Tehachapi Loop II

[ednadolski]

Time for  a quick update. I've completed the base for the next section of the layout:



This is for the part of the layout that I call the "West Curve" which lies between Woodford Siding and Tunnel 9.  Here is what it looks like with the subroadbed temporarily placed in position atop some 2" WS risers. Final installation with the 2% inclines will come later, after all the base sections are put together.




Here is an in-progress pic with all the clamps still in place while the glue is drying:



Whoever said you can never have too many clamps sure was right.  This is every clamp I own that would fit, and it was just enough to do the job.

Only 6 more sections to go.  This work has to be done out in the garage because of the Liquid Nails construction adhesives that I am using.  I need to finish them all before it starts getting too cold to work.

Ed

[GaryHinshaw]

Custom benchwork is cool!  What are we looking at here in terms of materials?  Are you laminating two thin plys for the outer beam? 

Will the layout remain fully modular, with standalone legs for each section, and connector-ized wiring?

[ednadolski]

What are we looking at here in terms of materials?  Are you laminating two thin plys for the outer beam? 

It's mostly baltic birch plywood: 1/4" for the top surface and stiffener plates; 1/2" for the subroadbed, and 3/4" for the end plates and the cross-beams. The latter need to be heavier since they are used (a) for bolting to adjacent modules; and (b) to anchor the vertical supports for the backdrop.

For the curved sections I am using 1/8" poplar bending plywood, which is very flexible and can bend to much tighter radii than I have on this module.  On the back side I laminated two layers together to help make it stiffer.  The other side will also have a second layer laminated on top of it, which will also serve as the fascia.  I'm planning to add that later, after the track goes in.

The baltic birch is substantially pricier compared to the stuff from the big-box store, but is way worth it since the quality is so much higher:  more plies, better stability, and fewer voids & weak spots.  I got it from a local lumber place that also rippped the bending ply to the 3 3/4" wide strips that I needed (fortunately for me, since the bending ply is so flexible it would be hard for me to cut on my small portable table saw).

Will the layout remain fully modular, with standalone legs for each section, and connector-ized wiring?

Some sections will have standalone legs, but for the four main loop sections it's more efficient to make some kind of L-girder frame that will support them all.  The Woodford section will attach to a wall and sit on some kind of shelf brackets.   My main goal is to build the layout so that it can be moved to a new space if/when the need arises, but it is not intended to be genuinely portable in the sense that it can be loaded onto a truck and taken to train shows and events.  (I could probably convert it to that if I ever wanted to.)

Not all sections will sit at the same height, so I expect to make some adapter plates to make up for the vertical differences where needed.   I'll use birch table pins to align the sections and 1/4" hex bolts with fender washers to hold them together.

For now I am thinking of perhaps terminal block wiring between sections, but it could well turn out that connectors are cost-effective and would work just as well in the long run.

So far I am pretty pleased with this approach.   The modules are rigid and relatively light weight.  If desired, one could further shave weight by reducing the amount of 3/4" plywood and by cutting out 2 1/2" circles in the framework members with a hole saw (think aircraft frames).   And while I would not recommend walking or sitting on them, the modules are plenty strong enough for supporting the weight of track/trains/scenery.  One limitation is that it might not be easy to make significant changes to the track plan, but that is not a factor in my case.

Cheers,
Ed

[C855B]

... cutting out 2 1/2" circles in the framework members with a hole saw (think aircraft frames). ...

I did this with a N-Trak module frame a few years back. Familiar with the technique not just from airframe engineering, drilling was common practice for bicycle racing in the pre-super-alloys days. With the module, I was somewhat surprised how little it actually saved - at best, 5% of the total weight. Plus by the time I was done, I had burnt - yes, literally - burnt through four hole saws. Plywood resins are heck on saw teeth.

[ednadolski]

I've completed the seven remaining module sections and moved them indoors from the garage.  They are now stacked up and waiting to be assembled and installed (eventually -- I still have to build the framing that they will sit on):



(Kind of looks like an oversized jigsaw puzzle.)


I've also started on installing the suspended ceiling in the train room:



I'm using the 'Genesis' tiles which are made out of PVC rather than than the regular acoustic tiles. The Genesis tiles do not routinely shed dust (and actually can be installed in clean rooms and food prep areas).  Should go a long way to keeping the layout cleaner and minimizing maintenance.

Once the old layout goes out, I'll be able to finish the ceiling and start installing the new lighting.

