Wiring Updates on Nooksack TOMA project

Wiring diagram for Nooksack

Spending some time with the Nooksack modules, particularly dropping new feeders for the track, I have been thinking about my approach to wiring for the railroad in general. First of all, I really appreciate how the TOMA approach allows me to wire without crawling around under the railroad. Beyond that, electrical work such as wiring a model railroad is not an aspect of the hobby with which I came with a lot of experience. Continued skill building is a goal for me. So, I will discuss three phases (electrical pun!) of wiring updates and skill building in this post. I continue to deal with attempting to improve my soldering skills with notoriously shaky hands. I find I am revisiting the electrical standards that I initially established for the Meadville attic model railroad.  The most recent consideration is proactively thinking about the NMRA AP and how it can be a guide to improvement in range of skills. 

Soldering with Shaky Hands

I wrote about improving my skills for bulletproof track and electrical work on my initial practice plank in an earlier post. Complicating my desire to improve my soldering and wiring skills, my always shaky hands are getting worse as I age. In the photo seen here, I displayed the tools that I used in soldering feeders to several sections of revised track. I find that the more that I can stabilize the items that I am soldering the easier it is to get a quick and clean connection. I added locking tweezers and adjustable clamps to the collection to do just that. Pre-tinning the items to be soldered, making sure that they are "clean" (hence the addition of the scratch brush to polish the rail) before tinning, and using thinner solder all help as well. Clamping down my badly balanced soldering iron stand and using higher quality wire strippers make the process move efficiently and allow me to approach the task calmly and more confidently. Another subtle change to my approach is to attempt to set everything up so that I can solidly rest my forearms on a surface to pivot my hands holding the iron and solder into position. Soldering is still not my forte, but I am improving. 

Electrical Standards for the DCC Bus Revisited

Early on with the Meadville attic railroad, I set up some wiring standards as seen in this post from 2015. I have not changed them much, but I want to restate them as I begin the newest version of the 4th Subdivision.

1. DCC bus will be #14 gauge Red and Black wire.
2. Track polarity will be Black "out" or towards the aisle.
3. Track feeders will be #22 Red and Black with new applications soldered under the rail. 
4. Feeder connections will be suitcase connectors (3M "Scotchloc" IDC 905).
5. Bus connections between modules will be Eurostyle terminal strips
6. As I establish power districts, some standards may vary. Longer DCC bus wires may be #12 twisted red and black. Screw type barrier strip terminal blocks with soldered spade lugs may be utilized. 

NMRA Achievement Program: Model Railroad Engineer--Electrical

While I am not positive I will actually attempt the AP Electrical, it provides guidelines and structure for improving skills and doing solid work. In addition to proactively documenting in case I may choose to attempt it, having good records in case of the need for troubleshooting in the future is solid practice. In addition to using this blog, I may create a binder really focused on the AP electrical guidelines. Without going too far into the weeds with the AP here, two areas that Nooksack meets are Section D: Propulsion circuitry diagram of section A and Section B. 1. Turnout. The diagram shown at the beginning of this post is a first step towards diagraming the the "Propulsion Circuitry" of the entire railroad. 

Section B of the requirements includes wiring and demonstrating three of a number of items including turnouts. The Nooksack modules have seven Peco Elecctrofrog turnouts. In the photo of one upside down seen here, the steps I took to prep the turnouts to have powered frogs can be identified. I clipped the two wire jumpers and used insulated rail joiners to insure that the powered frog was properly gapped. 

At the same time, I soldered jumpers between the closure rails and stock rails. I also soldered a green feeder to the underside of the now isolated frog area, assuming that I remember to use insulated rail joiners at the point rails when installing the turnout. 

In the schematic seen here, one can follow how the green frog feeder wire is routed to the SPDT switch in the Tortoise by Circuitron switch machine used in the Nooksack modules. When the switch machine is thrown, the internal SPDT changes the polarity of the frog. One aspect of wiring the Peco turnouts in this manner is that the wire spring in the actual switch must be removed. Because the spring changes the speed at which the turnout is thrown by the motor versus the speed of the SPDT switch changing the polarity of the frog, a short is likely to happen with the wire spring left in place. 

This schematic drawing is also needed as a supplement to the "Propulsion Circuitry" diagram seen earlier. In that diagram, the gaps and switches needed for the powered frogs are represented by the shorthand green rectangles which in turn are shown in more detail in this schematic. 

Now, instead of explaining, writing, and drawing, it is time to talk my wife into helping me spin the modules one more time and connect the new feeders to the bus wires and call the propulsion wiring on Nooksack finalized.