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Building Pointwork

DocRef: JC12a

For methods of switching pointwork go to Pointwork Control : Overview

The two common types of trackwork systems employed in Gauge 3 are code 250 bullhead rail, with either plastic or timber sleepers, or code 330 flatbottom rail with plastic sleepers.

The code 250 rail is available from Cliff Barker in both brass and stainless steel, together with plastic moulded sleepers and kits to produce turnouts. Turnouts and slip pointwork can also be purchased ready made or as individual components to produce your own "custom" pointwork.

The code 330 brass rail is supplied by Tenmille and moulded plastic sleepers are sold by Garden Railway Specialists, who also sell made-to-order turnouts with timber sleepers. If you wish to build your own code 330 turnouts using plastic sleepers to match the plain track, you can download a file describing the method from this link.

If you are contemplating building your own pointwork, then you may consider using Templot, which is a free piece of software, to design and print out the template, especially useful if you wish to build a turnout to fit a particular situation; a 3-way, a tandem turnout, a diamond crossing, or single/double slips.

There are alternative methods of constructing Cliff Barker pointwork, either using crossings and switch rails fabricated from plain rail or employing Cliff's castings for the crossing and switch rails. If using the plain rail method, then filing and assembly jigs for crossings and the blades are available from The Gauge 3 Society, which simplify the task and ensure accuracy.

Supplier Links:

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The Method of Constructing Pointwork using Cliff Barker's Castings for Crossing and Switch Rails is described below by "Cabbage".

Plans for point work are sold by Cliff Barker and Locomotive Design Co.

Cliff Barker sells plans for; 1.5m, 3.0m, 4.5m and 6.0m radius points.

Locomotive Design sell plans for; 12 feet and 18 feet radius points.

One of the hardest problems of home made points is the "crossing" (often referred to as a "Frog"). The modern method of points making is to use the flanges of the wheels to run on the filled in gaps between the frog and the wing rails. In this way the wheel is supported throughout its motion through the point. This method can, however, produce problems where stock which has coarser wheels than the modern specifications are run, since the deeper flanges cause stock to "jump" when hitting the infill. The start of the Frog point should be at the intersection of the two lines. This is easily found by bending a steel rule and drawing along it. The angle of the Frog depends on the intersection of the two lines. The Gauge 3 Society sells crossing filing and assembly jigs in various angles to ensure correct alignment. It is possible to calculate the angle required based on the radius of the curve -but most people use the table below. Blade filing jigs are also sold by The Gauge 3 Society but, as with the crossing jigs, these only accept code 250 rail and are not suitable if you are using code 330 rail, as supplied by Tenmille and used by Garden Railway Specialists in their track products.

MetresFeetFrog AngleSineCotangent
263.750.25773
2.25740.24283.996
2.584.250.22904.258
2.7594.50.2174.499
3104.750.2064.752
3.251150.1965.005
4125.50.1795.508
4.251560.16426.008
4.5176.50.15216.497

Actual Build.

This is a build of the Cliff Barker 4.5m radius point. All of my points bar two are of this type. I will admit that the first set of points that I built took me three days to do, the last set took me three hours to do.

This is collection of kits that you need to perform this task.

You will see the collection of plastic sleepers and the plastic chairs of various types, the brass casting that forms the switch rails, which I recommend for beginners, and the points lever which is also a brass casting and of course The Plans!

Sellotape the plans together -some scissor work may be required to make all the edges flush. Cover the plans with "Squire Seal". This serves as a protective layer and strengthens the plans. Tape the plans to the edge of a piece of 2x4 foot chip board. Now you are ready to begin construction. De-flash all the sleepers and chairs, then start from one end. Using a set square, position each one normal to the edge of the chipboard. You may find that you have to file the spacer pieces to make this so!

Remove the now squared off sleeper and drill through the nail holes on the reverse side with a 1mm drill. Return the sleeper to the board and then NAIL the sleeper to the board through the plans. At the end of this you should have 28 parallel long sleepers.

The points lever is supplied as one brass casting and you will have to saw the parts off the "sprue" to obtain them as parts.

The points blade rails have a V shaped sprue at the pivot end which just snaps off with a pair of pliers.

The holes have been drilled out to metric sizes rather than BA, in this case M2 and M3 for the blades pivot. The "linkage" between the points lever and the tiebar is made from 3mm electrical loop connectors and a length of brass rod -all soft soldered together. Short lengths of copper tube act as bearing pieces.

This is the nearly completed points kit just prior to the long sleepers being trimmed to size. The wing rails have yet to bent outwards with pliers and the frog is still gritty with flux from being silver soldered together. The frog to wing rails gap will be filled with Milliput to present a flat surface with and on and off ramp at the start and end of the frog.


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Page last modified on February 28, 2018, at 12:19 PM