Tuesday, March 30, 2021

SP Jawbone Branch (Part 20) - NG Pit Transfer Track at Owenyo

Just a quick update from SP Jawbone Branch (Part 16), where I was working on the NG's "Pit" track at Owenyo.  I'm quickly moving towards the point of laying track... However, I best get any more cutting on the main structure of the modules done before I start putting down the flex track which will catch on the foot of a sabersaw as it runs around notching the top skin of the modules.

Owneyo-SP-401-Returned-from-Bakersfield-195X-Brandon-Collection - Used with permission

Andrew Brandon sent me a photo from his collection which is really cool showing SPNG 401 being unloaded after rebuilding at Bakersfield's Carpentry Shop.  The F-50-series flatcar has a tare date showing 1945, so this is before 1949 at the latest.

Cropped version of the same photo... 195X-Brandon-Collection

In the background of the photo it shows the NG's "Pit" and the profile of how the grade starts compared to the small dirt road crossing both the NG and the SG tracks.  Notice at the NG mainline switch the diverging route almost immediately starts to drop as it rounds down into the pit.

The cuts have been lengthened.

Unfortunately the rear frame rail of the module, which is already been constructed, prevents me from continuing this grade change to the point shown in the photo.  Also there's a good amount of selective compression going on as well... so this is about as much as can be done.

Scenery will fill the opened areas.

This pit drops down deep enough, I'll fill the area with foam and sculpt it to look like the excavated dirt of the prototype.  On the prototype as the SG climbs and the NG draws closer an inclined timber retaining wall holds the ramp back.

In Closing

Here's the finished slotting and cutting work done on the NG "Pit" with the edges cut back.

The next question with the compression will be if I can start to ramp up the standard gauge at the very end of the modeled portion of the layout.  I'm not sure that I should start the ramp up on the modeled area, as most of the photos seem to show at least one engine length of flat track before the ramp started.  This will probably end up being another casualty of the forced selective compression which is imposed by the length of the room.

Jason Hill

Related Articles:

SP "Jawbone" Branch Index Page - Links to all my blog posts on my new Jawbone Branch layout.

Monday, March 29, 2021

SP Jawbone Branch (Part 19) - Owenyo #1 Secondary Bracing & Wye

The last three (SP Jawbone Branch Part 16, Part 17, & Part 18) blog posts have been on the structural aspects of the modules.  Now I'm moving on to the next phase of construction as I wrap up the last of the secondary bracing.

Plan for the underside of Owenyo #1 module

One of the advantages of drawing the structural details on my CAD models is that for several months I've already been visualizing what the structure will look like.

Secondary Diagonal Bracing

Special cut corner 2x2 blocks to accept the secondary diagonal bracing.

Following the same style of diagonal bracing from the Owenyo #2 module and the two staging modules of Mojave Yard, the more complicated Owenyo #1 module mixes diagonal bracing into the heavier support structure for the removable wye.

West end of Owenyo #1 module with diagonal bracing and front edge fascia dry fitted.

The west end of the module is mostly just needing the diagonal bracing installed.  Corner supports for the two diagonals along the front edge are still needed.

East end of Owenyo #1 module with the two "Pits" cookie-cuttered and bent down.

The edges of the Narrow Gauge "Pit" are cut longer and also relieved back, which will have the foam glued in from the bottom to create the slopes.

Finishing the Primary Wye Supports

Wye Issues?

Wye structural support "Keel" or spar.

Without the diagonal truss bracing the module was able to twist when I put a little force down on the tail of the wye spar/keel.  However with the secondary bracing installed the module does not twist anymore.  When force is applied to the top of the wye now tries to lift the whole rear edge of the Owenyo #1 module.  I'll probably still make a bracket or clip to hold the back edge down near the center focal point of the wye bracing.

Sistering & Supporting Front Frame & Wye "Keel"

The last two major structural support elements need to be installed before I can start working on the wye or moving forward with the rest of the construction.

I sistered up the front frame with 2x2s to provide a good anchor point for the lower plate.

