A site for my Model Railway Layouts: Barcoola. This is take on Tarcoola SA the junction between the Trans Australian Railway and the Central Australian Railway. A Town like Alice, my take on Alice Springs. Murray River Bridge, my model of the bridge over the Murray river.
Sunday, August 16, 2009
Barcoola MKII
As of this weekend Barcoola MKII has been sucessfully tested and shake down trials have been completed.
A total of 10 new scenery boards have been constructed, construction started in January 2009, and completed and delivered in August 2009.
A detailed description of the changes are as follows:
Barcoola MKII
Barcoola has been continually modified over the years and for the Caulfield exhibition we wanted to modify Barcoola into (hopefully) the final configuration, which would completely change the appearance of the layout.
The modification process was as follows:
• Hobsons Bay 2003, debut in original condition.
• Hobsons Bay 2004, built two additional “Lake Doug” boards to replace the original six foot version, a new fiddle yard board was constructed, to extend the layout the additional 6 feet.
• Sydney 2005, modified the bridge end corner board to match the profile of the Port August end corner board, so that transportation of the layout could be easier. This enabled us mount both corner board together (scenery to scenery) using segments of 12mm ply, thus limiting the potential for damage to the boards and simplify transportation.
• Adelaide 2007. Converted the layout to DCC, installed a set of crossovers in the fiddle yard and removed the Peco 83 #5 points at the eastern end of lake Doug. Installed Peco 83 #8 crossovers at the western end of Lake Doug. This arrangement enabled us to bring larger trains into Barcoola Yard, and increased the operational flexibility, including the full operation of the Tea and Sugar – and its East bound counter part the Bomber.
• Hobsons Bay 2008. Removed the original triangle board and replaced it with 2 foam core boards. This was done to increase the radius of the triangle from 24” to 35”. The use of two boards increased the available real estate for scenery, so we re-arranged the town to include more buildings. The back drop was replaced with a higher 600mm version. This also meant that the operators would no longer be able to sit in the middle of the layout, but have to mingle with the public to operate, which is what we wanted in the first place. The original small radius points and track layout was modified and replaced with Micro Engineering code 70 track and #6 points.
• Caulfield 2009. Barcoola MKII.
After the 2008 exhibition I started looking at creating a home layout which would also be able to go to exhibitions, this would not be a round and round layout but a complete operating layout. I wanted to redesign the complete layout construction techniques from the ground up, problem is where to start, so we looked at what we didn’t like about Barcoola and see if we could design out some of these faults.
1. 16mm ply is very heavy, probably was not the best idea to construct the fiddle yard from 16mm ply but it has never warped! The Ply constructed scenery boards were still heavy and then need to carry them up and down a spiral stair case. Any reduction in weight and size would be welcome.
2. Since the operators were now at the front of the layout, mixing with the public, shunting the yard required the yard shunter to reach over both the TAR and CAR mainlines to attend to shunting operations, this was not the most ideal situation. If the configuration could be reversed so that the yard trackage was in front of the main line tracks, this would solve this situation.
3. The corner boards were always a tad too long and one board which was built with 7 mm ply top would just slightly sag, which created a dip in the track work, this would only arise after a day or two of operation, this sag would in turn throw out the coupler alignment on the 86ft flat wagons, then this location would be the source of many a derailment.
4. The curves were built without a transition when an operator took the corner at a slightly higher than sedate speed some wagons wobble around. Trainsitions would be a good addition.
5. We could not find a room big enough to leave it set up all the time. We currently have it set up but split into different sections in one of our club members house, where it is incorporated into a larger layout (not everyone has a 84ft loft!). Each time we got to an exhibition where there was always some little problem which would not show itself until it was set up in its correct format for exhibition. This was frustrating to say the least, only being able to operate the layout in its full glory 3 days out of a year. Grrrrr!
6. After a while some of the boards held by the tool box clips, would slowly work out of alignment, as the clips would work loose and would not be able to provide much positive lateral control by themselves.
7. The Yard itself was always too short to take a full size goods trains, it would be more operationally interesting if we could put a full size train into the yard for visual crossing purposes.
