Tehachapi, BC

[jagged ben]

...An alternative which might be preferable is two reversing sections: one in leg C-C'' of the wye (which is longer than the longest train) and one in the single track section between Woodford and Walong, which is 16' long (just barely longer than the longest train).  Given the complications of the C''-C''' relay solution, this may be the simplest way to go.  Comments welcome.

If the Woodford to Walong single track section can be one signaled block then I think that makes a lot of sense for a reversing section.  You just don't want a following train to cross into the section if it might have a yellow.

As for the other reversing section that would be needed, why not just make it the Storage Yard as Brandon suggests?  You are surely not going to have two trains passing through the turnout at C at the same time. 

[GaryHinshaw]

If the Woodford to Walong single track section can be one signaled block then I think that makes a lot of sense for a reversing section.  You just don't want a following train to cross into the section if it might have a yellow.

Exactly.  Per my signal plan from several pages ago, there is tentatively an intermediate signal within this block at MP 350.7.  I would have to deal with that.  Two other factors: 1) this stretch is just 16', and my grain train with DPUs can be hovering right around that length, 2) the wiring in the upper deck and in the section A-A' is already wired with colour-coded polarity per the above schematic.  I would have to relabel some of the main line wiring.  I think I still prefer having the C''-C''' section be the reverser, despite the complication of the one-to-three split.

As for the other reversing section that would be needed, why not just make it the Storage Yard as Brandon suggests?  You are surely not going to have two trains passing through the turnout at C at the same time.

Yep - that would work fine.  Thanks as always for the feedback.

[daedal_arcanum]

First off, welcome to Railwire Brandon -- and thank you for a thought-provoking first post!

Thanks Gary!

and a blow-up of the wye section it contains:

Thaks for the updated schematic.  One question: neither this nor the previous schematic show a connection at the far (from staging; i.e. far-right) ends of the upper and lower levels, but that is in the plan, isn't it? 

Given this duality, a reversing section from C''-C''' is the simplest because it can serve both as the tail of the wye, and as the main line reversing section.  It would be really simple if the single track portion of C''-C''' were long enough to hold a complete train, but alas it is not, hence I must include a portion of the 3-track section of the Mojave staging helix.  This introduces a complication: if a train is crossing one end of the reverser at C'', I have to be careful to avoid having trains simultaneously crossing at C''' if all 3 tracks are under the reverser.  The current plan is to use relays to route only the lined track through the reverser, so trains in the other two tracks can cross C''' without restriction.  This is a tricky bit of wiring though, and I haven't fully come to grips with it yet...

I understand now what you are trying to achieve here, and i think the relay contacts of the tortoises could be utilized here.  I will try and draw up a schematic if i have a chance today.

Regards,
--Brandon--

[GaryHinshaw]

One question: neither this nor the previous schematic show a connection at the far (from staging; i.e. far-right) ends of the upper and lower levels, but that is in the plan, isn't it? 

Yes, absolutely.  In this version of the schematic, the blue track does not yet exist.  Eventually north staging will be removed, the lower deck mainline section will be built, and the mainline loop will be closed.  Until then, the reversing section in question only needs to serve the tail of the wye on the left side of the schematic. 

I understand now what you are trying to achieve here, and i think the relay contacts of the tortoises could be utilized here.  I will try and draw up a schematic if i have a chance today.

I would appreciate any ideas folks have for implementing this.  I'm not at all convinced that I have the best solution.  In fact, please see the last paragraph below for a non-switched solution.

As a preamble, I have been finalizing the track arrangement in the helix and I've drawn up a bunch of roadbed parts that I have now sent out for CNC cutting on baltic birch plywood.  (I'm going with 1/4" high-density ply for maximum finger clearance in this section.)  In principle I still have some flexibility in crossover placement in the helix.  Here is my current thinking (this is a blow-up of the orange segment in the above schematic):



Each coloured segment represents a 14.5' train (95% of all trains will be shorter than this): blue trains are originating NB trains headed to Summit, red are terminating SB trains.  Each red tick mark indicates one turn of the helix (the turns are numbered) and in theory I could have a crossover at any tick mark or any half tick mark (the straight sections in the oval helix).  Nominally, originating NB trains would be dispatched in sequential order, but the crossover configuration shown above is intended to give me some flexibility.  For example, I could dispatch the second blue train around the first, or if turn 2 were empty, I could dispatch either of the lead trains in the 3-track section.  As a session progresses, the middle track could be used for terminating trains instead of originating ones, and as time permits, the terminal manager will "flush" the terminating tracks by sending trains back to the storage yard.  I'm hoping this is a sufficiently fluid arrangement...

