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.

Rail Joins at Lifting Section

To make sure that joins in lifting sections are in alignment care needs to be taken.
The following method works well on Brolgan Road.

This is the latex carpet adhesive used to hold all the track, points and underlay in place. Preparing the join on the entry lift-up-flap a small section of cork was added to provide a stiff base. The PCB sleepers are soldered in place and the track suspended in the air with paddle pop sticks. The Tee pins allow the track to be aligned; then raised for the glue; and lowered into position.
The track has weights added until the latex cement sets. Note the plywood pieces to align the rail joins. Short pieces are great for keeping curves aligned where flex track joins.

Note: it would be better to use 5 sleepers instead of 3 to give a bigger bonding surface. Epoxy on these sleepers was a better option.

Three sleepers were removed and PCB replacements soldered in place. The middle of the sleepers sanded away to insulate both sides. The track is code 75.
When the glue sets, the join line was cut with a razor saw. Slow and tedious. The latex was not up to the job on these sleepers and I now use epoxy.

Modifying Peco Points for DCC

A Peco Electrofrog point modified for DCC is shown below. I have added the microswitch to the right which changes the polarity of the frog as the point changes. The microswitches were about 50c – $1 on eBay and are activated by the push rod controlled either by:
mechanical point levers
or by servos.
On this page “Point” = “Turnout”  / “Switch”       “Sleeper” = “Tie”The microswitches need to be small – these are 20mm x 10mm x 6mm thick (body size)

These were the microswitches I used but …
… the longer arms on these may have been better (can be trimmed)

The first step is to attach the microswitch in exactly the right spot as shown below.

The critical bits are:

  • I always fit the microswitch such that the electrical switch contacts are towards the “Right” rail which is always a RED wire on my layout. The centre connection  on the switch goes to the Right rail – clarified further down in the YELLOW BOX
  • the hole in the throw bar must be able to operate the lever on the microswitch (and NOT miss it!)
  • the switch needs to be positioned so that the throw bar will operate the switch (hear it “click”) when the points are thrown.
  • the switch is attached using contact cement (in my case Quick Grip). First work out which surfaces of the point and the microswitch will fit together – they need to be scraped or filed smooth for a good bond. I scrape the underside of the point with a blade and file the bottom side of the microswitch to level it (actually, I hold the microswitch and rub it back and forth on a file).

make sure you don’t get glue into the moving parts and hold it with a clamp as in the photo below.

There won’t be any wires on your switch at this stage.

The two bridging wires here need to be prised out. Check the instructions with new points or on their website.

The easiest way to lever the two short wires is with a small screwdriver.

Then put a small amount of flux on the 4 rails shown. Use something like Carr’s Red Label or DCC Concepts Flux – a non-corrosive type.

The 4 rails have had a spot of solder to “tin” the rails and on the left a piece of tinned copper wire has been soldered in place. You can buy that from electronics suppliers like Jaycar.

The rails on the left are bridged and trimmed; the wires in the middle removed; and attention moves to the frog connection on the right.

The wire provided needs to be extended to reach back to the microswitch. Use similar size tinned copper wire. Here the extra wire has been twisted around the original and will be soldered together first then run down the length of the point.

This diagram explains what is happening electrically. In my method, the switch becomes part of the point to feed the correct polarity from the Common connector on the microswitch to the frog – as shown above by the GREEN connection 3.
On my layout, an additional (Light Blue) wire from the Common connection on the microswitch is taken below the layout to be used to indicate which route is set on the panel. This means my panel LEDS show which track has power.

The extra tinned copper wire has been soldered to the point wire and is run in the least conspicuous path. I gently melt the wire into the underside of the sleeper with the soldering iron to hold it in place.

The wire from the frog terminates at the Common connection on the switch – may be labelled       “C” or “1”

The wire from the frog terminates at the Common connection on the switch – may be labelled           “C” or “1”

This rail area indicated has been tinned ready for connection …

…and this one ready for the other side.

As the run is only a few mm, bare tinned copper wire is fine.

Another view.

These wires run through the foam benchwork and connect to DCC (red & green) and the 3rd light blue wire provides a common connection (from the frog) to allow an indicator to show which way the points are set.

The LH connection is the common pole in the SPDT switch (SPDT= Single Pole Double Throw)
The middle contact connects to the red (Right rail DCC wire) and the RH contact connects to the green  Left rail .

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 switch is off centre. In this case the point was being operated by Wire-In-Tube via the trench shown.

