SP Jawbone Branch (Part 56) - Rough Foam Scenery for Owenyo#3 (Sept 14)

This blog post might just like the plains of pink foam without much happening... but there will be some basic changes and sculpting of the foam going on.

SP 3203 mocked-up working the trestle spur with some GS gondolas.

This is where I'm really starting to focus the construction of the layout module to match or at least capture the look of the prototype, compressed into my 48" radius 90 degree curved corner.

September 14, 2024

So I took most of a week away from the construction, allowing the layout construction and gluing to cure well.  Construction resumed at about 7pm on the 14th.  I put in more foam between the mainline roadbed and the spur pit roadbed.

Gluing down the roadbed.

In this photo, I'm applying the weight of the water-bottle to help keep the Gorilla Glue from swelling up, and lifting the foam in unexpected ways.  The yellow cheese-grader looking "Sur-Form" tool is handy for trimming down the foam and shaping it as well.  I used it to rough in some details over near the ballast deck bridge, and also shape down some of the foam form a bit during the course of the night.

The larger foam sections are installed, but at this point I'm gluing in the smaller sections and pieces of foam to complete a good solid surface.

At this point I'm cutting the 45 degree chamfers along the pit-track.

The many little scraps from cutting up the foam sheet provided plenty of pieces to stuff in all the little holes.  Several square or rectangular pieces were cut at roughly a 45 degree slope, to then glue in along the square edges of the foam and spur pit edges.

Checking a low-angle view with the trestle.

Again, the main concern with the trestle pit track is how far below the "natural" ground level it should be.  The main measuring point for this is the height of SP 1948/49 GS Gondolas and the trestle's bents.

At this point I dropped the trestle mock-up 3d print in place.

The main track really cuts across this view of the trestle, showing how much of the mound of dirt between the main track and the tighter radius spur's curve has been compressed.

More of a side-view of the trestle.

It's hard to get the camera's point of view low enough to replicate the "standing" view of a person walking around on the natural ground level, yet still see the details of the terrain.  About this point, I was coming to the conclusion that I would have to continue the climbing slope up to the backdrop, which will match the prototype.  In real life, nothing is flat, nothing is smooth... you might think it's flat, but it could be the whole field or area of the terrain is actually on a 2-3% grade.  I believe that's what subconsciously is going on in Owenyo.  It should be able to blend into the backdrop as the erosion terrain blends into the Owens Mountain Range to the east.

Here's a side view with a GS gondola.

I want the foam to be roughly at the bottom of the side-sheets of a standard GS gondola.  The foam surface will be a bit below what the final scenery level will be, once I add the Sculpt-a-Mold and dirt to the top.

A bit of wetted MDF roadbed from gluing in the last sections of foam.

This last section of foam was a trick to put in, as it has to transition from on top of the spur's roadbed near the trestle, to under it near the switch.  This resulted in some openings in the foam, and I filled those with some Gorilla Glue soaked paper-towel.  Effectively "Gorilla Glue Hard-shell", for those familiar with standard plaster 'hard-shell' scenery.  As this module will be movable, I don't want to have anything at this level of the structure being standard plaster, which I've all too often seen come unattached from the layout structure and sub-roadbed.  I want this glue-joint between the foam and the MDF structure to be very secure.

Nearly the end-view that I'll have if you eye-ball the scene with the door module out.

The white "snow" in the background is actually more paper-towel "Gorilla hard shell." stuffed into a few other cracks, along with some of the expanded Gorilla Glue foam, which will be Sur-Formed down later.

Checking how it looks with four GS gondolas spotted.

The last section of bents on the trestle don't have any dump chutes, so the standard gauge cars have to be shoved about half a car length under the trestle to be filled to the end of the car.  It's about 2-car lengths to the overhead tell-tales.  Often the photos of the real trestle show 4-5 cars spotted on the spur, which would basically be a second full spot of the trestle.  Thankfully I've been able to work in the spur to be able to hold the four cars at the trestle and another four "off-spot" on the spur between the last dump chute of the trestle and the fouling point of the spur switch.  Actually I've planned it now so the total of 8 cars on the spur will clear the lift-out section across the door.  I don't want to disturb the spotted cars in the spur to open or close the door. 

