for at a reasonable price. I dipped my toes into the water and bought a cheap chinese soldering iron.

80W Chinese Digital Soldering Iron - Under £10

At an almost ludicrous price I was not expecting much.  It came loosely packed with a set of tips a sponge and a pressed metal stand.  Sadly it was equipped with a two prong Euro style cord rather than the far superior UK 3 pin plug but I could not find any UK plug variants at similar prices.

The iron has a small digital display and two buttons marked + and - .  The instructions did not cover basic operation but after a bit of trial and error I worked out that:

• 1 short press of the + or - button allows you to set a target temperature 1 degree at a time
  
• 1 long press of  the + or - button allows you to change target temperature quickly
  
• 2 rapid presses of the + button switches between Centigrade and Farenheit temperature measurement.

Light as a Feather 

As with a lot of mains powered hot tools such as pyrograves, soldering irons and hot glue guns they are extremely light.  They are often lighter than the mains cable they are attached to and so are constantly making a bid to throw themselves off the table.  

The stand provided does an excellent job of preventing this from being a major problem.  However, there is nowhere to place the provided sponge. 

Easy to Overheat

As a relative newbie I found it was too easy to casually or accidentally change the temperature as I was soldering leading to oxidation building up on the tip and then a lengthy cleaning exercise.

What is the best temperature to solder at?

I found that 350 degrees C is the best temperature for soldering.  However, due to the design of these irons it is so easy to accidentally change the temperature that constant monitoring is essential.

Invest in a Brass Wire Cleaner

This is where I chose to supplement my meagre little collection of soldering accessories with a brass wire cleaning pot.

A Simple Solder Station - Thingiverse: Thing 6809777 

I designed a simple soldering station baseplate to organise the supplied stand and sponge and to accomodate a tin of brass cleaning wire.  Your stand and wire pot dimensions may differ so please feel free to remix this model.

Mega City Block Upgrade - Arduino Nano MAX7219 Display

A while ago I built a Mega City One Miniature Cary Case for my Judge Dredd miniatures and it was always my intention to have some sort of digital display which I could display random "in game" messages and to send instructions to the players such as ROLL FOR INITIATIVE.

The Components

Arduino Uno / Arduino Nano

I'd been itching to mess around with an Arduino microcontroller for years but never had the courage to just dive in.  However, there are so many people on ebay and Aliexpress selling ridiculously cheap arduino kits that there really is no barrier to entry. 

I plumped for an Arduino Uno Rev 3 Starter Kit which included a breadboard, jumpers and a whole pack of additional resistors and what nots.

The goal here is to make a small form factor self contained device so migrating from the large Uno dev board is essential.  I ordered a random Nano board from Aliexpress before realising that they come in 3 varieties with different board to PC connectors.  the cheap one I had picked came with an old style mini USB B connector and no lead.  Fortunately I had an lead from an old digital camera to use in the meantime, but I quickly ordered a bunch of nanos with USB C connectors for this and other projects I have in mind.  

MAX7219 8x32 Dot Matrix Display

The perfect lo-fi display for this project is a MAX7219 LED 8x32 dot matrix display.  It's small enough to work as a standalone unit and can take its power from the Arduino itself.  I bought one from AliExpress for only a couple of pounds. 

Wiring the MAX7219

I grabbed a bunch of dupont wires (these are the handy dandy push pin connectors which you get in your arduino kit.  I chopped one end off each wire and soldered them to the MAX7219 pins:

• VCC - Purple - 5v
• GND - White - GND
• DIN - Black - Digital Pin 11
• CS - Blue - Digital Pin 10
• CLK - Grey - Digital Pin 13
  

Wiring the Button

The button is wired into:

• VCC - Red - 5v
• OUT - Orange - Digital Pin 7
• GND - Yellow - GND
  

Entering the The Matrix Code

A bit of googling discovered the perfect code in the form of MAX7219 Message Selector on the Arduino Forums by user groundFungus.  Some tweaking later and I had a bunch of messages which I could toggle through with the addition of a button push on PIN7

// Program to demonstrate the MD_Parola library
// button select canned messages
// MD_MAX72XX library can be found at https://github.com/MajicDesigns/MD_MAX72XX
// by groundFungus AKA c. goulding

#include 
#include 
#include 

const byte  buttonPin = 7;    // the pin that the pushbutton is attached to

// Define the number of devices we have in the chain and the hardware interface
// NOTE: These pin numbers will probably not work with your hardware and may
// need to be adapted
#define HARDWARE_TYPE MD_MAX72XX::FC16_HW
#define MAX_DEVICES 4

// Scrolling parameters
#define SPACE_IN      A5
#define DIRECTION_SET 8 // change the effect
#define INVERT_SET    9 // change the invert

#define CLK_PIN   13
#define DATA_PIN  11
#define CS_PIN    10

MD_Parola P = MD_Parola(HARDWARE_TYPE, CS_PIN, MAX_DEVICES);