8. Since we were using wireless throttles operators occasionally used the layout to rest the controllers on to while they shunted. It would be good to have some sort of holder so that the scenery would not be damaged.
9. The adjustment for the board heights relied on T nuts drilled into the ends of the legs, this meant that the boards always had to be lifted higher than required just to adjust the board height, this process was clumsy and created stresses on the boards there had to be a better way.
We then looked at what we could do to remedy these problems, It became obvious that we would need to replace the current corner boards, and if main scenery boards would be flipped 180Deg so what was the back of the layout was now the front and vice versa. This arrangement would put the mainline near the back drop and the yard trackage in the front, thus the operators have easy access to the yard trackage without having to reach over the main line trackage to attend to shunting. If we created the right track work on new corner boards the yard would be able to take full size trains. Replacing the corner boards this would account for items 1 (partly), 2, 3, 4 & 7 in one go.
We figured that if we constructed new corner boards as a light weight prototype for a future layout, Barcoola would then become the test bed for these new designed boards.
We then put pen to paper and Barcoola MKII was initiated.
New board design process.
To stop any sagging we looked at using 4 boards that would replace 2 of the current boards, to keep the weight down we used Formula R building grade insulation foam, this is high impact resistant and resists warping in short lengths, especially if the foam is laminated. Formula r comes in 30, 50 and 75mm thicknesses. To test out the capabilities of the foam we designed a few different boards two would be ultra minimal base thickness with a long fill, the others would be yard boards deep enough to comfortably fit tortoise point motors, in the vertical format. We have made some boards using this process 60mm thin without any reduction in strength.
The design we settled on could be best described as a 3mm MDF bathtub, with 12mm Ply ends were the boards interface each other. The interior is filled with foam.
Most layout boards are built with a base for the track and then all the wiring and space for the fold out legs are placed under the base. With this design the top is the bottom and vice versa.
This design has a number of advantages as follows:
• If the base of each board is flush, the wiring is protected at all times with holes cut into the base for access to important parts of the wiring.
• For transit we don’t require any custom made trailer to carry all the boards as we can load them into a trailer like Lego blocks, all self supporting.
• Dramatic weight reduction of each board, a foam board’s average weight is 8kgs verses 25Kg for a board made the traditional way with 12mm ply as a base.
• Able to create more dramatic scenery, as no space is dedicated to the frame as this has been subplanted by the insulation foam, therefore scenery can go below the track height without any problem.
• Any size or shape of board can be created using this process, the lay of the 3mm MDF base governs the shape of the board, everything is then built around this shape, no guess work required.
• You can see exactly the size of each board as a template, these can be test fitted into there final location prior to any construction, thus this limits any guess work and enables you to build board that you know will fit first time, every time.
• You can lay out track and buildings etc and test fit all these items before construction, test fit Track length clearances, point motors, track curvatures and clearly mark out their exact locations.
Construction process.
We started with 3mm thick 900 by 1200 sections of MDF that you can get from any hardware store. Transit of the boards relies on each board having a “mirror” image board, in this process the two “mirrored” boards then can be assembled facing “scenery” to “scenery” for transport, with a 12mm Ply protector ends installed on each end. These protector ends would keep the track ends from damage and turn each two boards into a self protected “Lego block”.
The final board sizes were cut out using a jigsaw, we recommend using Bosch Clean Cut for wood blades, these will give you a smooth cut edge every time without the need to clean up the edge, definitely worth the expense over standard blades. The boards were test fitted on a floor to ensure that all the angles are spot on. Directly onto these bases we mapped out the track, point, wiring routes, building at 1:1 size. Once we were satisfied with all the positions of track etc we traced out the track centreline, point locations and roads etc on large size tracing paper, this will make it easier to correctly arrange the track and roads after the boards have had the foam base installed.
12mm Ply ends were constructed, each with a 12mm lip or indent so that one board would support the next in piggy back fashion.
