GE TTI NG R ID OF SO ME OF THO SE AWF UL GAPS

Brian Harrap

Now that you have taken the plunge and are fully committed to the idea of P87 modelling, (congratulations), and are contemplating building your own P87 turnouts and crossings, it may be time to pause a little and muse over how working to super-finescale standards can be turned to advantage in a way you may not have considered before.

The method you may choose to construct your trackwork is of little concern here.  The thing that has been bothering me most since moving into Pscale modelling (can someone please come up with a better expression than that?) is how some of the neccessary electrical gaps for two rail operation intrude upon the appearance of the otherwise good looking track that Pscale allows us to create.  The smaller the scale the more the gaps seem to offend.  Of course the gaps needed for normal section breaks and for expansion will always be with us.  Please make them as neat as possible and give some thought as to their location from an aesthetic as well as practical point of view.  I'm sure you're doing that already.

I have for some time now, when building turnouts with pivoted blades, been using the mechanical gap of the pivot as the electrical gap for isolating the live frog

Figure 2: The flangeway gaps at the obtuse angle of a crossing also serve to electrically isolate the frogs.


Figure 1: Points are attached to pivots at their ends.  The resulting mechanical gap also serves to electrically isolate the crossing V.

(crossing) from the stock rails and making the wing and closure rails all as one piece.  Maybe not 100% to prototype but it is another ugly oversize gap got rid of.  Put in a scale cosmetic one if you wish. 

I have been happy enough with that solution but the gap required by closure rails of diamond type crossings still bugged me.  I have been building quite a bit of street trackage lately and this particular insulation gap was really showing up badly.  Again I used a mechanical gap to do the job of an electrical gap as well.  The mechanical gap of course is that between the end of the closure rail at the K (obtuse) crossing.  This only works with Pscale construction of course, as properly assembled, it is impossible for the back of the wheel to touch the end of the now all in one closure/wing rail and cause a short circuit.  If your chosen prototype calls for a guard rail adjacent to the K crossing then the gap is even more disguised.  Watch this space for a report on further developments I am working on in this area.

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