CONGRATULATIONS !
THE
TORTOISE
SLOW MOTION SWITCH MACHINE REPRESENTS THE
VERY LATEST IN HIGH TECHNOLOGY DESIGN. UTILIZING A
PRECISION GEAR-DRIVE MECHANISM COUPLED TO A MICRO-
CURRENT DRAW MOTOR WHICH SAFELY STALLS OUT, CUTOFF
CONTACTS AND COIL BURNOUTS ARE A THING OF THE PAST. THE
FULLY ENCLOSED CONSTRUCTION WITH OUR ULTRA-SIMPLE
MOUNTING AND LINKAGE (INCLUDED) AND THE SIMPLIFIED WIRING
WITH AUXILIARY CONTACTS STANDARD COMBINE TO MAKE THE
VERY FINEST SWITCH MACHINE AVAILABLE AT ANY COST.
CONTENTS OF BOX:
(1) TORTOISE
(1) Molded Fulcrum
(1) 3.5” Spring Wire
(1) 3/8” x #4 Phillips
Retaining Screw
LAYOUT PREPARATION
The TORTOISE is designed to mount under the layout with the spring wire transmitting the linear motion
through the layout board and roadbed to the turnout throwbar. Turnouts should be checked for free
movement of the points and a clear area under the layout for mounting the machine. Although the
TORTOISE is extremely forgiving in mounting, a turnout that binds will still not switch smoothly. It will be
necessary to provide a hole or slot directly under the throwbar. This hole is typically located between the
rails, but may be outside the rails, if desired. The size of this hole should equal twice the the total turnout
throw (1/4” works well for HO and S). In addition, a small hole will have to be drilled in the throwbar for
the spring wire to pass through. Some turnouts have a rivet in the throwbar which can be used for this
purpose. If the turnout is already mounted, we suggest drilling a small (.032” - .040”) pilot hole through
the center of the throwbar and down through the roadbed and baseboard. Next determine the total
thickness of the roadbed and board and mark the 1/4” bit with tape or use a drill stop. Then, using the
pilot hole as a guide, drill up through the base and roadbed, being extremely careful not to break through
and destroy the throwbar. It may be possible to flex the throwbar away from the roadbed slightly to help
prevent this. Finally, use a hobby knife to remove any remaining roadbed and to clean up the hole.
TORTOISE PREPARATION
The 3.5” x .025” spring wire provided with the TORTOISE is suitable for layouts having a total roadbed/baseboard thickness of
one inch or less. If your layout thickness is greater than 1”, you will have to substitute a suitable length of .025” spring wire for
the one provided. If greater tension on the points is desired (for O Scale and larger), you may substitute a heavier gauge wire.
The output arm will have to be drilled out with a suitable diameter bit held in a pin vise.
CAUTION: DO NOT USE A POWER DRILL!
1.
Prepare the spring wire by gripping it with pliers 1/8” from one end and make a sharp 75-80 degree (nearly right angle) bend.
At a point 3/4” away from the initial bend, make an additional 15 degree bend in line with the first. Figure 1 is full size and
may be used as a guide.
2.
Using a #1 Phillips screwdriver, carefully thread the small phillips head retaining screw into the large hole in the throwarm.
DO NOT PUSH ANY HARDER THAN NECESSARY ON THE ARM!
After the screw bottoms out, remove it. It will be
reinstalled after the TORTOISE is mounted.
3.
Slide the fulcrum into the fulcrum rails on the front face of the TORTOISE so that the larger openings of the tapered pivot
holes face the bottom.
MOUNTING
Cut out the template and use a punch or hobby knife to make a hole in the center of the large black dot. The TORTOISE can be
mounted off centerline if necessary for special clearance applications, in which case one of the two dotted alternate circles
should be used. (This changes the geometry of the spring wire, though. Request Application Note AN-6000-01.) Tape the
template to the underside of the layout with the hole you just made centered over the 1/4” hole previously bored through the
layout. NOTE: The large arrow should be parallel to the rails. Drill pilot holes for #4 wood or sheet metal screws at the four
points indicated (3/32” or #42 drill bit). Remove the template and fasten the TORTOISE to the layout with #4 x 1/2” wood or
sheet metal screws. The hole in the fulcrum should be centered directly under the hole in the layout.
A
LTERNATE
M
ETHOD
:
Use the template as above, but instead of drilling pilot holes, merely mark their location with a punch or
nail. Remove the template and sand the wood lightly to provide a clean surface. Spray the area with lacquer to seal the wood.
Let dry overnight. Apply double faced foam tape (available at hardware stores) to the entire top surface of the TORTOISE.
Remove the backing from the tape, and using the punch marks as locating guides, press the TORTOISE into position. Rock the
TORTOISE in all directions to ensure a good bond. Finally, run a bead of silicone RTV (bathtub caulk) around the two mounting
flanges against the layout. Allow to cure overnight before proceeding.
CAUTION: ALTHOUGH THIS METHOD PROVIDES
ADDITIONAL SOUND DEADENING, THE LONGEVITY OF THE TAPE/SILICONE BOND IS LARGELY UNTESTED, AND LONG-TERM
SATISFACTORY RESULTS CAN NOT BE GUARANTEED.
TM
WIRING
Connections to the TORTOISE can be made by inserting light gauge wires through the holes in the printed circuit board. Solder the wires to
the pads using rosin core 60% tin, 40% lead solder (available from Radio Shack) and a small 25 - 35 watt pencil type soldering iron.
WARNING: DO NOT USE A HIGH WATTAGE SOLDERING GUN. DAMAGE TO THE PRINTED CIRCUIT BOARD IS NOT COVERED UNDER WARRANTY.
We recommend locating an 8 position terminal block near the TORTOISE and running the wires from the TORTOISE to it. In this way, any
changes in wiring can be made at the terminal block without having to desolder connections on the board. A more costly option is to utilize a
10 position printed circuit board edge connector (available from electronics’ distributors -
request Application Note AN-6000-04 for
specifications and ordering information from one mail-order distributor
) which will simply plug onto the TORTOISE circuit board.
The connections on the circuit board are numbered 1 - 8 from left to right. Connections 1 and 8 go to the motor. 2, 3 and 4 connect to one
of the internal SPDT auxiliary switches which can be used to power the frog, signals, etc. In similar fashion, 5, 6 and 7 make up the other
SPDT switch. These auxiliary switches can
switch
a maximum of one (1) amp of current (they can safely carry 4 amps on each contact set)
and can switch either AC or DC loads. If you need to switch heavier currents, parallel both sets of contacts or you may connect a relay to the
output. Figure 2 shows the internal connections and switch configuration of the TORTOISE. (
Request Application Note AN-6000-02 for
detailed wiring diagrams of turnout frog, relay and signal wiring.
)
F
IGURE
1.
