Very true that plastic chairs on their own can't hold the tricky bits. By that method I really mean not using a) rivets, which I tried on a test piece and hated, plus it nearly drives you insane adding the cosmetic half chairs afterwards, and b) copperclad sleepers, again because of the chairs.
In a turnout there are inevitably small sections that chairs won't suffice for, but these can be pre-assembled onto bits of fret-waste on the bench and then epoxied in place.
Shown here (upside down of course), where the substrate has been added to coincide with sleeper positions.
In a slip the principle is the same, the complicated bits are electrically a unit, so they can be soldered as a unit and then epoxied into place.
I must disagree with you, see #20 I have built both in 00sf and EM gauges turnouts without Common crossings built up as sub-assemblies. The only soldering required is producing the Vees, droppers and bonding wires. I would not use this method when sticking plastic chairs to ply timbers.
The proviso is that you use plastic timbers, for the common crossing for looks you use the Exactoscale E4CH 502A Common crossing chairs, with the exception than in the B chair position on the wing rails you use a cut down Exactoscale E4CH 403A 0.8 mm check chair (for 00 & EM gauges) E4CH 402A (P4) , and at the central part of the knuckle (X chair position) you use the central part of a check chair. Additionally in the A chair position the tip of the vee is held up to the correct height by a sliver of 20 thou plasticard
Here are a few photos of a P4 turnout (forgot I built one using this method in P4), I have also built to EM and 00sf gauges using this method. The turnout base I am using is one of the Exactoscale plastic turnout bases which is fine for both P4 & EM gauges. For 00 gauge you will have to use timbers from the Exactoscale Point and Crossing pack E4XX PCT0
Here I have soldered a piece of 0.5 mm copperclad to the tip of the Vee, plasticard packing works just as well
Standard chairs have been added to the Vee, the copperclad has been trimmed back flush with the rail
First wing rail fabricated, standard chairs at the toe end, a modified check chair at the flared end (outside of one chair cut off leaving the spacer
The Vee is fitted first, followed by the straight stock rail, then the wing rail can be fitted
Second stock rail fitted along with the second wing rail
First switch rail fabricated waiting to be fitted
In conclusion the chairs hold the rail in place without any problems, just have to take a little time in adjusting the bends in the rail, and allow the solvent to set before removing the gauges.
Here is a link to the Exactoscale Common crossing chair position sheet which will show chair positions
Edited by hayfield, 16 December 2017 - 10:06 .