Higher view of the spur in place.

Sadly, there will only be room for four GS gondolas instead of the prototype's five cars.  It won't really matter in the operations of the trestle-dump.  It may mean that the trains will be a couple cars shorter, however there's some thoughts that have come up discussing the multiple different ores and minerals that were loaded here.  

Overview of the whole module with the 4 GS gondolas and trestle mock-up.

I'm starting to think the reason there's often photos of more cars than can fit, is that they were swapping out which standard gauge cars were loading what into them.  If dolomite was being loaded, then they needed the dolomite GS cars, if they're loading something else, then they'd need those SG cars.  Also added into this the fact that the smaller ~20-ton Narrow Gauge cars would take several carloads to fill a standard gauge GS gondola.

This is my plan around the end of the spur

Eventually there'll be a timber retaining-abutment wall at the end of the spur, where the trestle transitions to the ramp sections.  I set this in with a single small piece of foam, then back-filled it with another larger scrap.

Higher view of the spur and main track with the 45 degree pit foam in place.

Off-level curve in the foreground is starting to be marked in red.

By this point I'd sanded down the roadbed and taken the warp out of it.  Then I came back and re-marked the 48" radius centerline for the main track.

September 15, 2024

Midnight came and went... The planning and work on the module continues.

Overview of the whole corner of the layout.

There's still plenty to do to get this module finished.  Several times during this construction, I took the module off from the wall brackets and pin/bolts to the #2 Module, allowing me to see how heavy the structure is.  Now that it has foam glued in, the whole module is very rigid, yet quite light.  I need to get a bathroom scale out sometime and weigh it.

Another overview of the whole module.

There's obviously still track-work to apply, drill and solder on feeders, and then run all the under-module bus-wiring to install.  The staging yard will also require a string of LED lights along the front frame to light the yard.

A view at the door with the two roadbeds and foam cut off even at the end of the module.

I'll still need to drill and mount the alignment pins and bolts for the section across the door, but for now the end of the module is looking good.  The foam scenery is roughed in as well, with a nice subtle taper down to the inside of the spur switch.

In Closing

This brings us to the point where I had to stop construction and focus on the preparation for the Southern Pacific Historical & Technical Society 2024 Convention in Sparks, NV.  There will still be more carving of the foam on this module.  I'll probably be doing more direct photo comparison against the photos I've collected of this area around the trestle.  The foam beyond the trestle spur, probably will be on a slightly steeper slope, and I may work in a section of the SP Narrow Gauge mainline.  I've also marked out a couple of radii options for the curved backdrop that will be built in the corner.  I'm considering as tight as 12" Radius and as high as 18-24".  I'll probably work on a card-stock sheet mock-up of the options, take some photos, and see what works.

Staging how SP 3203 will look switching the trestle spur.

The next big step before I should get the track layed in place will be construction of the bridge section across the door, and I'll need to actually start building the Bartlett module to provide the opposite end of the bridge section.  The spur's switch will be on the door section.

Side Note: The Code 70 ME track I ordered arrived.  This will be to replace all the main-line track.  So around this time, I removed the spikes holding down the main track on Owenyo #1 & 2 Modules, disconnected the bus-wire feeders and disassembled the west wye switch (which is on the main track).  These 3-4 sections of Code 55 flex track will be swapped out with the new Code 70 track.  I still need to get the new Code 70 Points and Frogs made, but hopefully by the end of the year that can happen too.

The west end of Owenyo's siding switches are also a point of decision which I'm still pondering.  I need to look at it carefully to decide exactly where I'll be building the two switches in relation to the Owenyo #3 Module's curve and spiral easement.

Jason Hill

Related Articles:

Jawbone Branch Layout Build Index - All articles in the construction of the Jawbone Branch layout.

SP Jawbone Branch (Part 55) - Installing Spur and Foam Scenery for Owenyo#3 - Previous blog post

SP Jawbone Branch (Part 54) - Roadbed & Rough Scenery Foam - 2nd oldest blog post on this module.