Having marked out the position of the recess for the microswitch, cut the underlay and foam with a sharp knife.

Routing the hole to a depth of 10-12mm with a Dremel (and vacuum cleaner).

Dremel Cutter
Ready for a test fit.

The final steps which can be done after the point is installed:

  • remove the over-centre spring IF you are using servos to control the point – this can be done from the top.
    My points are operated using servo control technology designed by the MERG UK group and built by the user. The points operate at a slow speed and can be set up using a computer interface to smoothly touch the stock rail. See MERG site.
  • leave the spring in place if you are manually switching the point.
  • notice that the sleepers near the mechanism have been thinned down from their over-scale size.
  • if servos are used, the throw bar ends can be cut off.
  • weathering will improve the realism of the installed point.

Joining Rail

“Aligners” for Connecting Rail

Flextrack needs to be connected by “rail joiners”. I prefer to call them “aligners” as they really can’t be relied on to JOIN or at least electrically connect two pieces of track. They do a good job of keeping the ends of the track in-line.

But don’t rely on them for electrical connections!

The photo above shows from the top:

  • a standard Peco “joiner” for Code 75 flex track (which is what I use on my layout).
  • a shortened joiner which aligns the track, but is SHORT enough to be moved along the rail if track adjustment or point removal is needed (trust me , it will be!)
    I have had cause to remove points which were glued to the road bed with latex carpet cement. Brushing some water around the sleepers freed the point after 10 or 15 minutes and then slide the joiners sideways to lift the point out.
  • a small tool consisting of 2 offcuts of rail soldered together so that the smaller joiners can be held on the LH end to trim the ends neatly.
    The tool is also useful to ensure that the ends of the shortened joiner will easily slide on the rails.

SHORTENED JOINERS: to make these:

  • cut the Peco joiner in half with a motor tool (get 2 for the price of 1!)
    to do this I hold the joiner in one end of the jig which is held in a vice.
  • file the ends square – to do this hold it with the shorter end of the little jig in the top photo.
  • scrub the end of the joiner with a wire brush to clean out the end.
Cut the rail to length if necessary. Use something like “Xuron®” cutters as shown below. File the ends of the rail to remove any burrs so that the joiner will slide on easily.
Showing how to cut the rail with a “Xuron®” cutter. The flat side of the cutter should face the rail to be used.
Don’t use these cutters on hard materials like steel wire (and how do I know this?) The last photo in this post shows the right tool to use on hardened wire.
Remove the rail chairs from the last sleeper (tie) with a sharp blade. In this case I am using a surgical scalpel.
A good way to ensure you don’t rip off a sleeper or cut yourself is to use a piece of scrap wood to cut against.
The chair needs to be completely removed so the joiner can clear the sleeper.
The short joiner will slide up the rail and be flush with the end. If you use a full size joiner, it will not slide up far enough to clear the join.
When the track is fixed down, this method allows the rail or point either side of the join to be disconnected by sliding the joiner to the left or right.
To cut hard wire such as “piano” wire use this tool. A beautiful German tool designed for the job. I couldn’t find anything locally and was able to buy it on eBay. Just search for the name showing on the handles.

Track Feeders & Buses


No … not that sort of bus!
In our case it’s a wire, or a collection of wires that carry an electric circuit or a data circuit.

In the underside view of this little demonstration layout, the Bus wires are the RED and WHITE pair which carry the DCC Bus along the bottom.
Tapping into it at several places are DROPPERS or FEEDERS (red and black) to carry the DCC circuit to each piece of track on the top.

In this example the bus is connected to a PCB strip in 4 places to simplify connection of the droppers to the bus.

I will have a post to cover using printed circuit board PCB for various purposes.

 

See: Making Simple PCBs

This an underside view of my layout with 4 bus wires in view.

A = DCC main bus; (heavy duty stranded copper wire) Red = rear track wire
B = 12V; (H/Duty above) Blue is Positive and White is Negative
C = DCC sub bus (in this case from the main bus to the YARD bus). This allows
me to easily isolate that section.
D = MERG Can-bus which distributes the electronic data around the layout.
Note that it is very thin as it carries low current signals.
Note also that the wires carrying a data signal A,C & D are all lightly twisted to lessen interference one to the other.

Note the colour coding – there is no fixed rule but RECORD your code.

