There are pretty much three options:Surovi wrote:Can I use point without motor and just leave it unattended?
1. Control the switch manually -- you eliminated this option since you want to leave it unattended
2. Motorize the switch and have the train control it -- this is completely automated as dileTTante described in earlier in this thread. Wiring is a bit tricky but, If done right, it works very well.
3. Have a spring-loaded switch -- this is mechanical automation: the switch is always held in one position by the spring, directing the train into the loop. When exiting, the train approaches the switch trailing the points and the wheel flanges force the points away from from stock rail allowing the train to pass the switch. This is prototypical, btw, some railways use these at unattended passing loops.
Option 3 can be tricky to set up and maintain: the spring has to be strong enough to hold the points tight, lest the train derails when enters the loop facing the points, but not too strong, allowing the flanges to cut the points open when approaching from the trailing end. If the spring is too strong the wheels of lighter cars will jump over the points rather than splitting them.
If you need more details about any of these options let me know.