Looks very intriguing Paul, I don’t know what sleeper size you are working on but here is an extract from a list originally compiled by Brandon Evans for the 7mm NGA handbook.

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Which shows a length of either 4ft or 4ft 6in and a width generally between 9 & 10in.

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Someone mentioned turnout bases and while that sounds like a good idea, I don’t think I would have the skill to shape the parts and fit them without breaking off some of the clips.? However, it might be possible to print the sleepers and baseplates with holes to take spikes, as per the Roy C Link design now produced by KB Scale?

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I am in complete ignorance of 3d cad so I don’t know how easy it would be to provide a range of turnout bases?

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I realise that it is very premature to even talk about turnout bases but I think their availability would increase sales of the track base and a little bit of forethought at this point (pun intended) might shape how you progress with the project.

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Cheers,

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Robin