To get back to the reversing section, I was originally thinking I would make it run from C''-C''', but as I stare at this, it's clearly possible to park trains across the gap at C''', so I should probably lengthen it to encompass the entire 3-track section up to, but not including the turnouts between turns 3 and 2.  This would make it easy to ensure that staged trains are not parked on a reversing gap.  In fact, I'm even wondering if I should just make all the track in turns 5,4,3 permanently under the reverser instead of switching them.  The reason that might make sense is that trains crossing the gap at C'' will be rare: either a transfer job to the storage yard, run by the terminal manager, or a continuous run via Bakersfield.  There is no scenario where a guest operator will run a train through C''.  So it might make sense to simply impose a rule that no two trains cross C'' and C''' at the same time.  Done.

Comments?  It would really simplify the wiring, and I'm a bit leery of actively switching power between fixed and reversible busses underneath potentially moving trains.

-gfh

[jagged ben]

... So it might make sense to simply impose a rule that no two trains cross C'' and C''' at the same time.  Done.

Comments?  It would really simplify the wiring...

How about you go with that plan for now, and if following the rule turns out to be too difficult then you can implement the relay solution later?  (At which point I could draw you a relay diagram as I promised way back when.    )

The only planning ahead required is that you should double-gap the three tracks at both ends now in case it would be difficult to do so later.

I'm a bit leery of actively switching power between fixed and reversible busses underneath potentially moving trains.

I really don't think that will be a problem.  No worse than switching polarity under a moving train, as a reversing section is designed to do.

[Car17]

I know this is a dumb question but, is this N scale or Ho scale? I assume it is N but, the photos for ballasting look amazing and im amazed at how he got such fine detail out of the photo.

[GaryHinshaw]

Thanks for the affirmation car17, it is indeed N.  But if you knew how long I spent ballasting each foot of track (and I have a lot of track now...) you needn't be impressed. The ony secret I have is patience.  I got your PM and will send you some more comments about the steps I take.  I do love a well-manicured heavey-duty mainline!



Despite my lack of updates recently, I have been working my butt off on the Vortex and have now scheduled my first beta session on TBC/2.0 for Jun 13, and have a goal of hosting ops sessions for a regional event this September.  More soon!

[davefoxx]

Gary,

There is not much, if anything at all, in this photo that gives away that the modeling is in N scale.  Fantastic work!

DFF

[ednadolski]

Just curious, Gary, how many (approx.)  feet of ballasted mainline have you completed so far?   And which ballast is that in the pic (Smith & Sons?  Scenic Express?)

Ed

[Cajonpassfan]

Gary,

There is not much, if anything at all, in this photo that gives away that the modeling is in N scale.  Fantastic work!

DFF

+1 here. Wow!
Otto K.

[GaryHinshaw]

Just curious, Gary, how many (approx.)  feet of ballasted mainline have you completed so far?   And which ballast is that in the pic (Smith & Sons?  Scenic Express?)

Ed

Hi Ed.  The ballast in the shot is Smith & Sons Penn-Ohio Limestone, #50.  I'm down to my last half-quart -- plus a pound of nearly matching limestone that just arrived from suesscaboose - yea!  I was curious about the stats myself, so here is a summary of where things stand:

Mainline laid to date: 213'
Mainline still to lay: 90'
Mainline ballasted to date: 133'
Mainline still to ballast: 170'
Pandrol clips painted to date: 31,920 
Pandrol clips still to paint: 40,800
Hours spent painting & ballasting track to date: 399
Hours required to complete painting & ballasting track: 510
Quarts of Penn-Ohio Limestone still needed: 2

[ednadolski]

Pandrol clips painted to date: 31,920 
Pandrol clips still to paint: 40,800
Hours spent painting & ballasting track to date: 399
Hours required to complete painting & ballasting track: 510

 

Well, I guess it still beats hand-spiking....  just don't ever change eras to pre-1997!


Ed

[Santa Fe Guy]

Stunning work on the ballast and painting. Love it.
Rod.

[jagged ben]

Gary,

There is not much, if anything at all, in this photo that gives away that the modeling is in N scale.  Fantastic work!

DFF

Yeah, usually an oversize coupler is the giveaway, but he obfuscated that.   Rail height is the best remaining clue.

[ednadolski]

Gary are you doing anything to remove any of the factory weathering from the railheads?  In that photo it looks to me like it's pretty much all there.  So do the locos all run OK electrically (and traction-wise) even with the weathering in place?


Ed