Our problem is to get the track feeders through the baseboard, in this case FOAM, to the Bus underneath. EVERY piece of track must be fed between joiners. There is a special issue with foam.

Some sources indicate that the foam can react with the plastic on electrical wiring and cause it to break down. A wooden base board can just be drilled 6mm.

So, after we have drilled the hole in the foam (as shown here with the 6mm K&S brass tube drill still in place) we need to line the hole with an inert material.

 

Note the colour coding – there is no fixed rule but RECORD your code.
See the Post on DRILLING HOLES IN FOAM for more info.

Because this section of my track was using Expanded foam (not recommended) I had to clean the hole out with something that was a loose fit to get rid of all the little white balls of plastic.

This is not needed in Extruded Polystyrene Foam. See details on foam HERE.


The 6mm hole is an exact fit for a drinking straw. My preference is for the paper straws but they seem to have disappeared on the far South Coast so plastic ones will do.

Measure it to be 5 mm longer than the total depth of foam and underlay.

 

 

Coat the straw lightly with some PVA…

 

 

 

 

… and slip it into the hole.

 

 

 

Wipe off the excess PVA …

 

 

 

 

…and do the second one.

 

Now we come to the bit where you need to solder a wire to your track, take it down the feeder hole and connect it to your Bus wiring.
Shown below are the tools you will need for the top side. I have a colour code for the droppers – RED is the Right DCC track (or in my case, the REAR track closest to the wall in an around the walls layout). My front rail is fed with GREEN (because I had heaps of that colour).

In a module you just need to be consistent making sure that no swap-overs occur.
As can be seen at the top, I have a main DCC bus which feeds 4 sections – North (Carriage Works), South (Loco), East (Yard) & West (Station – “Bolgan Road”).

Each section is fed via a STOP LIGHT BULB in series with one feed wire. If there is a SHORT CIRCUIT, the stop light bulb will carry the load and LIGHT UP.
See THIS SITE for more info. Or THIS ONE.

Strip 1cm approx.
The wire I used was from Jaycar and is sold as
Flexible Light Duty Hook Up Wire 13 x 0.12 tinned (WH-3005 green)
Twist the strands tightly together.
A typical appropriate soldering station.
Put a tiny amount of liquid flux on the bottom flange of the rail.
Pick up a tiny amount of solder and tin the bottom flange.
This is a better photo of how the tinned flange should appear.
Use a sharp blade to cut a slit in the track bed to allow the feeder to drop straight down from the rail, as in the last photo.
Tin the end of the feeder wire – ideally only the last 2mm!
This is where the self closing tweezers are handy.
Line up the end of the wire with the flange …
…and try to solder just the tip of the wire to the flange,
Then push the wire down and into the slit made earlier.

If you are working on a timber baseboad, the feeder hole can be drilled between the sleeper (tie) ends under the connection point and there is no need to line the hole.

Once the track is painted (weathered) and ballasted the feeder should be almost invisible. The feeder is shown at the end of the toothpick.

The photo above  shows some of the kit I use when working under the layout.
There is:
1. a low level seat which can slide on the floor
2. a low level 240v light (LED) which has now been replaced by a similar size rechargeable LED work light,
3. soldering station,
4. wire strippers, knife, sidecutters (not visible) for removing the insulation from about 1cm of the Bus wire.
5. and, BEST of all – a locking clamp with a roll of solder attached so that it is easily accessible.    See the post on Strain Relief to help you work under a layout.

This is the LED battery work light. It is a 10W 6000K (cool white) unit which is also useful for colour painting.

 

 

 

Laying Track to Foam

I chose to use foam as the baseboard of my layout. I started experimenting with this in 2008 (Photo). This actual track on the test rig was only pinned in place as it was never permanent.

