Sunday, January 28, 2018

A warehouse with no name.

The 8 ft Battle Mountain section has now been bolted into it's place in the layout and the first of it's four industries is completed.

This first industry is just a shallow relief warehouse building with 4 track doors spaced for 50ft box cars.

I don't have a name for the business that occupies this building but here is the story.   There are a variety of clay like minerals with funny names are mined in this part of Nevada that are used in many products and processes.  The company that is located in this building receives some of these minerals by truck to make their products which are mostly shipped by rail.

This company makes one of the leading premium brands of cat litter which is packaged in 25 or 50 pound bags stacked on pallets and shipped in box cars to several distribution points around North America.    They also ship some of their product by truck but that is not modeled here.  This would be a good sized facility but only the railroad part of the warehouse building is represented on the layout.

Wednesday, January 17, 2018

Reuniting a Walthers Interstate Fuel & Oil kit

One of the industries that will be in Battle Mountain will be a bulk fuel distributor receiving product by rail and shipping by truck.   Turned out that I really didn't have to buy anything to build this as I had parts from a Walthers Interstate Oil kit that I had purchased about 25 years ago and used parts of it on several different scenes on my modules and old layouts.

The building had been used in a junk yard scene, the loading platform in a refinery, and the pump house in an oil field.  Some finished tanks used in a locomotive facility got sold on ebay but I still had enough tank sections left over to assemble two more tall storage tanks.

So now almost all the remaining parts from the original kit will be together again on this layout.  Goes to show that if you carefully pack items removed from a layout they can be kept safe and used again.

What I like to do with structures or detailed scenes is to create a little depression in the surrounding scenery by gluing styrene strip around the structure or in the case of a scene I create a little base.  The scenery is then built up around the outside and the structure or base can be placed inside the depression.

In the case of the group of smaller structures in the middle of the fuel distributor I made a base from a scrap of fiberglass reinforced plastic with the smooth side up.  This scene can be now completed on the work bench and installed on the layout later.

The original loading dock on the building was damaged so I built a new loading dock that is actually attached to the scenery base which in this case is a .020 thick styrene sheet with .040 x .040 styrene strip perimeter.

This next photo shows the building placed in it's spot.  The fit is snug enough so not to be easily knocked loose with normal layout usage but can be easily removed for access or maintenance.  On modules I do something similar as shown in these examples but with screws added to hold the building or base onto the module.

More on this fuel distributor in future posts.

Thursday, January 11, 2018

My first Arduino project - a grade crossing

I have always wanted to create an automated grade crossing. Several years ago I had purchased a grade crossing bell sound module and a pair of NJ International crossing signals with LED signals.  I have experimented with these items a few times but never got around to actually incorporating them into a layout.

As mentioned in the last post for the past few years I have also been experimenting with Arduino micro-controllers.  It was time to bring everything together.  The road that connects a few industries in Battle Mountain to the rest of the world seemed like a good place to finally create a nice crossing scene.

It was a bit of work but I have the results I was looking for, an automatic grade crossing signal with flashing lights and bell sound.  Work remains to be done to finish the scene but this photo shows it working.

It took all this hardware under the layout to make this grade crossing happen.  Probably not the most efficient setup but it works.

Infrared sensor pairs are hidden in the scenery on either side of the grade crossing.  In this photo looking up from a low angle one of the receivers can be seen inside a cave in one of the rock outcroppings.  At a normal viewing angle this is hardly noticeable.

Transmitters are embedded into the scenery on the ground on the other side of the track and because they face away from the viewer they can't be seen at all.

And now for the tricky bits

Here is the complete schematic drawing of this project.    After almost 1 year with a new computer and learning new versions of software,  I think I am finally getting up to speed with the latest version of Microsoft Visio.

The code and some other notes:

This program is only using part of what the Arduino Nano can do and only using a small part of space available for program storage.

No gates on this crossing but they could be could be added if desired using left over outputs.  I have seen on the Internet where the analog outputs can be used to drive a servo but I have not tried this yet myself.

Arduino outputs are rated for 40ma.  There are a total of 8 LED's on the signals wired in pairs.  I measured the current flow on each pair of LED's at 6ma so two outputs could have done them all but since I had extra outputs I elected to use 4 outputs with each output running 1 pair of LED's.

Sound module runs continuously with connection to the speaker controlled by the relay.  One sound module could be used for multiple crossings with each crossing having it's own Arduino controlled relay module.  The sound module will drive a small 8 ohm speaker.

