Loop

Arrangement looks fine to me.

If you have another loop at the other end of the layout you'll have to do the same thing there. By turning that part of the loop into the reversing section, both mains at the crossover location can be the same polarity.

Reversing? Quite possibly

Jerry,

If the two lower left tracks coming from the east and west ends are ends of a loop, then yes, the crossover turnouts create a second reversing situation.  

I think having a uni-directional staging yard is a great idea.  I have one planned myself.  

Regards,

Dave

Dave, Can I insulate

Dave,

Can I insulate between the two sets of crossovers and then on the left side of the first left hand turnout in the bottom track to isolate the entire loop and the bottom set of turnouts?

Or would I be better off putting in a diamond and make a four turnout crossover and then insulate the diamond?

Thanks for everyone's help.

Jerry

One way to do it

Jerry,

There are many ways to do a reverse loop and here is a drawing of one way to do it.  This was the first solution considered on my own layout.  It requires all four crossover turnouts to throw at the same time, along with a DPDT relay which will reverse the phase of the entire loop.

This method of powering the reverse loop is taken from the concept Charlie showed on the peninsula of the BC&SJ recently.  The two frogs in the center can be powered by a Tam Valley Dual Juicer.

The mainline is a loop on the left side with two tracks leaving the mainline in a sort of a wye.  The reverse loop on the right will have 5 storage tracks. 

Another solution is a double-reverse loop where the staging loop reverses off the short center section of track, which in turn reverses to stay in phase with trains entering/leaving the mainline at the left.  Since I figure that only one train at a time will be entering/leaving I will likely use a much simpler concept by bringing the tracks from the mainline wye into a short single track section then wye out to both ends of the 5-track staging reverse loop.  

The turnouts are actuated by Tortoises which also power the frogs and activate the 4PDT relays.  Two poles of each relay power the track and two poles will reverse the LocoNet RailSync, which will keep it in phase with the track and allow a BDL168 to operate correctly on the staging loop.  The detection in staging is used for automation.

The layout is a folded dogbone with a single track mainline and 3 passing sidings.  With this loop staging added to the mainline a train can leave Salt Lake (staging loop) in the morning traveling to Denver (same staging loop), lay over during the day and in the afternoon travel from Denver the opposite way around the mainline ending in Salt Lake.

And I am certain there are other ways to solve your puzzle.

Regards,

Dave

How to modify your diagram

Jerry,

As I re-read your messages I realized that I had not completely answered your questions.  I took a few minutes with your diagram and have another solution.  As shown in your drawing leave the insulated joiners on the far right end of the loop near Turnout B, but move the lower gap to the left to include Turnout A.  This might work best with an automatic reverser such as the PSX-AR.

Next you need to create a second reversing section as shown in the diagram.  It could be reversed using a DPDT relay when the West turnout is thrown.  A relay would be recommended because of the current draw from the number of planned staging tracks.  The new reverse section would include the remainder of your staging yard as shown in this drawing.

Do you plan on detection in the staging yard?  And if so what system?

Also, I see no problem with having all the trains go the same direction around the staging loop.  I have operated on several layouts that do just that and I plan to do so.

Regards,

Dave

Crossovers

That arrangement above which requires all turnouts to throw simultaneously and changing polarity within the crossover seems unnecessarily complicated compared to simply isolating a train-length section of straight (as in schematically, not connecting back to other sections of track, it could be curved) track in the loop(s) at either end.

Entrance from the West

Jerry,

Is (or can) the track entering from the mainline to the West turnout (lower left) long enough to hold your longest train?  

If so it could be your second reversing section instead of reversing the part of the staging yard with all the tracks, and will make life much simpler.  Let me know and I will revise the drawing.

Regards,

Dave