Do-it-Yourself Turntable
The prototype of this turntable is located
in Kokkola, Finland (picture above). Commercial turntables are
expensive and not suitable for Finnish modeltrain layouts, so
the only way is to do it yourself. The building started with a
flower pot made by company Orthex Oy, which happened to be useless
in my garage and was about the right size. The actual table originates
from Märklins old arched metall bridge. The turning mechanism
includes two ball bearings and a shaft pipe. The motor and the
gears are from an old video recorder. I have modelled the parts
with Pro/Engineer -CAD-software and they have been machined of
aluminium. If somebody wants to take a look at the drawings, they
are here. "Real"
H0-drawing of Finnish turntables are published in Finnish model
train magazines Pienoismalli-lehti
issues 8/2003 - 1/2004 and Junat-lehti issue 2/90.
The building starts with Orthex
flower pot 483-250
The pot is cut to a suitable height
and the pot is inserted to layout table.
The geared motor (1:60), worm screw
(1:20) and reduction gear (1:5) from an old VCR are installed
to the bottom of the pot. The total reduction ratio is 1:6000,
which makes the table to turn slow enough. ( 2min/360°). The
operating switch is connected to a relay so, that in STOP-position
the motor poles are shorted and the motor stops very quickly.
With this "electronic brake" the table stops accurately
to the right position without any locking systems.
Turning mechanism installed. The
shaft is a pipe to be able to connect the middle contacts in the
rails. The rails are connected the with aluminium mechanism (ground).
Fitting the table.
The rail on the middle floor is
a half of a N-scale straight track.
The stone structure is made with
Darwi-modelling paste and coloured with Woodland Scenics Earth
Color paints. The middle floor is covered with a fine sand and
glued with Woodland Scenics Scenic Cement, which dries up totally
invisible unlike common white glue.
The sides and beams are also added.
The sides are 1mm aluminium sheet and beams balsa wood.
The diagonal supports are Plastruct
3.2mm H-profile (90543) and the floor boards balsa wood. In the
future more details will be added such as signal plate and locking
system with wires.