Terry Bendall wrote:
Digest sheet 23.6.3 available at https://www.scalefour.org/members/digests/#23
or for those who have it, on the CD given to you when you joined includes notes on building curved turnouts, including a Y turnout. (Halfway down page 4, LH column.)
As described, that creates an ordinary single-sided turnout with contraflexure. The switch deflection is on one side only. To produce such a template in Templot takes about 2 seconds simply to set the curving radius negative in a standard turnout. That's the correct type of turnout to use on the inside of a curved crossover, as suggested there, and generally in running lines.
But it's not a Y-turnout in the normal sense, which requires a switch deflection on both sides, with the angle halved each way (or sometimes other than a 50-50 split). Such turnouts are quite rare on the prototype, and normally found only in yards and sidings. If used in a running line they require a speed restriction over both
routes, and are found only on specially constructed long main-line junctions.
Although there is no specific function in Templot to create a split-deflection switch, it is quite easy to improvise one as shown in that old video clip. I get asked about that so often that I'm going to add a tools > make
function in the next program update to improvise such a Y-turnout automatically.
Alternatively, a proper prototypical Y-turnout can be built up from partial templates by experienced Templot users.
For years I have been intending to do a complete re-write of the template generator engine to permit splitting of the switch deflection, but it would be a major task and I fear it is now too late. But the open-source version of Templot is available for anyone who wants to have a go at it.