  • Foam base is great to lay my Peco code 75 HO flextrack. I can easily pin it in place using ordinary dressmaking pins. But you can’t nail it down.
  • Instead, I use an adhesive, LATEX CEMENT and I buy it from carpet suppliers or carpet layers. I take a 1 or 2 litre plastic container and get it filled for say $10 or so.
  • It needs to be thinned with water to a consistency of milk. I originally thought it would need to be thicker, but the thinner it is the better it penetrated under sleepers etc.
  • What happens if you change your mind and want to move something? It is actually reasonably easy just by dissolving the dried latex – see the last photo.
For the track base I use a product from DCCconcepts (in Western Australia) called Trackbed OO/HO Scale 3mm
The company describes the product as:
“A box of 100 feet (31metres) of high quality, OO/HO Scale trackbed (3mm thick / scale 9~10” approx high).
Made from very long life EVA, closed cell foam trackbed with precut ballast shoulders and a pre-scored track centreline underneath to allow it to be easily split for laying along track centre-lines if wanted.
Based on tests and feedback each piece is 605mm / 2 feet long for easy handling. Cuts perfectly with a snap off knife.”
STEP 1 – track pieces were pinned into position according to the layout sketches. The layout plan was derived in a slightly odd way. Firstly I laid out old code 100 track, some points, paper copies of points until things were as I wanted them to be. I then took a whole series of overlapping “aerial photos” as shown above and below.
And subsequently “stitched” all the photos together on a PC so that I had a somewhat bizarre mosaic diagram of the layout:

STEP 2 – the Code 75 Peco flextrack was adjusted into position with dressmakers pins (easy in foam)
Curves were laid out with Masonite (hardboard) templates. In this case 1m radius.
Note the use of plywood alignment pieces to keep the track joins in line.
STEP 3 – once I was convinced I had the track in the right place, guidelines  were needed to allow the underlay to be glued in the correct position.
To do this I made a little mobile jig from an old loco pony truck with a ply guide screwed up from the bottom so it just cleared the rails.
  • This foam roadbed is lightly cut down the centre to make it easier to lay curves.
  • The other advantage of gluing the track to foam is that it provides an improved noise barrier.
  • That is lessened of course when the track is ballasted but I am experimenting with very dilute latex as a ballast adhesive.
STEP 4 – I ran this mobile jig along the pinned track to get a guideline for the edges of the underlay.
STEP 5 – I took no photos of this process, but the diluted latex cement was brushed along between the guidelines onto the foam (none was brushed onto the bottom of the underlay). The underlay was butted up to the end of the previous piece with a little cement brushed onto the end. No weights or clamps were necessary although some pins were used around curves.
The photo above shows the container of diluted latex glued to a block of wood to help prevent spills. The photo actually shows a point being glued to the underlay and weights ARE needed for this process.
STEP 6 – The track is held in position by long dressmaking “T” Pins.
This aligns the track but allows it to be lifted to coat the underlay lightly with latex cement.
STEP 7 – for long runs, I held the track up with paddle pop sticks which allowed me to brush on the cement.
I used a chisel shaped brush about 10mm wide and applied it sparingly down both sides.
As above but a little more latex cement was needed under the PCB sleepers which were later cut across the join. A better solution would have been to use a more powerful adhesive under the PCB sleepers eg. Liquid Nails, as this track needs to be cut and remain strongly fixed.
STEP 8 – Once the glue is in place, remove the paddle pop sticks and place weights on the track until the glue sets.
The long brown strip is paxolin – about 3mm thick and cut to fit precisely between the rails. It serves to align long straight section and can be left in place until the glue sets. It can be made from any similar rigid maerial.
I have many of these 2mm (0.080″) plywood pieces cut to be a neat fit inside the tracks.
They guarantee alignment of track especially with crossovers.
Small pieces are great for keeping curves aligned where flex track joins. In this photo Carr’s Flux has been used to get a good soldered join between rail and sleeper (tie).
Using a long straight edge on the edge of the rail and the paxolin stip between the rails to align trackwork past the future station site.

WHEN THERE IS A DISASTER:

If everything goes pear shaped, then Latex bonded track or points can be lifted. Realising an extra crossover was needed, I had to lift a section of track. Brush some water onto that section and leave it for an hour or so and a thin spatula can be worked under the sleepers to free the track/point. The old latex can be removed with a wet sponge.

Yes, yes … I know if I am flooded out, the trackwork may be in trouble. But the bloke in the house across the road will really be in strife. The peak of his roof is lower than my floor!

Servos for Points

Points /turnouts on my layout were initially operated manually using a wire-in-tube mechanism. There are currently 44 points on the layout and I started converting to servo control about half-way through.

The wire-in-tube (WIT) method I used worked very well and is shown to the right.
The mechanism is relatively easily fabricated and the cover is removable with one screw to allow easy adjustment of the point blades at the fascia.

It will handle a second wire to allow push/pull operation of 2 points in a crossover.
If there is any interest, contact me and I will add a section on the design and fabrication of the WIT method and the fascia mounted lever frames..

