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TEMPLOT is Martin's hobby project. Everyone is welcome to use it and join in the ongoing developments. Thanks for visiting Templot Club.
COT track is the name for Templot 3D printing where we print the chairs and sleepers/timbers at the same time using FDM (filament) printers, this is ideally suited for 7mm scale and above, you need only 1 printer and rails are threaded on to the track base, the system has been designed to be easy to use.
Like plug track the idea was to make the build process as easy as possible. With the exception of the rail filing jigs, no gauges or special tools are required. Nor do you have to build any complicated subassemblies. You will find the build process slightly different to traditional methods, hopefully very much simpler
The filament we use is PLA+, this is important as we need the chairs to have a bit of elasticity when we thread pre-curved/bent* rails through the chairs
* I am talking about gentle curves and bends (see wing rail fitting method later in the topic)
All rails should be prepared, firstly file off all the burrs after cutting the rails, and square off the ends. Then with files slightly chamfer the foot and webs at both ends, this makes fitting the rails much easier and prevents breaking chairs
I thought I would share one of my builds which is a 31.5 (0MF) gauge A-5 turnout
For now I will bypass turning a 2D template into a 3D printable file, which can be the subject of a separate file and leave filing jigs to another topic. There is a guide to using the filing jigs on this link https://85a.uk/templot/club/index.php?threads/how-to-using-the-templot-rail-filing-jigs.1049/
As can be seen from the template the A5 turnout is 450mm long, the issue in printing my bed is 210mm so I have to print the template in 3 sections (in Templot we call these bricks) I will leave making the print files to a separate topic
Here are the 3 prints, I have found that in 7mm scale brick joining clips are not necessary, as code 125 rail is strong enough to firmly hold all together, others may feel clips are required, simply a personal choice. Templot has a system of printed clip connectors you can use.
The center brick was printed over size then all 3 bricks were trimmed to fit, photo shows 2 timbers discarded
Here we have an A5 turnout base ready for the rails to be fitted. If I created this in traditional method it would have taken me hours to get this far
I start the build first with the heal brick, this is where most of the work happens and as you can see the wing rail jaws are separate from the chairs at the wing rail area. This is to make assembly of the wing rails much easier, whilst preserving the prototypical bend at the knuckle
But before I start explaining the build process, I must describe the common crossing, as it differs from the normal turnout build practice.
Firstly there are the prototype spacer blocks (in the center between the timbers), these ensure the vee and wing rails are held in the correct position
Secondly you will see three of the central common crossing chairs have no outer jaws, the separate jaws have been printed between the timbers instead, this is to aid fitting the wing rails
Using a Vee rail filing jig,(Jigs will be covered in another topic) you file one side only of both Vee rails, this is how the locating chair block is designed to accept the rail. The two Vee rails are prepared this way and simply slide into position. It is important that the rail on the "straight-ahead" side is put in first. Also make sure the rails are the right way up in the jig when you are filing them. They won't fit in the chairs upside down. The thick edge of the rail is at the top.
Once you are happy with the positions you may wish to apply a small spot of superglue to one chair to hold all in position
The rails simply slide into position, you may prefer a spot of superglue to hold the rails securely in position
Wing and check rails can now be formed, tip is not to over bend the rails. Chamfer the rail ends to aid fitting the rail at both ends on the foot and web
Second tip is to make a short rail with a pronounced chamfer at one end, to slide the rail through the chairs to clear out any debris left by the printing process. All rails need preparing by slightly filing the ends of both the feet of the rail and webs, simply to aid threading the rail through the chairs
First up is to gently thread the wing rails through the chairs (from the heal end) one at a time. When bending the wing rails you need to very slightly under bend the rail, so that the wing rail sits against the Vee, too much will break the two whole chairs. If a chair does break, super glue it back.
Next up again gently thread the check rails through the chairs, I have found that if the check rail flares at the ends mirror the plan there is enough give in the jaws, too much flaring is both un-prototypical and could damage the jaws. Again a spot of superglue may be required to hold each rail in position.
It might be better to cut the wing rail chair jaws one at a time, as each one is specific to its position. Trim to fit and glue (2 part epoxy) in place, the holes in the chair bases is for glue to have a better key.
Do each chair jaw in turn (2 stuck in place)
All chairs glued in place
Now prepare the stock rails. The straight stock rail just needs both ends prepared, The curved stock rail needs the set bent in place, then gently curve the center of the stock rail guided by the plan
The set bend is very important, as it allows the switch rail to maintain the gauge
The straight stock rail is simply gently slid in place, I find from the heal is the easiest
Then the curved stock rail is slid into position, but I find this time from the toe end
Next up is to make both switch rails and slide into place
I use the Exactoscale H section functionable plastic fishplates, these both align the rails (if needed) and form an electrical isolation
Second switch rail fitted, now waiting for a temporary tiebar for testing
I also fit electrical bonding wires, across the common crossing (which if left long can be used as a dropper wire) and electrically bond the switch rails to their stock rail.
