| This will help you when it is time to center the turntable
in the opening. Remove the pit floor. I know, you just installed it but
the reason will become clear very soon.
After the pit floor has been removed, use a saber saw to cut out the
square, NOT the circle. This will allow you to do the work at
your workbench instead of under the layout.
While you may be able to cut a clean vertical circle, it may be worth
the expense to have a cabinet shop cut the circle for you so you will be
sure to have a clean vertical pit wall. Sometimes a jig saw blade will
flex producing a pit wall that slants and is not at a 90 degree angle to
the sub-roadbed which will cause you problems later.
After the hole is cut, temporarily re-attach the pit floor and draw
around the opening where the pit wall meets the floor. Measure the
diameter of the end of the Plastic (CPVC) plumbing pipe then drill a
hole (using the center hole in Figure 3) the to allow the CPVC pipe to
pass through the pit floor. The Atlas turntable has a screw in the exact
center of it�s floor. Center your compass on this screw and draw a
circle on the floor the same size as the end of the CPVC collar. Cut a
small notch approximately 1/8� square in the wall of the CPVC collar
at one end. Measure and cut 2 pieces of #20 wire 6� long. These wires
will pass through the notch and extend up through the collar and CPVC
pipe and through the Bridge floor.
Leave the wires at the 6 inch length for now as it will make assembly
MUCH easier. Solder 1 wire to each rail in the Atlas Turntable floor,
place the wire through the notch and glue the collar to the floor of the
Atlas Turntable making sure it sits centered in the small circle you
drew with the compass. Pass the wires through a 3� length of CPVC pipe
which will be used to connect the Atlas Turntable to the new Turntable
Bridge. Select the bridge of your choice for the new turntable. If a 9�
table will meet your needs, an Atlas Through Girder bridge turned upside
may work well for you. If you are making a table larger than 9� build
the bridge from plastic, wood etc. If you are using an Atlas Through
Girder bridge, glue another PCV collar to the center of what would
normally be the top of the bridge floor (where Atlas puts the rails and
guard rails.) The real bottom of the bridge has a casting mark at the
center of the bridge. Drill a VERY small hole through this mark to help
you center the CPVC collar.
When the glue has dried, re-attach the pit floor, test fit the CPVC
into the collar on the Atlas turntable, pass the CPVC through the hole
in the pit floor and test fit the bridge onto the CPVC pipe. At this
point your bridge will be too high and that�s OK. Measure the distance
from the bridge floor to the surface of the sub-roadbed. Record this
measurement and make 4 spacers of the same dimension from scrap wood.
Turn the entire assembly upside down on the workbench and glue the
spacers between the turntable and the plywood sub-roadbed so you may
attach the turntable to the spacers using the mounting holes provided in
the turntable.
Attach the turntable motor to the turntable then attach the turntable
to the spacers using wood screws. Hint: the longer the CPVC pipe, the
more room you have to work on the motor for belt replacement etc after
the turntable has been installed. You may wish to make the pipe 4�
instead of 3�. Before you glue the CPVC pipe to the bridge and
turntable floor�s CPVC collar, remove the bridge and apply the surface
of your choice to the pit wall. I like H&R�s styrene sheet called
�Pebblestone� I cut pieces tall enough the cover the wall and try to
make sure the joints are placed where they are the most hidden from
view. I paint it all over with raw umber acrylic paint then paint some
of the �stones� with Burnt Sienna. This will produce a strong color
contrast that will be toned down by applying a wash of acrylic gray
which is gently wiped with a piece of paper towel. The gray will
simulate mortar and tone down the color contrast. You may wish to
install a ring of rail at the base of the wall to simulate the rail that
supports the end of the bridge. I used 2 lengths of square styrene again
hiding the joint from view and glued them to the pit floor at the base
of the wall. You may put short pieces of railroad tie on the styrene to
mount the rail ( I used a length of small styrene painted a rusty color
to �simulate� the rail. From any distance beyond a few inches your
brain tells you it is a rail as that is what you expect to see. You may
need to make some minor adjustments to the ends of the bridge to clear
the new pit-rail ring. Test fit the entire assembly one last time and
connect a power pack to the turntable motor. Make sure the bridge turns
freely within the pit. Paint the pit floor gray and stain it with washes
of black to simulate grease or apply white glue to the floor and
sprinkle some dirt ( I used some from Colorado) to simulate a dirt
floor..
Check again to make sure the new surface on the pit floor does not
inhibit the movement of the bridge. If everything is working correctly
remove the bridge and glue the CPVC into the collars after passing the
wires through 2 small holes drilled beside the rails on your bridge
This is why I suggested 6� wires. It makes the bridge placement
MUCH easier.
When the glue has dried, Track Alignment - It is virtually impossible
to be 100% sure the track is straight, so here is an alignment tip. Spin
the table until the bridge is in line with the approach track, glue ONE
end of the track to the bridge floor. Spin the table 1/2 turn and align
the track to the approach track. Now you can install the tracks to the
engine house and they will be in alignment with the rails on the bridge
floor. Trim the wires and solder to the outside of the rails. Apply the
railings of your choice to the deck of the bridge (you don�t want your
crew falling off the bridge into the pit.)
Connect your power supply to the track power terminals on the Atlas
Turntable and test to be sure the polarity matches the track approaching
the turntable. If it does not match, simply reverse the wires at the
turntable connection screws. I purposely left out the part about
painting and applying decals (if desired) to the turntable bridge. You
may finish the bridge in any manner of your choice. I applied a scribed
siding floor and painted the sides of my bridge with Floquil Old Silver,
then stained it with a wash of India Ink mixed in rubbing alcohol. To
suggest age I applied some subtle rust streaks using chalk pastels.
Your new turntable will have automatic indexing and polarity
switching supplied by the Atlas turntable which has been hidden by
your cosmetic enhancements. When someone asks you �What kind of
turntable is that?� Get ready for a look of shock when you reply �Atlas.� |