Approximate costs and sources:

  $5.00 - Relay module, ebay
  $6.00 - Arduino Nano, ebay
  $4.00 - Arduino Nano terminal adapter board, ebay
$89.95 - Azatrax MRD8 detector set,  Azatrax
$39.00 - Sound effects module, ITT Products
$35.00 - Crossing signals, NJ International

I had originally acquired the 8 channel Azatrax unit to work with staging yard automation and plan to replace it in this application with a pair of single channel units at $20.00 each and move the MRD8 to it's original purpose.  Azatrax also offers a unit specifically for grade crossings which might not require the use of an Arduino at all.

Now that the ice has been broken for me with the Arduino I hope to try out some other projects in the near future.

Sunday, January 7, 2018

Experimenting with Arduino micro-controllers

When I was still working one of the systems I was responsible for used an Allen-Bradley Programmable Logic Controller or PLC.  The PLC itself was so reliable it never required any repair and I just had to make minor programming and wiring changes depending on my employer's needs.  I used to think something like this would be great for doing things on a model railroad but of course these PLC systems are for commercial applications and are not cheap.  So what I was really thinking of was something similar but smaller and at a consumer price.

Shortly after retiring 5 years ago I discovered the Arduino line of micro-controllers and purchased a Uno board at Radio Shack to play around with.  I taught myself to write some code for it and set up several simulated model railroad applications with LED's on a proto-board but found the mounting and connections to be awkward for practical applications.
More recently I discovered the Arduino Nano on ebay which does about the same job as the Uno but is physically a bit smaller.

What makes it work for me is that for a very reasonable price I can get a terminal board kit that  the Nano plugs into and that has mounting holes.

The programming is done by using an editor program downloaded from the Arduino web site.  The programs are checked and compiled by the editor and loaded onto the Arduino by USB connection to your computer.

The outputs of the Arduino are limited to 40ma which is fine for most LED's not for bigger loads such as a relay.  These small relay modules are powered separately from the Arduino and the input uses an opto-isolator device so the output of the Arduino is protected.  These come in single or multiple relay configurations and are also reasonably priced on ebay.

So with these building blocks I am ready to start some practical projects on the Palisade Canyon layout or on my Ntrak or AsiaNrail modules.  Some of the ideas I have include:

  • Grade crossing flashing light and bell
  • Staging yard controls
  • Point to point operation with stops and turnouts
  • Model buildings lights on and off
  • Signal controls
  • RFID reading and train routing

Thursday, January 4, 2018

Experimenting with Infrared detection circuits

Looking at some different options to trigger the grade crossing signals that I am planning for the Battle Mountain section and thought I would try an off the shelf product that uses pulsed Infrared or IR light.  IR light would have an advantage over normal photocells because it is less likely to be effected by room lighting and would work even in the dark.  I still have my "test layout" with Kato Unitrack which will be used to check things out before actually installing anything on the main layout.

For my experimenting I am using the Azatrax MR8D board.  Power for it can be from 8 to 16 volts AC or DC.  It can support up to 8 transmitter / receiver pairs and provide a solid state contact closure output for each of the 8 channels.  Each channel has an LED indicator which lights when something breaks the invisible IR beam between transmitter and receiver.
The set came with pairs of transmitters and receivers with leads attached and styrene tube protecting the connection.  The devices themselves look like 3mm LED's.

The Azatrax instructions recommended setting the devices at an angle across the track so the beam would not pass through the space between cars.  I used flat head screws and cut the styrene tubes into short lengths to hold the devices.  A 1/8 inch brass rod through both tubes holds the alignment until the adhesive sets.
I installed one set at a 3/4 inch height and another set at 1/2 inch height.  I then made up a test train with one each of several types of freight cars.

The 3/4 inch height worked OK except for empty flat or well cars.  As the instructions had suggested, there was no problem at all with the spaces between cars using the angled arrangement.
The pair set at a 1/2 inch height worked well for the 50 ft flat car that failed on the 3/4 inch height but was too low for the tank car.

Thinking about how the lateral angle was used to prevent the signal from passing between the cars, I thought that using vertical angle as well could help

So I lowered the transmitter screw on the pair that I had set at 3/4 inch to 1/4 inch.

This worked the best with very few instances of the signal getting around or through any of the cars in the test train.
Where my grade crossing is the track has low hills on one side with some exposed rock.  My plan is to embed the transmitter in the foreground scenery at ground level and the receiver in the hillside scenery at a higher level.

This photo with the IR beam path drawn in shows how the sensors could be installed on the  approaches to the grade crossing.

The Azatrax IR detection circuit seems to work very well and come in several configurations.  To learn about what is available check their website.