The sides of the boards are again 3mm MDF, the sides were cut thicker than required so that this would be easy to cut the edge of the final terrain profile. For any dead straight boards we in layed 12mm ply strips for additional strength. For support the bottom corners of any curved boards, we cut 23mm lengths of 12mm ply that had been kerfted about half way through. This would enable the ply to bend with the curvature of the bard sides while retaining strength.
The ends built remotely in batches and were attached each 3mm MDF base first, white glue was applied to the faying surfaces we then used an electric nail gun, to position the ends quickly. Small triangles of 12mm Ply were added to the ends and the 3mm MDF base for added strength. Using the nail gun we attached the 12mm ply strips to the inside of the 3mm MDF sides. We then attached the MDF sides to the 3mm base.
We now had what looked like 10 strangely shaped wooden bath tubs.
Access holes were cut into the bases using a jigsaw for things like wiring terminal blocks, Point motors, Switch-its, reversers, attachment locations and lighting attachment points. Use circular holes as any sharp corner of a hole will create a fatigue point and encourage crack prorogation.
Legs were constructed using 19mm by 42mm pine timber, they were a standard gate format. This means two legs attached together via two hinges. We have found that three point legs are much more stable than two point legs. The legs are not permanently attached the boards.
The legs were not fitted with T nuts, we found that after a while they became loose in the leg base and would eventually fall out in transit, even if they were “liquid nails” glued in place! Height adjustment for these boards would be accomplished using small MDF shims, which could be added between the boards and the legs as required. This arrangement required less work to accomplish an adjustment, but also would not stress the boards as much as the T nut method which would require you to lift a board up at the leg bottom adjust the base and put it down again which put a lot of strain on the operators and the board joins. This would solve problem number 9.
The boards were set up in their required format, and clamped together. Tool box clips were attached to the board sides at each join. 19mm holes were then drilled though the 12mm ply ends and a piece of dowel was attached to the “male” side of the boards. These pieces of dowel would now align the ends and the height of each board. The tool box clips are only used to physically hold the boards together. This would solve problem number 6.
Depending on the board type we used a combination of 50mm and 30mm Formula R foam for the track base. For the bridge embankment boards we used a 50mm base which housed the wiring and doubled as the floor of the river. The embankments were made from sections of 30mm foam laminated to gain the required height. The formula R foam can be cut easily with a jigsaw using a clean for wood blade, this type of blade reduces the amount of loose particles when you are cutting, and we recommend you use this type of blade for this type of work.
The tracing paper we made the track plans on was then laid over the board so that we could determine the shape of the embankments. You will notice that most modern permanent way design has a very wide base where there might be room for a maintenance vehicle to drive without driving on the track. We accommodated for this extra width when we designed the embankments. The edges of the embankments were cut at 45deg, most jigsaws allow adjustment to 30 or 45deg. When we were happy with the size and shape of the embankment we cut wire access holes to align with the holes we previous cut into the boards, this would mean that our dropper wires only had to travel though one layer of foam.
Laminating the foam greatly increases the strength, we used a thin layer of acrylic sealant to cement the layers together.
For sections of the embankment, we used a hot wire cutter to put vertical erosion tracks in the embankment sides.
Any foam that was not supporting track we used white “beaded” foam. This type of foam can be found on just about any housing construction site on the planet. Some of the materials arrive on site protected by this type of foam. Most builders are more than happy for you to take it off their hands as otherwise they would have to pay to dispose of it.
With the foam scenery and track bases “roughed” in place, a marking pen was used to trace around the ends of the foam where it meets the 12mm ply ends. A jigsaw was then used to remove the unwanted 12mm ply so that the ends conformed to the shape of the scenery.
When everything was finally roughed in, the wiring was installed.
Wiring.
For the electrical wiring between the boards we wanted something that would not project out from underneath the board. We had not previously had damage occur to the wiring before but it has always been a real point of concern. The design we came up with was to use Jaycar Auto Electrical connectors, they are available in 4, 6 and 8 way connectors, they come pre-wired with a male and female connector at each end and about 400mm of lead between them and wires are good for at least 10amps. The connectors were cut into sections of Male and female ends, these were then attached to a 3mm MDF square of 140mm. A Ply and MDF clamp was fashioned to hold the connector in place, electrical silocone was applied to any gaps to hold the connector in place, and a terminal block was screwed to the other end. Twelve of these connector “plates” were made, they would be installed connector down into the bathtub of each board. Between each connector two core wire was installed in channels previously cut into the foam, various terminals blocks were located in strategic hole locations around the board so that they could be mated to the track droppers later.
