Winter Project - Test track

Thinking through what I need to do to build the 57xx chassis I suddenly realised I don't have anything to test the chassis on. My test track would have been ideal if it had not been relegated to the garage (and is currently in pieces). Earlier in the year I was treated to a Bachrus rolling road and I've found this very useful in testing some of my RTR locos, though, I don't think it gives a true picture of how a loco will travel along the track. Or is this just because I like to see the locos move....?

Anyway a random length of redundant wooden shelving was retrieved from the dark recesses of the said garage (I knew it would come in useful one day), and thoughts were put towards what I might require on this strip of wood for testing locos.

1) A length of straight OO track for setting up the Bachrus rolling road and testing RTR locos prior to conversion.
2) A length of straight P4 track for setting up the Bachrus rolling road and testing locos after conversion (also for testing any chassis I manage to build during their construction).

3) A length of P4 track with a reverse curve to test a loco's abilities to travel through a minimum radius curve.

Item three above is the tricky one as what is the minimum radius curve for P4? Or possibly more importantly, what is the minimum curve for any locos I may be building? Templot shows alarm warnings at 39.4" yet the P4 Society seems to recommend not going below 48" for large locos. I guess it must come down to the length of a loco's wheelbase as to the minimum radius curve the loco can travel through. The shorter the wheelbase the tighter the curve. For the time being I cannot see myself building anything much larger than the wheel base of a WR Pannier tank. Beyond that perhaps, if my skills will allow, a 4-6-0 'N' Class and a Manor, both of which have driving wheel wheelbases similar to a Pannier tank. So I've plumped for the 39.4" radius curve as a minimum.

It's a bit rough and I will put some ends on to stop flying locos but for the moment it's located on my bench with a wall at one end and crocodile clips at the other. It may not be the most suitable test track but for now I think it should suffice.