To answer the original question about PCB ties, in case anyone is thinking of trying it, here is how I do it:
I recommend making 1 in 5 ties PCB on straight track, 1 in 4 on large curves and you might need 1 in 3 on tight curves. Roughen the underside of the PCB ties with sandpaper and glue down with your favourite contact cement.
Rail should be pre-curved to lie at least approximately along the desired radius, in order to increase accuracy of gauging when laying the rail, and also reduce the sideways force on soldered joints when finished.
Pre-tin the entire underside of your rail - I use a silver-bearing solder that melts at 179 degrees C, which is strong and flows easily so it doesn't build up all thick and blobby. The brand I use (Carr's from C+L Finescale in the UK) doesn't have a flux core so I use Carr's Yellow Label flux applied with a small artist's brush. This is not as much a chore as you might think, because the solder only goes where you put the flux, so a bit of care with applying flux helps keep everything tidy.
Pre-tin the area of the PCB ties where the rails will be located. Position a rail where you want it, hold it down with a wooden stick, dab on a little more flux, then I like to touch my pencil-tip soldering iron to top of tie while pressing it against side of rail at the same time so that both get heated. The joint goes 'Phhht!', you take away the heat while still holding the rail down for a couple of seconds, and then it should be there to stay.
It pays to check alignment of rails very carefully and repeatedly as you go, because it's not as easy to adjust a rail later - the many soldered joints prevent the rails from sliding along, which also prevents you from pushing a rail sideways very far....sounds like experience talking, doesn't it?!
Once in desperation I got rid of a kink in a rail by putting a narrow cut in the rail in the middle of the kink. The ends came together as I pushed them sideways to correct the kink.
Bear in mind that PCB doesn't like being heated too much, or else the copper surface can peel off the resin laminate. Believe it or not, the trick is to use a fairly hot iron and get in and out QUICK. This seems counter-intuitive, but even a low-powered iron will eventually cause the copper to peel off.
If your iron doesn't have enough boogey to heat the rail-tie joint up to the melting point of your solder FAST, then the rail, which is an excellent conductor of heat, is sucking all the heat out of your iron and you end up holding the iron there for so long that everything gets hot and unhappy - ties, nearby soldered joints, fingers, tempers.
I have tried holding the tip of the iron on the top of the rail, but I found this heated the rail too much either side of the joint I was trying to make and sometimes got solder on the railhead which made more work, cleaning it off - far better to press down with a wood stick (which doesn't absorb heat) and heat the rail right at the point you're trying to make the joint.
I use several track gauges either side of where I am soldering, to make sure the second rail is properly in gauge. I make my own 3-point gauges with three pairs of cheese-head screws drilled and tapped into pieces of whatever plate is laying around at the time. The pairs of tapered screw-heads will slip easily onto the rails and then hold them snugly, assuming you have calculated the spacings correctly.
Having said all that, after expending a lot of effort painting PCB ties to look like wood, I am spiking the rail to pre-stained wood ties for my latest project so that they look a bit more uniform for less effort, with a PCB tie only either side of layout joins. Can't say how successful this will be - I haven't got very far, got a small dose of open-heart surgery (I know, I know, that's like saying 'slightly dead' or 'barely pregnant') four weeks ago which put the brakes on everything.
Well, I'm sure I've probably left something out, so feel free to fire away with any questions.