Not in OO but in HO. I was young and poor and couldn't afford what was
on offer, even a kit turntable cost almost two weeks' wages! It was an
"armstrong" turntable, ie, one rotated by men pushing on a pole fastened
to the end of the bridge. This was used surprisingly often on small
tables at the ends of branch lines. With a small engine, well balanced
on it, it took very little effort to turn the bridge, which rode on half
bogies riding on a circular pit rail.
I found that the trickiest part was the turntable pit, but I used other
people's techniques for this, and it worked out well. I built the bridge
substructure first: cut a piece of wood the right length, somewhat
narrower to allow for adding "girders" on the side, and somewhat
shallower to allow for the track on top. I drilled a hole first, then
cut it so that the hole was as close to its centre as I could measure,
and glued a washer on the bottom to act as a bearing. I inserted a piece
of 1/4" steel rod I happened to have (the hole was sized to be a tight
fit.) A chunk of very large nail could be used.
I drew the turntable pit, tracks, and roundhouse locations on a piece of
plywood and cut it to fit into and against the baseboard of the yard. I
drilled a hole at the centre of the turntable pit to clear the centre
pin of the bridge. I glued a washer there to act as a bearing, dropped
the bridge into it, and used it as a compass, by taping a sharp nail at
each end, and turning it. The two circles differed a bit, so I sanded
the longer end, and redrew the circle, and repeated this until both ends
produced the same circle. Then I taped a thick pencil on the end, and
drew another circle about 1/4" outside the scratched one - this was the
diameter of the pit.
Next, I fastened a piece of plywood underneath where the pit would be,
using _unevenly_ spaced screws to ensure alignment later. I used the
hole above as a guide to drill a hole through the lower piece, and
removed it. Then I cut the turntable pit out as carefully as possible,
which wasn't easy with a handheld power jigsaw. I refastened the lower
piece, inserted the bridge, and drew another working circle just inside
the pit walls. I used this line as a guide for gluing "used ties" to the
wall of the pit. That's how the prototype lined the pit wall. If you
want a "concrete" wall, you'll have to apply some kind of goop to the
wall, and use the a bit of wood fastened to the end of the bridge as a
I then glued half length ties all round the outer edge of the pit, and
glued and spiked two half circles of rail in place. I did not build a
half bogie to support the bridge, but instead used two pieces of springy
brass, which rode on the pit rails, and which were hidden by the girders
glued to the sides of the bridge.
The two pieces of rail in the pit were wired to right and left approach
rails respectively, the brass wipers ditto to the bridge rails. Thus,
the turntable bridge became a reversing switch, very handy. I added
details, paint, weathering, and so on, and it looked just fine. I
planned to motorise it eventually, but didn't, just used my fingers and
a proper armstrong pole to turn it around, as the table was close to the
front of the layout. It's long gone, of course, but it worked.
This can still be seen at the Didcot Railway Centre. Part of the Open Day
routine is to run a GWR 7F 2-8-0 up to the table, and turn it by hand. On
some occasions they use the rotating crank handles, on others they just push
the bars. A 7F is not small, and though I've watched it dozens of times, I
still can't work out how they shift that weight.
(I'm usually watching from the restored saloons Queen Mary and Princess
Elizabeth, while enjoying a leisurely afternoon tea. It's amazing how one's
digestion is greatly improved by watching other chaps putting their backs
into the job!)
Of course, because there's so much more room.
Here in the Toronto-Montreal corridor we have ~120 car freight trains
(e.g. double-stacked containers or 3-decker auto carriers) and inter-city
passenger trains with as few as 3 coaches (but the coaches are bigger!)
American bankruptcies are bigger, but better? Think of Enron. Mind you,
I shouldn't complain, the Sarbanes-Oxley Act, Congress's knee-jerk
reaction to Enron, is giving me plenty of no-brainer-type work to do (I
suppose that's because American executives generally have no brains).
(No smiley, because I'm serious).
OO in the garden http://www.yddraiggoch.demon.co.uk/railway/railway.html
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