Manual Points by WIT


This section covers the construction and installation of mechanical lever frames which are not prototypical in appearance but do move in a manner not dissimilar to the prototype. Also covered is the associated “Wire in Tube” (WIT) operation and installation. The photo below shows some lever frames in position near the proposed Carriage Works in the early stages of my layout. Four of these control single points and two control facing points (crossovers).
In this post:-  “Point” = “Turnout”            “Sleeper” = “Tie”The lever frames are two assemblies – the frame mechanism itself and the housing.

HOUSING:

The housing was fabricated from 2mm ply and a small block of wood.

FRAME:

The frame is based on a standard aluminium section plus some metric nuts, bolts and screws, an electrical connector, and a PVC and brass welding wire handle. I have some sketches – if there is any interest.
This frame is for a single point
This frame is for a crossover with one wire pushing and the other pulling. Component “A” is one of the brass terminals from a piece of Terminal Strip shown on the right. That makes it a very economical solution. The visible screw allows adjustment of the position of the point. The second screw in the same brass terminal piece allows it to be screwed to the handle with a small countersunk screw.
The aluminium mount is held to the fascia by a single screw through the bottom hole. The top hole receives the WIT.
This is the tube I used. It is the outer part of a Bowden cable used for the gear shift on a bicycle. A bike shop should be able to sell you a metre or two.
Test assembly – then glued with PVA
A single lever frame with the operating wire bent at right angles.
I use 1.25mm dia piano wire which needs a powerful hardened cutter as shown at the bottom of the photo above. In this install the WIT was fitted through a hole drilled straight to the nearby point.

For this crossover (above and below) near the front fascia of the layout, there was no room to fit a WIT the normal way. The frame directly controls the rearmost point by the bottom wire on the frame and this wire runs directly under the plywood mounting for the bellcrank (white above) and come up through the throwbar as can be seen below.
There is a very short piece of tube to hold the wire in place near the point. I glue these in with PVA.
In order to throw the second point in the crossover, the top wire from the frame operates a bellcrank which changes the direction of the pull (so that it is parallel with the fascia) and operates a second bellcrank for the front point.

To get some necessary adjustment between the 2 bellcranks, fit one of the brass electrical connectors (descibed in the picture 5th down from the top of this post). The interconnecting wire then needs to be 2 pieces – one long one and a shorter one near one of the bellcranks – as above.

The photo below shows the setup for the other point. I had to drill a hole right through the fascia to get the short piece of WIT to the throwbar. Again, the bellcrank is mounted to a thin plywood plate which will sit above the throwbar wire. You can buy these bellcranks from Model Aircraft shops.
The normal method of installing facing points with WIT is shown below. In this example originally there was only a single point and the trench for the WIT is still visible to the left. In changing it to facing points the frame was relocated; swapped to a double wire type; and new trenches laid for the WIT.

This jig is used to make sure the WIT hole(s) and the mounting screw pilot hole is in the correct position.
Here is an earlier version in use.
To cut the trenches, pin the tube in place over the best and smoothest path. Run a fine marking pen along each side of the tube.
Hand held Dremel and vacuum cleaner in use the cut between the lines.
This cutter does the job well. The vacuum is very necessary especially in the expanded foam unless you want to generate a snow storm!
This template locates the cut-out needed to accept the microswitch under the point.
The red lines are used to align it to the rails as the microswitch is installed off centre. That is explained in my post on MODIFYING PECO POINTS FOR DCC.

In some ways I preferred the manual point operation as it is more appropriate for my 1960s layout where the train crew or shunters did much of the groundwork. However the change to servo control does allow simpler use of area conrol panels and some likeness to a signal box diagram.

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Rick Fletcher

Born in the steam era and developed an interest in railways when given a clockwork Hornby "set". Surrounded by steam when travelling to school (by train of course) and holidays were always by steam train as we had no car. How lucky was I?

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