Page 11 - May June 2012

I decided to mount DCC throttle panels to the sides of one of my boards. This is optional. The specification allows them to be temporary additions on operating days if you prefer. I recessed mine to avoid transport damage. I cut rectangular holes in the side of the board and glued pieces of scrap 9 mm ply inside this to carry the panel and to restore some strength to the side. You can see the back of one of these openings in Photo 6. I cut the necessary rectangular slots by first drilling holes at each corner, cutting between these by hand using a coping saw and finishing off by filing.
Before assembly, I marked the various plywood pieces for the screws that hold everything together. Those on the long sides of the top are 19 mm in from the edge; on its shorter side they are 9 mm in. Those near the top edge of the sides are 10 mm from the top and those on each end 9 mm in from the ends. I spaced most of these screws around 5 inches apart, but this dimension isn’t critical. It is important that the screws through the top aren’t exactly in line with those through the sides, though. Otherwise you will find that when you drill the holes for the top screws the drill will hit the already-in-place side- screws, and break off in the hole. I’ll leave you to work out how I know this.
Board assembly
Assembly starts by screwing the softwood battens to the sides. Photo 3 shows a batten clamped in place and the screw-holes being drilled. It is important that the top of the softwood is exactly level with the top of the sides. The clamps allow you to adjust this and then forget about it while you drill the holes for the screws. If you don’t own enough suitable clamps you may be able to borrow them from your local NMRA group, which is what I did.
I used a combination bit to drill the holes for the screws. You can see this in Photo 3. It drills the pilot hole in the softwood, a clearance hole through the ply and countersink for the screw all in one go. I bought a set of these from Screwfix. They are sized for different screw sizes. This job needs a #6. If you don’t have a combination bit you can use the appropriate-sized individual drill bits (2 mm and 4 mm plus countersink). Use 1" × #6 (25 mm × 3.5 mm) countersink-head woodscrews for assembly.
Photo 3: Joining the batten to the side
Photo 4: G clamp and mitre clamp used to clamp side to top
Before fitting the second side, I fitted the two 18 mm ply ends. It is important that the ends are at exactly 90 degrees to the top. If not, there will be a slight angle between the tops of adjacent boards when they are clamped together. The top-to- side angle is the only really critical item in the construction, so it’s worth taking your time and getting it right. I used a combi- nation of G-clamps and mitre clamps to align everything and then double-checked with a square before drilling, as shown in photo 5.
Photo 5: Fitting the 18 mm ply ends
The final step to complete the board is to add the second side. Photo 6 shows how I clamped this in place before turning it over and fitting the screws.
Photo 6: Clamping the second side
Legs
The first step is to add the leg-guides to the top. These were shown in Photo 2. These are the same material as the legs (44 mm × 20 mm softwood) and extend from the underside of
With the sides and battens screwed together, the next step is to join one side to the top. To hold the top and sides together I used a combination of G clamps and 90-degree “mitre clamps”, as shown in photo 4. The mitre clamps hold two pieces of wood at a right-angle. You can see their construction from the one in the foreground. Normal G-clamps alone can be used for this job but the mitre clamps make life easier. Again, mine came from Screwfix. They look pretty fancy, but two of them cost less than one decent-quality freight car. Make sure that the ends of the top and sides line up exactly before drilling and screwing the top in place.
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