2 of the leads were used of track DCC power, and we used 10amp two core cable for this. The other 2 wires carry the accessory of Switch-it power, only 12awg wire was used as it is of low amp draw.
As required we used a hot wire foam cutter to get the particular shapes and transitions of landscape that we were after. Casula hobbies market a really good foam cutter, it is big enough and robust enough to do just about any job, highly recommended. Drains and such were created using a soldering iron.
When each board was wired, the track base foam was then sandwiched using acrylic sealant.
Now the next bit seems a bit weird but we then added base scenery, using more acrylic sealant, we attached the various sections of white “beaded” foam to the track base.
After the sealant had dried, we used a non circular sander to blend all the edges of the foam and create smooth transitions from board to board. Also Any imperfections in the track base were sanded, so that the track would have a very smooth and stable base.
Then all the boards were painted a base colour to represent the desert scenery, we used Bristol brand burnt sienna. It’s a sort of a dark orange base colour, that if exposed will not be noticed. Painting the board with white glue (except in the future track locations) we then added various sifted grades of sand collected from the area. Then the whole board was sprayed with a water and detergent mix, to ensure the all the glue gets all the sand.
Reinstalling the track templates, we glued strips of cork to mark the track location, using acrylic sealant. Most mainlines have two thicknesses of cork to represent higher ballast base of a mainline. The yard trackage has only one thickness or none at all.
Once the glue dried, a sander was again used to blend out any imperfections in the cork track base, it was also used to gently transition Mainline track base to yard track base. The cork as layed right across all board joins, this will be cut once the final scenery has been finished.
Map pins were used to hold the cork in place while the sealant dried.
The track was test fitted, we used a various different brands of track for experimentation purposes, the mainline was laid using Atlas code 83 concrete track. Mainline #8 points were Peco code 83, with the exception of one Walthers Y point. Smaller points were Mico engineering #6 code 70, yard trackage was Mico Engineering code 70.
The new location for the mainline crossover at the Port Augusta end, required that the #8 points had to be slightly curved. To create the subtle curve, we used a little trick to “bend” at straight point. By removing small spacer sections under a point we can use these gaps to slightly bend a point without destroying it. We used the same technique to increase the bend ratio on a Peco code 83 curved point for the new triangle board.
Micro engineering and Walthers points as these come DCC ready and will not create a short if the loco happens to drive back through a point set against the locomotive. We modified the Peco electrofrog points by isolating the frog using a dremel and soldering droppers the closure rails and keeper rails. All points had droppers soldered to the base of their rails prior to installation.
The Points were test fitted in the location and holes for droppers were drilled through the cork and the first layer of foam. Track was then reinstalled, and droppers fed through the foam.
The track was “glued” to the cork using acrylic sealant, in this fashion whole sections of trackage could be laid at once. Map pins were used to hold the track in place while the sealant cured.
Each section of track has a dropper or is at least only one joiner away and that joint was soldered to ensure good electrical connections and reduce any voltage drop.
At this point track sections were tested to ensure that continuity of the track worked ok, before final scenery was applied.
The working mechanical sections of each point were masked using magic tape. Then the yard trackage was painted a rust and rot mix. The mainline was painted a slightly more diluted version of the same. Ballasting was accomplished in the traditional manner as was the rest of the scenery. The roads were cut from 600GSM card available from Office works. Painted an ashphalt colour, and cut to fit as required. The crest of the road was accomplished using a strip of cork under the centre of the road, the card was then attached to the board using acrylic sealant.
The only items we have not been able to fix are items 1 and 5, so we are happy with the new version of Barcoola, and hope that you have got something out of these as we have.
The MKII boards seem to have been successful experiment so its now time build the next layout, a little bit further north this time, so stay tuned.
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