This is the rather nightmarish structure to support the removable wye module as a cantilever.

Intermediate 3/4" plywood shims for the support of the wye and front frame.

A layer of 3/4" Plywood is needed to build up the depth to match the oak wye 'keel'.  The two triangles were also thinned to make a shelf, matching the two heavy diagonal frames.

Here's the intermediate cover plate marked to be cut.

I cut the two triangular sections to anchor to the front plate of the wye.  My table saw makes short work of this joint work.  The 2x2 riser cutout is made with a saber saw.

I cut a slot in the intermediate cover plate.

I don't want to cut any more height off the wye's structural keel than I need to.  I cut away two plies of the 3/4" plate.  The right side I also cut away the profile of the 2x2 riser.

The wye tail thinned to match the intermediate cover plate slot.

The cover plate is also 3/4" plywood with the same 2x2 notch cut for the riser.  The intermediate plate layer is glued in place.  

Lower cover plate.

I marked out the four support areas under the plate where I will attach it with screws.  Before I screwed this cover plate in place, I decided that a couple of holes should be added to lighten the module and also to provide some good handles!

Here's the wye 'keel spar' in place along with the 2x2 riser.

The front edge of the layout is definitely heavier now with all this box structure assembled.  Time to test it and see if my balance issue is still a problem.

The cover plate screwed in place with the keel-spar in place as well.

Well, with the module in place it definitely takes very little down-force on the tail of the wye to lift the back edge of the module across the 2x2 riser.  Time to build a bracket to hold it down back there!

Wall Bracket Hold-Down

A couple of scraps thrown together to make a bracket.

I decided the quickest and easiest way to build a bracket for the back of the Owenyo #1 module was to take a chunk of 3/4" ply and a small scrap of 1/4" MDF frame material rem, glue them together.  Then glue and clamp to the back of the module's frame.  (Yes, I'll have to grind off the tips of those two screws, OUCH!)

Hold-down bracket installed.

The module is now secured to the wall and can't rock if an engine heads out onto the wye.  I'll just have to remember to remove these two screws in the wall-bracket when I want to take this module down to work on.  Not a big deal really.

In Closing

Jawbone Branch coming together.

The next step is getting the holes drilled for the alignment pins and bolts.  Then track?  Hope so!

Jason Hill

Related Articles:

SP "Jawbone" Branch Index Page - Links to all my blog posts on my new Jawbone Branch layout.

Wednesday, March 24, 2021

SP Jawbone Branch (Part 18) - Owenyo Wye Construction & ME Track Arrives!

Continuing my layout construction blog posts from Part 16 and Part 17, I'm working on the Owenyo Wye support structure and the start of the wye tail.

The new Owenyo Wye "Keel" mocked-up in place.

Also a quick update: The Supply Train arrived with the order of ME flex track and other bits to start track laying!

The Wye "Keel"

A carpenter friend of mine gave me a great piece of oak flooring, which is hardwood, to make the spar or "keel" of the removable Owenyo wye from.  It has tongue and groove from its original planned use as a strip of flooring.  I ripped off the tongue with my table saw to get a good square edge, which will become the top surface of the keel.  This will mate against the underside of the Owenyo #1 module's 1/4" MDF top skin.

Tongue & Groove of the oak flooring piece.

Notched to fit the rear frame of Owenyo #1 module.

I notched the end of the keel, which will go into the pocket I cut in the bulked up area of the Owenyo #1 rear frame rail to only 1.75" high with my Razor Saw (modeling hand saw).  The fit is rather tight, so I used a mill file to chamfer the edges of the keel and slightly narrow it below 3/4" thick.

Mocked-up with a clamp holding the "Keel" in place under the top-skin of Owenyo #1 module.

One of my small clamps at the front edge of the Owenyo #1 module holds the front of the keel, while the rear point is secure in the pocket.  The balance point of the wye tail will be out away from the Owenyo #1 section. 

An underside view of the "Keel" fitted into the hole in the heavy sister block of the rear frame.

