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Trevor Lloyd-Lee's PYTHAGORAS Folding-Baseboard Design
While working in the USA for six months, I was an honorary member of the local model railroader club.
It was a wonderful experience to see first-hand how Americans tackle the modelling of railways -the brief
answer is "in a big way". Many of the layouts I was privileged to visit occupied the whole basement and
frequently quadruple-headed trains of fifty or more bogie freight cars were operated. We Brits seldom double-head
our trains and consider ten coaches a long rake.
I took with me a small collection of 3mm-scale stock, materials and tools (Heathrow Airport security zoomed
in on me immediately after the hand luggage passed through the x-ray machine and the interrogation which followed
would make a story in itself!). I decided to build, in my hotel room in six weeks of evenings, a British-style terminus
to fiddle-yard minimum-space layout. The most important criterion was how to get it back to the UK at the end of my secondment.
I spent a lot of midnight oil and scrap paper getting nowhere before the obvious hit me.
Enter pythagoras, who still plagues schoolchildren with the square on the hypotenuse. I needed a transportation box,
and a diagonally-folding baseboard would create a strong rectangular tube. Everything that mattered would be inside,
with no loose pieces to leave behind. But would it work? The more familiar baseboards without a backscene fold easily
on raised hinges to form an open-sided flat pack. At this point, alot of questions were asked:
- what if the backscene were not removable?
- what if it were a strong, integral part of the baseboard?
- what if the hinges operated on the diagonal?
I felt that a solution was in sight, and that it would work providing the diagonal was at 45°
and the folded shape that special rectangle called a square.
Figure 1 shows the basic cross-section looking from the hinge joint, drawn showing
the diagonal hinge line and a second baseboard in the folded position. The folded dimension
of my layout is eleven inches square, plus the framework of 2in x tin softwood. Each board
is three feet long. One slight limitation is the available height for scenery and structures.
Anything below the hinge line should be okay, but scenic items which extend above it must
coincide with low ones on the other board. My fiddle yard is open-sided towards the operator
and hidden from the viewing side by a sloping cover running forward, just clearing the station
building roof and stopping clear of the platform. Similarly, the road which uses the overbridge
must finish clear of the track next to the platform. The semi-circular platform canopy extends
beyond the hinge line, but when folded it fits in the space between the tunnel-mouth end of the fiddle
yard and the tall bracket signal.
The inner and outer baseboard ends were each cut in one piece from some offcuts of thin marine ply.
Half-inch ordinary ply would probably be okay. Figure 1 shows details of the inner ends, which are identical,
and the way layout features need to fit when the boards are folded. The outer ends can be simple triangles
which meet on the hinge line when folded. The general slope of the landscape is important in fitting this
three-dimensional puzzle together. On my layout the land slopes downwards a bit from the backscene to the front
and slopes lengthways from farmland over the tunnel entrance and fiddle yard to about an inch high at the baseboard joint.
The land continues to fall on the station board so that the last bit of track to the buffer stops is on a small embankment.
The aim is to create the effect that the land was there before the railway came.
Figure 2 shows a hinge with a removable pin used to secure the boards when folded. It also shows how I profiled
the outer ends (cut from one piece on a band saw) to follow the shape of the embankment and create an interlocking
profile to increase rigidity during transportation. This has two further advantages: the end of the fiddle yard is
completely blanked off, and the open end of the station board will allow the railway to continue on to another pair
of boards whenever I feel like accepting the challenge.
