Monday, 28 October 2013

Electrical Bus

While the writer favors soldered connections it can be quite difficult when building a DCC power bus because of the need to expose the copper wire. This has lead to re-examining 'Suitcase Connectors' or Insulation Displacement Connectors (IDC's) which allow connection of track feeder to main bus (power supply) wires without having to strip or solder.  

To connect these connectors simply place the crimp over the wires and close the cutter with a pair of pliers. The metal tab pierces the insulation and connects the wires together ensuring a reliable mechanical connection of both wires.

Suitcase Connectors (IDC #567 Brown) for bus sizes #10-12 (max insulation OD .190 inch) and feeder sizes #14-18 (max. insulation OD of 0.145''). Package of 25. These are available from Micro Mart as there is no distribution in Australia.

Track power is supplied from the main bus that rings the completed layout with a NCE EB1 circuit breaker located in the modules electrical panel providing power for the track-work. The panel is located in drawers fitted in each module as outlined in the Modules Article.

The modules power bus is constructed with multi core 1.0 mm square bus and 0.5 mm square for track feeders. 

         Colour code for modules:
                                                        Red / Black  - Track Bus & Feeders
                                                        Blue - Common feeder for point frogs.

Track Connections
Each length of rail has a brass tab 45 mm x 2.5 soldered to the underside of the web. After the rail is spiked into position a tab fitted through a hole drill in the road base, soldered to the rail and the feeder soldered to the exposed tab at the underside of the road base.

The tabs are manufactured from scrap brass etches. Tin both ends then bend one end at 4 mm at 90 degrees - this creates a connection with a small profile and is very strong. It is recommended that a paste flux such as  Laco Regular Soldering Flux be used.

Track connection

It is CRITICIAL that before commencing assembly that it is confirmed the crimp makes contact with the copper wire of the bus and feeder. 

Even though the wire used meet specification there was a no connection on one of the first crimps. After investigation it was concluded that it was bad crimp but it dose open the possibility of poor connections being created during the crimping process. To be sure each cutter was removed and the larger cutter was given a few light taps to close it just a little. The wire was purchased from the local electronics shop and is a Chinese wire so for the rest of the project wire from a reputable supplier will be sourced. 

The first few crimps should be inspected carefully to confirm that the cutter and wire are operating correctly by exposing the edge of the copper on the wire. An alternative is to connect each feeder to the track as the last operation and buzz it before soldering to the tab. Overall this process offers a excellent way to speed up bus connection on any layout but materials should be checked for correct performance before commencing large scale assembly.

Bus Construction
Fixed end with cup hooks
The module bus is constructed from two lengths of 1.0 mm square insulated wire cut to fit between the former's. Fit a 6 mm ring crimp at both ends and do not strip wire insulation to insulate the wire from the rings. 

One end is fitted to a cup hook and the other has a tension spring is fitted between the hook and the ring crimp. The overall length of the wire is set to apply tension to the assembly and keeps the bus under tension making installing pillow blocks easier while keeping the bus tidy.

Cable Fixing Feeders

Friday, 25 October 2013

Spicers Creek Module A

Control Logic

Control Logic Deck Girder Bridges
The 3 span Deck Girder Bridge are equipped with separate NCE BOD's to allow each span's speaker to coordinate with the presence of rolling stock on that span allowing the sound to follow a train across the three spans. Sound is supplied by a pair ModelFXs Sound Byte sound player's fitted with a bridge rumble file. The sound player's are set to continuous play with one leg of each speaker wired through a NCE Dual Relay [dr] normally open contact. The NCE BOD [bod] detects the presence of a piece of rolling stock then sends an input to the NCE Mini Panel which triggers a output of the NCE Switch 8 operating the NCE Dual Relay coil which connects the speaker simulating the rumble created by the rolling stock running over that span. 

The length of the detector rail for the BOD's on the 1st and 3rd spans starts about 35 mm from the start of the span allowing the rolling stock to on the span before starting the sound. The middle span is a full length detector.

Control Logic Bridge Fans
The detectors on the opposite track triggers the fan controlled by a D13SR decoder operating fan's to move the mist collected in the creek bed by ultra sonic mist generators. The equipment control logic is the same as sound coordination for the bridge. 

The fans are controlled by the flickering firebox option applied to one of the four function outputs of the D13SR to create a fluky air movement. Each output will run through a voltage dropping circuit as the fans are 5V DC and the intend is to operate them at 3 volts and its hoped that this will move the mist around not blow it away. The first fan is begin prepared to be installed and is seen in the far right span. All the wire are to connect to the speakers, fans and track detectors.

Three span bridge before installation

The black wires are soldered to the underside of the rail and the rail will be isolated in five places for detectors

The large bundle of cables that have been cable tied in the foreground are to connect the bridge devices to their respective electronics located in the electronics drawer.  All the other bundles are for other specialized sounds to be incorporated. The red and black wires are feeder connecting to the track bus located at the rear of the layout.

Control Logic Flange Ring 
Flange ring [squeal] is controlled in the same manner as the the bridge sound and is located at two points on the curve before the three deck bridges leading to Goomla.

Control Logic Signal
The distance signal is controlled using a TAM Valley Dual 3 Way II decoder and servo. The decoder allows the operation of the Semophore in the two positions required with important feature its ability to simulate blade bounce. 

Sound will be created and coordinated with the operation of the signal to pull the signal chain using a light tension spring at a later date.

All the electronic hardware is fitted into the module drawer to allow repairs and diagnostics to be undertaken from one central point

Control uses a large amounts of wire as each circuit generally requires 2 cores. The use of 4 core alarm cable is the most practical means to supply the necessary cores and organization. This module has had 100 meters of cable laid in in preparation to connect the systems outlined and for other single point effects such as windmill, smoke and environmental sounds to help create the dynamic sound as discussed on a previous article sound control

Personal Comment
Will this all work?  