The Keel will be fully cantilevered, and will be actually pushing UP on the rear part of the #1 module's top skin!  At the front frame rail, I'll be making a heavier plate to connect the rail around where the keel penetrates the structure.  

Installing Front Plate & Prep for Wye Keel

1/2" MDF sheet marked to cut the front plat

The mating plates for the wye module are made from 1/2" MDF, 20" long, 3" high.  I cut a notch 2-1/16" high, 3/4" wide for the Keel to slide through. 

Front Plate and Wye Joint Plate notched for the "Keel", notice the angled end of this plate to fit the heavy diagonal braces.

The ends of the front plate for Owenyo #1 is chamfered to match the two heavy diagonal braces I installed in Part 16.  The mating, Wye-side of the joint, is also cut at the same time, which should allow them both to fit very closely together.

Front Plate of 1/2" MDF clamped and gluing with Gorilla Glue.

At the front edge of the wye, 23" from the rear of the module, the new front mating plate with the rest of the wye section.  This plate is notched for the oak keel to slide through, the bottom of the notch becomes the pivot point for the keel, pressing down here and up inside the wye at the rear frame.

The new Owenyo Wye "Keel" mocked-up in place.

I'm testing if an engine is too much weight on the wye tail for the structure of Owenyo #1 to hold down in balance across the front frame rail and 2x2 risers.  I may need to add a screw or catch to keep the Owenyo module from twisting as weight is applied to the end of the wye.  I can also to some extent put a diagonal brace from the wall bracket up to support the front edge of the Owenyo module from sagging.  However, supporting the front edge will not prevent the rear edge from being lifted off the wall bracket there.

Blocks & Bracing

The western bracing blocks are roughed-in to support the heavy diagonals and form the basic truss to suit.

As I work out the rest of the center supports for the Wye Keel, I'll be adding additional plates and blocks in that area.  The areas west and east of the center section still need the diagonal trussing which I've been installing on the "simple" modules before this.  On Owenyo #1 module, I'm wanting to get a firm grasp of what the unique structure will need, so I don't put one of the simple truss pieces in the way!

The eastern end of Owenyo #1 with blocks roughly placed.

Another view of the center area with the riser support which rests on the wall bracket.

I am planning to put a large trapezoidal plate (10x10, narrowing to centered 2" at the rear frame against the top skin) and another heavier plywood 3/4" plate to join the front frame rail and support the Keel.  This front frame under-support will need to be notched to fit the 2x2 riser.  I plan to have the riser fit into a hole in the under-support, so I have that riser over with the Owenyo #1 module to remind me of this plan.

The Wye Tail Construction Contemplation

Here's the rough fit test of the Keel and the wye's mating plate.

While I've test fitted the two main structural parts for the wye, I don't want to permanently glue them together yet, as I still need to do some modifications to the Keel for the additional 1/4" MDF sister under the center area of the wye.

The Supply Train Arrives!

Pile of Code 55 flex track, a bundle of Code 55 Rail, and a single pack of HOn3 Code 40 for the scenic NG along the backdrop.

The ME track order just arrived today. Hopefully the DTW switch parts will be arriving soon, which will allow me to start construction above the top skin sheets.

Additional ME materials: Rail Joiners (Code 55 & 40) plus two bags of spikes.

I decided to get extra ME spikes.  I have some remaining from my old bag from years at LMRC, but rather have plenty.  I needed to get smaller rail joiners.  My LMRC stock was only Code 70 for what I've been working on at the club.

2x2 corner block material

I also went out this week to pick up a couple more 2x2s to make more corner support blocks for the diagonal truss installations, which should be upcoming.  These will be cut into smaller pieces to anchor the diagonal truss and make risers from.

In Closing

Just for fun Mojave Staging with some 36" long sections of Code 55 ME flex track roughly placed.  Yes, I'll straighten them before fixing in place!

So, with the arrival of the ME flex track, I can start laying the staging yard tracks in Mojave.  Before I can really fix the flex track down, I'll need to do all the alignment and bolting holes in the modules to keep them in proper position.  Also, I'll be start with the switch ties, followed by flex track in Owenyo soon.  Having an engine running may happen soon!  All of which will be covered in upcoming blogs soon!

