Reverse loops

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CFRiad
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Location: Vancouver, Canada

Re: Reverse loops

Post by CFRiad »

Surovi wrote:Can I use point without motor and just leave it unattended?
There are pretty much three options:
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.

Surovi
Posts: 64
Joined: Fri Nov 03, 2017 9:21 am

Re: Reverse loops

Post by Surovi »

Thanks both!

All is clear.
I`ll consider options.

Surovi
Posts: 64
Joined: Fri Nov 03, 2017 9:21 am

Re: Reverse loops

Post by Surovi »

Well...another one :)
Does polarity changes on the main track between two loops?
I would like to connect one circle with loop to loop railroad.

Surovi
Posts: 64
Joined: Fri Nov 03, 2017 9:21 am

Re: Reverse loops

Post by Surovi »

Thanks!
I thought so.

Is there a way to engage the train from the other track (closed circuit) to Loop to loop track?

Surovi
Posts: 64
Joined: Fri Nov 03, 2017 9:21 am

Re: Reverse loops

Post by Surovi »

Thanks!

It`s complicated....yes....hmmm

Surovi
Posts: 64
Joined: Fri Nov 03, 2017 9:21 am

Re: Reverse loops

Post by Surovi »

Does this apply to digital too?
Some people say DCC does not have these problems.

This is the track plan:
Image

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CFRiad
Posts: 660
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Location: Vancouver, Canada

Re: Reverse loops

Post by CFRiad »

Hi Surovi,

Don't get discouraged as it is simpler than it seems. Doing it with DCC is actually even simpler than with DC. Here is what you need for a setup that drives your layout as shown in the plan (awesome idea for a layout, by the way) using DCC: To make everything work you need to do two things:

1. Implement the polarity reversing system.
For this you need to insert insulating joiners on both rails at both ends of the loop, right after the turnout. Wire the auto-reversing modules according to the diagram below and you are done.
dcc_revloop.png
2. Implement turnout control
Install two train-activated contacts in each loop, set back from the turnouts, giving the turnout motor time to move the points completely before the train gets to them. The wiring will depend on the type of turnout motor. If it helps you, I can sketch a wiring diagram for the MP motors.

And now the limitations:
  • The length of the trains through the loops is limited by the distance between the train- activated control switches.
  • The speed of the trains is limited by the time the turnout needs to completely switch over from the moment the first wheel activates the switch.
  • The directions the trains travel thought the loop will alternate: first time the train enters the loop the turnout will be, say, in through position and will exit with the turnout in diverging position. The next train entering will find the turnout in diverging position and will exit in through position. If this limitation bothers you, it can be eliminated, but my intention was to keep things simple.
If you do it this way, you will have completely automated reversing loops. They will work over and over, without operator intervention.

Surovi
Posts: 64
Joined: Fri Nov 03, 2017 9:21 am

Re: Reverse loops

Post by Surovi »

Thanks both!
:thumbup:
CFRaid, I`ll ask you for help at the end of March :grin:

Surovi
Posts: 64
Joined: Fri Nov 03, 2017 9:21 am

Re: Reverse loops

Post by Surovi »

Thanks!
:thumbup:

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