// individual messages in strings
const char msg_1[] = "<< WEATHER ALERT>> RAIN IN 10 MIN <> SECTOR 237 RIOT IN PROGRESS <> HOTTIE DAWGS ARE GOOD TO EAT <> BE GOOD CITIZENS LITTERING IS A CRIME>>  ";
const char msg_2[] = "<> ROLL FOR INITIATIVE>>";
const char msg_3[] = "<> GET UGLY GET OTTO SUMPS OIL OF UGLY TODAY!! >>";
const char msg_4[] = "<> HEAVY TRAFFIC ON THE BIG MEG CHOOSE ALTERNATE ROUTES >>";
const char msg_5[] = "<> THIS AREA IS IN LOCKDOWN >>";
const char msg_6[] = "<> CLEAN UP CREWS IN TRANSIT >>";

// an array of pointers to the strings
char *messages[] = {msg_1, msg_2, msg_3, msg_4, msg_5, msg_6};
byte messageNum = sizeof(messages) / sizeof(messages[0]);

int buttonPushCounter = 0;   // counter for the number of button presses
int buttonState = 0;         // current state of the button
int lastButtonState = 0;     // previous state of the button

void setup(void)
{
   Serial.begin(115200);
   Serial.println("\nParola pick a message program\n");
   P.begin();
   pinMode(buttonPin, INPUT_PULLUP);
}

void loop(void)
{
   if (P.displayAnimate())  // time to show next frame?
   {
      P.displayText(messages[buttonPushCounter], PA_CENTER, 50, 3000, PA_SCROLL_LEFT, PA_SCROLL_UP);
   }
   checkButton();
}

void checkButton()
{

   static unsigned long timer = 0;
   unsigned long interval = 25;
   if (millis() - timer >= interval)
   {
      timer = millis();
      buttonState = digitalRead(buttonPin);
      // compare the buttonState to its previous state
      if (buttonState != lastButtonState)
      {
         if (buttonState == LOW)
         {
            // if the current state is LOW then the button
            // went from off to on:
            buttonPushCounter++;  // add one to counter
            // if counter over number of messages, reset the counter to message 0
            if (buttonPushCounter >= messageNum)
            {
               buttonPushCounter = 0;
            }
            //Serial.println(buttonPushCounter);
         }
      }
      lastButtonState = buttonState;
   }
}

Debugging the Code

Unfortunately this particular code only reads the button state at the end of each scroll.  This is where an interrupt is going to be necessary.  The arduino Uno and Nano boards that I have access to are only enabled for interrupts on digital pin 2s and 3 and will necessitate a bit of a rethink in the code 

MAX7219 Case - Thingiverse: Thing 6809712

No one wants to live in a run down cyberpunk world with exposed wires everywhere, so I needed a case for the display with enough depth to house the nano and the button which would switch modes.

I found a simple MAX7219 8x32 case on Thingiverse which I could easily embed magnets into to affix to the top or side of my Mega City Block Storage Case.  Sadly this did not fit my particular MAX7219 board as the pins came out sideways.  

This was easily fixed with a bit of modelling in Sketchup and if you need a case and have side exit pins feel free to download this from Thingiverse using the link above.

Mega City Block Upgrade - The Okey Dokey Chef

Once you start pimping out your Mega City One Block Storage Case it's hard to know when to stop...

The Okey Dokey Chef Animated Sign

I wanted my sign to be an advertising hoarding and one of the most famous signs in Mega City One is the Okey Dokey Chef as featured in the Supersurf 7 race story Midnight Surfer (progs 424-429).  I was also inspired by the famous Vegas Vic neon sign whose arm waving welcomed gamblers from all around the globe since 1951.

He wold make an excellent starting point to learn about how to control low voltage RC servos with Arduino.

The Chef

I found a nice piece of clipart online which had the vibe I was going for and imported this into GIMP for editing.  

I cut out the "Chef's Kiss" hand using the lasso tool and moved this over into  a seperate file.  This is going to be the sweeping hand which we will animate later using a servo.

I added a speech bubble with some appropriate text coming out of the side of the chef's head. 

Preparing for Tinkercad

I have learned that Tinkercad is a pretty simplistic modelling tool and it does not particular like creating complex curved or polygonal shapes.  The easiest way to solve this conundrum is to simply create a solid black mask version of your line drawn artwork.  This can be used as a background and because both shapes are exactly the same image size, they will register perfectly together when you import them into Tinkercad.

When I was happy with both files, I and exported them (and their solid black mask counterparts) as a PNG then converted into an SVG using convertio.com.  Each line drawn SVG is imported into Tinkercad for extrusion into a 3D object using the same technique I used to create my badges and Index Card RPG Card Back Stamps. I use an extrusion height of 30mm.

The black mask variant is then imported and the combined shapes exported as a single STL.  This gives me an STL file for the chef and a file for the arm which can be printed on the Anycubic Photon M5.

The Electronics

The core of this project is an Arduino nano.  These little boards are stupidly cheap and really easy to start your coding adventure.  Seriously, if an idiot like me can do it then anyone can.

The bit doing all of the moving is a 9g 5v 180 degree hobby servo which I bought in a twinpack from Ali Express for £1.79.

This was superglued across the gap between the Speech bubble and the chef's arm.