Ed

[ednadolski]

I've been looking over some recent videos showing trains on the Loop running on the new section of double-track:

This has got me thinking about updating my layout plan to the current era with the new track in place, and trying to think of the various trade-offs:

- The construction changes would not be difficult. I would have to modify one of the sections that I have already built, and the control panel would change.  There would be one less turnout/CP to build, and the curved staging turnout that I pre-built would have to be modified.

- The new cut presents a scenic difficulty, in that it opens up a reveal to the staging area behind the backdrop.  So far I have not hit upon a solution other than to just push that part of the backdrop a bit further back, and build some additional scenery thru the cut area.   However that does not seem like enough to adequately hide the hole from normal viewing.

- I'm trying to figure out the impact on operations.  It appears from the videos that the 'typical' prototype pattern is simply to run southbound trains on main one (thru Tunnel 10)  and northbound trains on the new main two.  Trains stop either at Walong or Woodford to let opposing traffic on the single track main pass.   So the operational focus would change from managing meets on the shorter (old) Walong with trains of varying lengths, to managing the bi-directional traffic on the Woodford-Walong single track.  I'm wondering if that might be a bit too simplistic as an operating scenario to keep a layout interesting to run, even for a single person.

At this point I'm running about 50/50 on going in this direction.   What are everyone else's thoughts?  Are there any constraints or difficulties or benefits that I have overlooked?

Thanks,
Ed

[jagged ben]

Noooooooooo, don't do it!   

I'm just prejudicial against the BNSF 'swoosh' paint scheme. I would model the earlier era.  That's my only real reasoning.   Plus it seems to me that you laid out several points against the change, and none really in favor. 

[Smike]

First off if those videos do not want to make someone model the loop, I don't know that anything will.  I think if you extent the backdrop far enough back (more than 12") then I think the only way you are going to see the hole is from looking straight down.  I think it would add to the scene in seeing a bit more track prior to going into staging.

So if I understand it correctly the change would only effect trains moving south. (At least visible trains) In the original plan SB trains might need to hold on the Walong siding until tunnel 10 clears. Trains moving NB would be unchanged as they still would need to hold in Walong.   Also instead of more or less having one train hold and one passing on the entire  on-stage part of the layout, you now have a section of the layout which will have 2 trains moving on the same section at the same time.  Railfanning 2 opposing trains on the same track is a plus in my opinion. (Just as shown in the first video) You can also now have 2 NB trains coming out of staging with one holding in Walong (unsure if that is feasible in reality on line)

Really love this plan either way.

[ednadolski]

Noooooooooo, don't do it!   

I feel your pain.   I am a bit nostalgic for the way things were in the searchlight era, when I first visited the Loop in-person.   Life was simpler in those days. 

I'm just prejudicial against the BNSF 'swoosh' paint scheme. I would model the earlier era.  That's my only real reasoning.   Plus it seems to me that you laid out several points against the change, and none really in favor.

A first I had not been particularly overwhelmed with the 'swoosh', but over time I've become used to it.  I expect to have some of those in any case.

On the 'pro' side, it is the notion of keeping updated and forward-looking that I find appealing.  I also like the idea that I could visit the real Loop or look at new dronefoaming Youtubes and see the real-life version of what I am modeling.

Modeling any contemporary railroad will always be a moving target, whereas a specific era is more like a snapshot.  Hopefully it will be a while before UP decides to fully remove Tunnel 10.  The backdrop hole that would make will be quite a bit larger than the one I am fretting over now. 

I think if you extent the backdrop far enough back (more than 12") then I think the only way you are going to see the hole is from looking straight down.  I think it would add to the scene in seeing a bit more track prior to going into staging.

Here is a drawing to see what it looks like 'on paper', based on the Google maps image:



This superimposes the new track and section/roadbed outlines (in pink) over the existing plan (outlines in blue & black).  This does present some angles where at least part of the hole can be seen, tho at least it is off to the back & side.  It would work better if I could continue the mainline curves thru the tunnel/cut area, but they have to meet up with the (construction currently under way) helix track. 

... you now have a section of the layout which will have 2 trains moving on the same section at the same time.  Railfanning 2 opposing trains on the same track is a plus in my opinion. (Just as shown in the first video)

A long time ago (before I built my first Loop) I was curious about what it would look like to build a double-tracked Loop, but thought that it would be too much of a departure from the prototype.  Now that the real world has changed, that look has become prototypical.

IIRC there is a club layout (Belmont Shores?) that has the whole Loop double-tracked, including the Tunnel 9 area.   I suppose the prototype will eventually conform, altho it may be a (very) long time. 

Ed

[GaryHinshaw]

I can't think of any factor that you're not considering.  In terms of operations, I don't really see that much to choose between the two options unless you intend to run many trains that exceed the length of the original Walong siding.  Do you?