I changed to servo operation for the following reasons:

  • with this type of mechanical operation, control panels would not be able to operate the points (there are 4 mini panels on the layout).
  • the system selected allows precision adjustment of each point blade; variable speed of movement; position indication
  • servos can be installed from the top of a 50mm (+) foam layout
  • points can be controlled from a central position; a local panel; by a computer; as a route by changing many points at once and other options.
  • the system I use is based on the UK MERG model. Circuits vary from simple to complex.
  • Plus – I like working with electronics.
The photo shows the basic setup. The servo is located to the side of the point/ turnout and connected to it with a short “L” shaped wire. I use 1.2mm steel wire running through a short guide tube. This connects to the servo arm via a “Quick Connector”. The servo cable exits under the layout. SEE PHOTO
The mounting slot in the foam is formed by drilling 12mm holes through 50mm foam to fit a micro servo … SEE DRILLING HOLES IN FOAM
The guide tube I use is a short piece of bicycle bowden cable outer – used for gear selection from memory. I just bought a metre or so length from the local bike shop.
The servos I use are Tower Pro SG90 style or my preference Micro 9g Metal Gear Servo.
Shown above is a “Micro 9g Metal Gear Servo For Futaba Hitec HS-55 GWS walkera RC HELICOPTER GA” as described on eBay.
Here is a LINK to the eBay site I used but check other sources for a possible better deal. The current cost is $4.87 (16 July 2016) with free postage to Australia. There are cheaper plastic gear models but I have found these ones to work more smoothly and to be much quieter. As you can see, they come with a variety of servo arms (aka servo horns) and any will work in this application.
To connect the servo to the point/ turnout a “Servo Quick Connect” (shown above) is very good. I bought a set of 20 for $4.12 !! ($3.83 in June 2017)
That’s a little over 20c each. They were sold as “Durable 2mm Aircraft Stopper Servo Connectors Connector with Screws – Set of 20” and one eBay supplier I used was at this LINK . These things are TINY. The Allen Key grubscrew is 3mm.
This what you get for about 20c (Aust). A beautiful piece of micro engineering.
I use any of the servo arms supplied. Select the second hole from the pivot point of the servo arm and drill a 2mm hole in there to take the servo quick-connect. The point needs to move less than 3mm (HO) and initially I went for maximum torque by using the first hole and that is what is shown in the very top photo of this post. That hole is too close to the hub of the servo arm and some fiddly trimming was needed. I discovered that there is no need to use it as there is plenty of torque when using the second hole as shown above.
Assembly order is shown for the quick-connect. It needs to be free to rotate in the servo arm and the nut is best secured using a tiny bit of thread locker. The grub screw allows positioning adjustment but the travel and end points need to be set by some electronics.
This servo is being retrofitted to a turnout on EPS foam. As the control wire to operate the point was already in place, an additionally longer access slot was needed to allow the servo to slide in under the actuating (control) wire to the throwbar. The brass foam “drill” can be seen on the right.
Shown above – 2 MERG boards in use on my layout. The left hand one controls the servos (8 of them) and the right hand one handles the switches controlling the servos operating the points. This system was devised by the MERG group in the UK – see their Website MERG.  The operating system uses a CAN bus (2 wires) to distribute control events around the layout in a manner similar to that used in modern motor vehicles. You still need a distribution bus for DCC (plus, in my case, sub buses for the yards etc) and a bus for 12V DC to operate points and the power the CBUS boards.
This is a MERG design for TESTING SERVOS with the left hand one designed only to test servos – in this case I use it to test new servos and to set them to their midpoint.
The right hand one is, in effect, a stand alone method of controlling one servo & its point with a switch. The 3 blue components are variable resistors used to control the speed of the servo and distance it moves Left & Right. I also use it for testing the servos.

MERG sells kits for the above 2 projects and they cost just £1.55ea  +postage from the UK for MERG members. Almost all of the more sophisticated CBUS kits are based on professionally manufactured Printed Circuit Board (PCBs) and usually kits of the necessary parts are available or you can buy the parts locally.

There are other alternatives:

The device shown to the right is a ” MegaPoints Controller” by a UK company and could be very good for those people not confident in building PCBs themselves. I have not used it or seen it in operation but it comes ready to connect to 12 servos and has 12 corresponding switch inputs. Here is their Website and here is a YouTube Demo There are 2 videos in sequence. Cost is said to be £50 in the UK.

I also notice that DCC Concepts have an “above board” system that looks interesting for someone not interested in a DIY approach – Cobalt SS.