As you can see how easy it is to build a turnout using the COT track system, no complicated soldered sub assemblies, gauges to test only and no waiting for glue to set or hours of soldering
Best of all is the level of chair detail obtained using this process, ability to alter the geometry in the design process and it does to break the bank in costs
Like plug track the idea was to make the build process as easy as possible. With the exception of the rail filing jigs, no gauges or special tools are required. Nor do you have to build any complicated subassemblies. You will find the build process slightly different to traditional methods, hopefully very much simpler
The filament we use is PLA+, this is important as we need the chairs to have a bit of elasticity when we thread pre-curved/bent* rails through the chairs
* I am talking about gentle curves and bends (see wing rail fitting method later in the topic)
All rails should be prepared, firstly file off all the burrs after cutting the rails, and square off the ends. Then with files slightly chamfer the foot and webs at both ends, this makes fitting the rails much easier and prevents breaking chairs
I thought I would share one of my builds which is a 31.5 (0MF) gauge A-5 turnout
For now I will bypass turning a 2D template into a 3D printable file, which can be the subject of a separate file and leave filing jigs to another topic. There is a guide to using the filing jigs on this link https://85a.uk/templot/club/index.php?threads/how-to-using-the-templot-rail-filing-jigs.1049/
As can be seen from the template the A5 turnout is 450mm long, the issue in printing my bed is 210mm so I have to print the template in 3 sections (in Templot we call these bricks) I will leave making the print files to a separate topic
Here are the 3 prints, I have found that in 7mm scale brick joining clips are not necessary, as code 125 rail is strong enough to firmly hold all together, others may feel clips are required, simply a personal choice. Templot has a system of printed clip connectors you can use.
The center brick was printed over size then all 3 bricks were trimmed to fit, photo shows 2 timbers discarded
Here we have an A5 turnout base ready for the rails to be fitted. If I created this in traditional method it would have taken me hours to get this far
I start the build first with the heal brick, this is where most of the work happens and as you can see the wing rail jaws are separate from the chairs at the wing rail area. This is to make assembly of the wing rails much easier, whilst preserving the prototypical bend at the knuckle
But before I start explaining the build process, I must describe the common crossing, as it differs from the normal turnout build practice.
Firstly there are the prototype spacer blocks (in the center between the timbers), these ensure the vee and wing rails are held in the correct position
Secondly you will see three of the central common crossing chairs have no outer jaws, the separate jaws have been printed between the timbers instead, this is to aid fitting the wing rails
Using a Vee rail filing jig,(Jigs will be covered in another topic) you file one side only of both Vee rails, this is how the locating chair block is designed to accept the rail. The two Vee rails are prepared this way and simply slide into position. It is important that the rail on the "straight-ahead" side is put in first. Also make sure the rails are the right way up in the jig when you are filing them. They won't fit in the chairs upside down. The thick edge of the rail is at the top.
Once you are happy with the positions you may wish to apply a small spot of superglue to one chair to hold all in position
The rails simply slide into position, you may prefer a spot of superglue to hold the rails securely in position
Wing and check rails can now be formed, tip is not to over bend the rails. Chamfer the rail ends to aid fitting the rail at both ends on the foot and web
Second tip is to make a short rail with a pronounced chamfer at one end, to slide the rail through the chairs to clear out any debris left by the printing process. All rails need preparing by slightly filing the ends of both the feet of the rail and webs, simply to aid threading the rail through the chairs
First up is to gently thread the wing rails through the chairs (from the heal end) one at a time. When bending the wing rails you need to very slightly under bend the rail, so that the wing rail sits against the Vee, too much will break the two whole chairs. If a chair does break, super glue it back.
Next up again gently thread the check rails through the chairs, I have found that if the check rail flares at the ends mirror the plan there is enough give in the jaws, too much flaring is both un-prototypical and could damage the jaws. Again a spot of superglue may be required to hold each rail in position.
It might be better to cut the wing rail chair jaws one at a time, as each one is specific to its position. Trim to fit and glue (2 part epoxy) in place, the holes in the chair bases is for glue to have a better key.
Do each chair jaw in turn (2 stuck in place)
All chairs glued in place
Now prepare the stock rails. The straight stock rail just needs both ends prepared, The curved stock rail needs the set bent in place, then gently curve the center of the stock rail guided by the plan
The set bend is very important, as it allows the switch rail to maintain the gauge
The straight stock rail is simply gently slid in place, I find from the heal is the easiest
Then the curved stock rail is slid into position, but I find this time from the toe end
Next up is to make both switch rails and slide into place
I use the Exactoscale H section functionable plastic fishplates, these both align the rails (if needed) and form an electrical isolation
Second switch rail fitted, now waiting for a temporary tiebar for testing
I also fit electrical bonding wires, across the common crossing (which if left long can be used as a dropper wire) and electrically bond the switch rails to their stock rail.
As you can see how easy it is to build a turnout using the COT track system, no complicated soldered sub assemblies, gauges to test only and no waiting for glue to set or hours of soldering
Best of all is the level of chair detail obtained using this process, ability to alter the geometry in the design process and it does to break the bank in costs
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