We are getting closer to finding out and there its a fine line between success and ridicule.

This is all a big unknown but as outlined at the start of this blog the writer believes there has never been a better time to try to create a "Theater for the Mind". Not my words but a perfect description for what is being attempted - time is required for judgement.

Wednesday, 23 October 2013

Gang Shed

Courtesy Bob Merchant / Ray Pilgrim 2013

As installed Spicers Creek

Gang Shed Fittings

Courtesy Bob Merchant / Ray Pilgrim 2013

Fettlers Cottage

Courtesy Bob Merchant / Ray Pilgrim 2013

Crossing Sign

Courtesy Bob Merchant / Ray Pilgrim 2013

Sketch 3 applies to Spicers Creek

Tuesday, 22 October 2013

Rabbit Trap Gangway

Courtesy Bob Merchant / Ray Pilgrim 2013

For more information go to Rabbit Traps Article

Monday, 21 October 2013

Distance Signal

Courtesy Ray Pilgrim 2013

Friday, 18 October 2013

Mile Posts

Courtesy Bob Merchant / Ray Pilgrim 2013

Road Crossing

Courtesy Bob Merchant / Ray Pilgrim 2013

Wednesday, 16 October 2013

Fence Details

Courtesy Bob Merchant / Ray Pilgrim 2013


Courtesy Bob Merchant / Ray Pilgrim 2013

Power Poles

The NSWGR recycled old rail for fences and power poles along the full length of its right of way. Ray Pilgram provided a series of photographs showing a series of line side power poles in various locations and while all are of a similar construction but there are too many variants to cover in this article.

Pole Construction


3D Solid Model Rendered Image 

The image for the cross arms was extracted from a Ray Pilgrim photograph taken at Werris Creek and clearly shows the arm construction allowing the 3D model to be created and the parts sent out for rapid prototyping. The model is about 25% oversize to allow the detail to be reproduced and to allow urethane casting. A separate photo of the Silver City Comet taken in the 80's out west provided a template for the poles.  

Technical Notes
Ray Pilgram on his Bylong Blog has posted some PDFs on the technical detail related to the installation of telephone poles on NSW Railways plus some additional notes of interest

The main document "Line Route Maintenance & Construction" has all the relevant details for those seeking to construct the rail based poles. There are another series of manuals for wooden construction on the same site for those seeking an alternative to rail. 

Cheat Notes:
The relevant points for modelling are listed below

Minimum rail length 30 feet [9 meters]

Spacing 165 feet [50 meters]

Standard cross arms are either 6 pin or 8 pin

The base of the rail faces the running track

The cross arm faces the Sydney side of the line except where wire stays are required and it can be varied for this

Cross arms for 6 pin are 3'' x 3'' x 5,-3'' [75 x 75 x 1600] - Timber tallow wood.

Cross arms for 8 pin are 3'' x 3'' x 8,-3'' [75 x 75 x 2500] - Timber tallow wood.

For complete detail link to Ray Blog and review the manual linked above.

Model Construction
Code 100 rail was used for posts cut 280 mm long [40 scale feet] with a etched brass V and urethane cross-arm with Peco pins rejected for spiking used to pin the V to the arm and rail. The spacer between the base of the V and the rail face is a length of 1/16'' diameter Styrene is drilled 0.020'' [0.5] and a Peco Track pin pushed through. 

All the rails and etches were sprayed using Tamyia Red-Brown with the the cross arm painted in Tamyia Sky Grey and finally the insulators with Hombrol Gloss White Enamel. This should be done before assembly. A alternative is gray for the V to represent galvanized finish - White Knight SLS primer is perfect and need no additional painting. 

The wire will be simulated using Berkshire Junction EZ Line heavy green between the poles. The green was selected as it provides a superior effect to other colors with the light catching the line in a most realistic manner when installed. The main feature of this line is its elastic construction preventing small strikes breaking the line with the disadvantage begin a lack of catenary sag but in service this has proven to be a practical sacrifice. An alternative is to use 0.010 [0.25 mm] CMA phosphor bronze wire that can be purchased on special order from the Model RR Craftsman.

The poles on Spicers Creek are set at 27 - 30 feet above track and at  120 - 150 mm from the edge of the running rail. The centres are set at 700 mm [100 scale feet] to give a sense of distance while reducing the load on the poles. On curves the poles have to be closer due to restriction on space and the tight radius of model curves [1625 mm] which if not allowed for will create a chunky appearance. The module the poles were positioned visually to provided a suitable appearance in the module. The elastic wire will require the addition of a stay at the last pole in each module. On the Spicers Creek the start was terminated in the styrene backdrop and in between the poles the loads cancel out.

Monday, 7 October 2013

Modular Layout

After much discussion with Ben & Geoff Small it was decided that it would be a good exercise to take the layout to the next level - well not really but the growing reality of the task to create a dream layout focused by creating Spicers Creek and with the small amount completed to date combined with a desire to have a operating layout and a very occasional exhibition layout created the new arrangement shown above.

One of the issues of all exhibition layouts is 80% of the infrastructure is not a public one and this is a real problem in O scale where the minimum radius is 1550 mm [5 feet]. This design seeks to maximize the public viewing for the layout footprint. The viewing area is 22.8 meters [74 feet]  with a 10.5 x 4.9 meters [34 x 16 feet] foot print providing 86% of the perimeter as viewing area with the back against a wall. The issue has to be if exhibition managers are willing to provide a location with all sides view-able and the back against a wall.