Steve Johnson Modelmaker
The idea for a French layout came about for a number of reasons. Firstly of course, I find French railways fascinating. They are quite different to ours and wonderfully quirky. As such, I have collected various models of French rolling stock over the years, but with nowhere to run them. I could also do with a test track comprising of a bit more than a yard of flexible track! Points and curves are necessary to test rolling stock properly. However, the only space available was for a terminus to fiddle yard 'shelf' layout.
There are always a number of requirements to be met for any new layout project, so these are some of the criteria for mine. It has to be an SNCF period layout, as that is what all the stock is. Although not really region specific, I do rather like the 1,500V dc motive power, so that places it on the PLM (Paris, Lyon Medetarainee)/Midi areas. It also has to have overhead catenary, not only for the French electrics, but also to test my British electrics. Some of the stock is quite old, but still serviceable, from manufacturers such as the old Jouef, Fleischmann and Roco. This stock has the rather coarse wheel standards of old and would be difficult to re-wheel, so that means using Code 100 track. If you saw the eye watering prices of modern French models, excellent as they are, you would understand why I'm sticking with these for the time being! It will be DCC though. This will make wiring easier (?) and also develop my skills with DCC operation and JMRI as well as using up a box load of Lenz accessory decoders etc. That leads me onto the final consideration. This is not my 'main' layout and I don't want to throw money at it, but rather one that will be constructed on a tight budget. It still has to look and perform well though.
As the foundation of any layout, good solid lightweight baseboards are very important. I bought mine from Grainger & Hodder as kits. They are laser cut 6mm ply and are easily and quickly assembled by a tab and slot system using PVA wood glue and small tacks. Having assembled the boards, they were treated with a couple of coats of varnish. Grainger & Hodder also supply brass pattern makers dowels and latches to enable the boards to be accurately aligned and joined together. Cork sheet was glued to the top of the baseboards ready for tracklaying.
Trackwork is always a problem for me, mainly because non of it looks realistic apart from hand built track. However, this is a HO scale layout, not OO. That means that most of the commercially available track is suitable, sort of. Availability is another consideration which lead me to using Peco Code 100 track. It has its problems, but can be made to look reasonable and work well with some modification. After a bit of weathering it shouldn't look too bad. As I already mentioned, I will use Code 100 on this layout to maintain compatibility with my older stock. The points will be of the 'Electrofrog' type to improve running qualities.
As this is primarily a DCC layout, there are no electrical track sections as such. A power bus consisting of 1.5mm2 twin and earth domestic lighting cable runs from end to end under each baseboard. Droppers are taken from each section of track and soldered to the power bus. This includes multiple sections of track on what appears to be one continuous line joined by fishplates. The reason for this is that the fishplate is not a reliable electrical connector, especially when using potentially high currents associated with DCC. A high resistance joint between rail and fishplate could cause the joint to heat up to the point where it starts to melt the plastic sleeper base.
Peco points are described as 'DCC Friendly', but there issues with this. They can be used 'out of the box' with DCC. However, the main problem for me is that the switch blades change polarity as the point is changed. This means that the stock rail and adjacent switch blade will be different polarities. If the rolling stock wheels happen to to touch both of these rails, there will be a short. Most DCC power units will immediately cut the power upon the detection of short, hopefully minimising any damage, as there could be up to 10 amps flowing through the short! You are still left with the locomotive stuttering or stopping though.
Another issue is that the switch blades rely of physically touching the stock rail to make an electrical connection. This can be a bit hit and miss at times, especially as the points age, tarnish, pit or bits of detritus, such as ballast granules, getting inbetween the rails.
Fortunately, with a little work, these problems can be overcome. It is strange though that Peco have not yet bothered to modify the trackwork, despite DCC being around for some time now. The first thing to do is to break the bonds between each switch rail and crossing vee. The switch blades now have to be bonded to the adjacent stock rails. This way, both rails are the same polarity, so no short could occur. The switch blade is no longer reliant on physical contact for electrical continuity, but is hard wired. These measures will improve running tremendously and incidentally, are worth doing on an analogue layout! It must be pointed out though, that any modification, such as this, invalidates the guarantee!
I have used the Peco PL-10 point solenoids on PL-12 mounting plates fitted underneath the baseboards. However, due to reliability problems experienced with Peco's polarity switches in the past, I have used separate microswitches, sourced off eBay, for crossing vee polarity switching. The power feeds for the microswitch are taken off the power bus whilst the supplied attached wire on the point is used for the switch output. Another microswitch provides positional feedback for the Lenz/JMRI system, but more of that later. These two microswitches are actuated off the operating bar on the PL-12 mounting plate which has been modified to have a 'T' bar at the end.