The Wiring and Code

I used the excellent How to Control Servo Motors tutorial on the makerguides website.  The servo has 3 wires Red (5v Power) goes to the 5v pin,  Brown (Ground) goes to the GND pin and the Yellow (Signal) goes to Pin 9.

The code example given is perfect for my purposes, but I did need to customise the start and end positions for the hand as it does not need to run the full 180 that the servo is capable of.  I also added a 500 millisecond delay at the end of each travel.

#include 

Servo myServo;  // Create a Servo object

void setup() {
  myServo.attach(9);  // Attach the servo to pin D9
}

void loop() {
  // Move from 30 to 135 degrees
  for (int pos = 30; pos <= 135; pos += 1) {
    myServo.write(pos);  // Tell servo to go to position in variable 'pos'
    delay(45);           // Wait 15 milliseconds for the servo to reach the position
  }
  delay (500);
  // Move from 135 to 30 degrees
  for (int pos = 135; pos >= 30; pos -= 1) {
    myServo.write(pos);  // Tell servo to go to position in variable 'pos'
    delay(45);           // Wait 15 milliseconds for the servo to reach the position
  }
   delay (500);
}

Troubleshooting

In my naievete I thought that the Arduino nano would be able to power this whole project.  However, the little servo apparently draws too much power to run continuously causing the nano to reset itself and creates some erattic animation.

I tried to mitigate this by adding increasing the dealy to 45 thereby slowing down the move, but sadly this was not enough.  It would have been nice to know all this from the start as an alternative board such as an ESP32.  

Anyway that is another story.  In the meantime check out the final result

Download the Files

I have also uploaded the Okey Dokey Sign STL files to Thingiverse if you should want to make your own version of this iconic comic book sign.

Let me know if you found this useful or if you have made your own animated signs for your own games

1:30 Scale Nax Fishing Vessel - NTKJ MODEL - Part Two

In Part One we got the basic hull together 

Sanding and More Sanding

As I mentioned the hull is made of straight ply planks and there are a lot of gaps and seams which require filling with wood filler.  I bought a tub of 151 wood filler which I thought was going to do the trick and I was dissapointed that it was more like wall filler than anything else.  Still I persevered and ended up slapping on a ton of the stuff.  

In hindsight I would do this totally differently.  The filler oozed between the planks and ended up inside the boat hull trapped between the frames which then dried and fell off.  I have in effect created a boat shaped maraca.  

This necessitated opening up the deck under the wheelhouse in order to release the now rock hard filler.  This might sound like major surgery, but as the deck is so thin it was easily acomplished with a sharp craft knife and a steady hand.  I made sure to keep the offcut as I have plans for that later.

The way to tackle this is to use the old superglue and baking soda trick to fill up the gaps.  This of course only works if you are painting the hull.  If you are going for the natural wood finish then you are going to have to get better at laying the planks. 

Painting

Painting the boat in sections is unavoidable at this stage.  I carefully masked off the deck and gave the now smooth (ish) hull a spray coat of white primer followed by a couple of coats of white gloss.

The airbrush then came in handy for painting the decks with a Vallejo Burnt Umber wash.

The remaining wooden pieces for the wheelhouse, deck covers and the gunwhales were then extracted from their boards and sprayed with the same Vallejo Burnt Umber wash. 

Adding Some Colour

I imagined the boat a sort of tri-tone with a red top stripe white hull and black or red hull bottom.  In the end I just gave it a stripe of red on the sheerstrake plank and continuing around the transom.  Masking this off was a tricky exercise as I only had some really nasty cheap painters masking tape.  I will have to come back and do some tidying up by hand later.

Trial fitting the wheel house accents and deck hatches really makes the boat come alive.

You might beable to see in the photo above that I managed to glaze all the windows with some clear acetate from some recycled packaging.  I glued this in using my now favourite hobby glue UV Resin which I picked up in my Wish Hobby Products 2024 experiment.  This stuff is amazing.

Adding the Lights

Last year I picked up some micro LED lights for another project (which I have yet to start).  These are incredibly tiny and come pre-soldered onto super thin magnet wire.  I quickly soldered a couple of these together with a CR2032 coin cell battery holder and a latching push button and stuffed it into the hole.

I will probably tidy this up with a piece of perfboard at a later date as the circuit is tiddly. I am also undecided if I will add any navigation lights.  For the uninitiated this mean a RED LED for the left (Port) side of the boat and a GREEN LED for the right (Starboard) side.  I have some 3mm LEDs from another side project but these might be too large, we will have to see.  Adding them to the circuit should be no problem and might even add some much needed resistance to bring down the brightness.  

The LEDs were then routed up through the floor of the front wheelhouse and up one corner.  One LED illuminates the interior and is bonded to the roof with the UV Resin and the other goes outside in front of the cabin as an exterior deck light.  I will need to find an appropriately nautical shroud for this exterior light as they are suprisingly bright for their size.

Oh did I forget to mention that I added a salty seadog to steer this fine boat across the treacherous seas? 

He is one of the many 3D Printed accessories I covered in part one of this mini series.  A fine free model although he is now sealed in his cabin for all eternity as I have glued on the roof and floor.  

In the next, and final part of this mini series we will add all the accessories masts and rigging.