That said, let me propose a somewhat radical option: do both!   Since your construction is modular, it seems entirely feasible that you could design the sections to accommodate it.  If you make your control panel in software, you could pretty easily switch back and forth between control schemes too.  You could take it a step further and have two sets of signals that you swap out as well.  How cool would that be?     I'm just spitballing here, but I would be very tempted if I were planning a similar style of pike.

-gfh

P.S. Thanks for posting those drone videos.  I'm starting to put landforms on my Loop shelf and they have been invaluable for making out features that are very hard to discern from the typical photo angles.  Amazingly, the stills from those videos are as good as any web photos.

[ednadolski]

I don't really see that much to choose between the two options unless you intend to run many trains that exceed the length of the original Walong siding.  Do you?

Most of my trains will (eventually) be 80 cars which scales to a 5000 foot train on the prototype and would be too long for Walong.  A 'short' train of 60 cars should fit on Walong, and this was something I had included in the plan to allow for meets there.  The prototype does on occasion run shorter trains, which likely will continue even in the era of "Walonger".

That said, let me propose a somewhat radical option: do both!   Since your construction is modular, it seems entirely feasible that you could design the sections to accommodate it.  If you make your control panel in software, you could pretty easily switch back and forth between control schemes too.  You could take it a step further and have two sets of signals that you swap out as well.  How cool would that be?     I'm just spitballing here, but I would be very tempted if I were planning a similar style of pike.

Interesting thought, are you proposing in essence to build two versions of the Tunnel 10 section and swap them out on occasion?  It does sound doable, tho the sections are not all that small (like 20 square feet) and it would mean replicating Tunnel 10 and the adjacent scenery.  The upper staging helix turnouts would also have to be built for each scheme, since in the original plan there were three sequential (curved) turnouts (which I have already built at the bench).  The Walonger scheme would have two staging turnouts and they would be arranged differently, so that part would also have to be built so they could be swapped.

I've put a little more time into updating the proposed new section, here is the drawing:



In this drawing the original section footprint is shown as the blue outline.  I was able to reduce the 'hole effect' and still fit the space by making the scene deeper, and also by using a decreasing curve radius on the main2 track thru the cut.  I also have the cut narrowing as it goes further back (a forced perspective trick).    You can also see where the East Walong switch was removed, and the two new staging helix turnouts that take the place of the three turnouts on the original plan.

At this point I am still thinking this thru.  Once I put the modules into place I should have a better idea of exactly how this will all fit into the space, or if I will need to make changes.  I will also look into building a mockup.


In other news, I've gone ahead and disassembled my little Loop layout. Here it is, standing up against a wall in the layout room:




It is a little bit of a sad sight, but I had no choice if I ever wanted to continue working on the new layout.  Next steps are to complete the drop ceiling and install some of the overhead lighting.  Then I can set up the Woodford section, which will go onto the wall where the old layout is leaning in the pic.

Cheers,
Ed

[GaryHinshaw]

Most of my trains will (eventually) be 80 cars which scales to a 5000 foot train on the prototype and would be too long for Walong.

Generally, having more single track is more challenging for operations and therefore more interesting.  But if most of your trains will exceed the length of Walong, then the siding has no real operational value unless you want to get into double saw-by meets, which would be very un-prototypical (but really fun!).  So with the single track plan and long trains, you can only dispatch one train from staging at a time.  With the double track plan, you do at least get to manage the single track below Tunnel 9 and have two trains out at a time.  That said, I think it would be a mistake to think that either plan will hold operational interest for very long.  But given your focus on exquisite prototypical modelling, I think that is fine.

Interesting thought, are you proposing in essence to build two versions of the Tunnel 10 section and swap them out on occasion?

Exactly.  I too was concerned that the upper staging throat would have to be swapped out as well, but now that I see your new sketch, it occurs to me that you could probably insert a LH crossover just inside the hidden section.  That arrangement could accommodate either visible module, although you'd have a short, unused stub when the single track module was in place.  I think it could be made to work very nicely.

-gfh

[ednadolski]

With the old layout now moved to its new place, I have started a major cleanup operation in the layout room.  I have also started laying out the module sections on the floor to see how well they fit into the space:






The Woodford module will install onto the wall with brackets, and I will be building some benchwork to support the remaining sections.

Ed

[Scottl]

Nice painted backdrops- you have a great eye for realistic color and form.  Are they practice efforts (they look identical)?

[ednadolski]

Are they practice efforts (they look identical)?

Yes, and I sure need it.  I'm finding it hard to judge the color as I paint, since acrylics dry a shade darker than when they go on.  I also need to get better at trees.

Ed