Jason Hill

Related Articles:

SP "Jawbone" Branch Index Page - Links to all my blog posts on my new Jawbone Branch layout.

Thursday, March 18, 2021

SP Jawbone Branch (Part 17) - Upgrading Bracing, Mojave Structure & Foam

This post is a quick follow-up to SP Jawbone Branch (Part 16) which mostly covered the more complex Owenyo #1 structure and the brackets used to hold up the south side of the layout.  I realized that I haven't really posted photos of the upgraded basic structural system within the modules themselves.

Owenyo #2 with bracing removed

My first implementation of the bracing under the standard modules was with mitered and glued joints, which several of my friends who I consult with expressed concerns about.  After I've built the stronger version of this structure used on Mojave West and Middle panels with 2x2 corner blocks which were cut to accept the braces showed a much better strength, I planned to knock out any braces that were not firmly attached on Owenyo #2 panel and upgrade the installation.

New 2x2 corner blocks cut and slotted for installation.

I used the table saw with additional 3/4" ply shim to move the 2x2 blocks being cut to the proper location over the angled blade.  Definitely use the plastic push handle to guide the lower part of the block through the saw.  I was very carefully holding the upper corner of the block, but sure that I was not pushing into the blade if the block kicked out of the saw.  I want to keep all 8 fingers and 2 thumbs for many more years!

The other main change I made with this upgrade, which I planned to do before I actually glued them, was to thin the braces to only 1" from the edge thickness of 1.75".  

The new braces are all test fitted before glue is applied.  A small hammer is used with a scrap piece of MDF preventing damage to the edge of the MDF braces.  Clamps are used to hold the 2x2 blocks in place while the glue dries.

Cutout for the foam scenery insert in Owenyo #2.

The thinned diagonal braces are shown here.  I broke the edges of the MDF with a rasp.  Many future cuts will be prevented by doing this.

Here's the "tunnel view" of the Mojave Staging Yard with Owenyo #2 module above.

In the above photo, notice the reduced height of the bracing.  This is the upgrade which I planned so that my knuckles don't get killed reaching into the staging yard!  The stack distance at the front edge is only 4", but it's now 4.75" to 5.75" in the interior space above the staging yard.  I know the track will raise the equipment a few fractions of an inch, but the new space should more than make up for that.

Middle Mojave Staging

The last of the plain panels to build is the "Mid-Mojave" panel.

Diagonal EF and FG installed with new square braces at E and F on Mid-Mojave

The blocks are marked A, B, C, etc to show where on the panel they go.  The diagonal braces are also marked AB, BC, etc to show where they go, as each is cut to fit.

Mid Mojave panel with diagonal braces prepped.

I used some of the wider strips to make the bracing under Mojave, as it will not be needing the same type of tight access.

Large Clamps used on the five square cross braces at the west end of the Mid-Mojave panel

This one used Tight-Bond II wood glue and was quickly assembled with the large clamps spanning over the square braces and the smaller clamps holding the 2x2 blocks in place while the glue sets.

Middle of the panel clamped and glued.

At some of the corner blocks I have added pieces of 1/4" MDF to fill the slots or wedge the braces to exact length.

Eastern end of the Mid-Mojave panel

I may decide to add a couple of support blocks where the black marks are on the front and rear frame rails where they cross the wall bracket arms.  While the layout seems strong now, it may be better to bulk up these areas to help spread the vertical loading on an area wider than 1/4".

Underside of Mojave Middle Staging Yard panel looking east towards ladder.

This workbench area under the staging yard will be used as before.  The 13" clearance should be enough for my regular use of the space.  I have a light-table and other low profile items planned for this area.

Mojave Middle Staging Yard panel looking west towards West Mojave panel.

The panels are sitting pretty well with the wall brackets supporting them.

Owenyo #2 - Breaking Up the Plywood (MDF) Pacific

Many years ago layouts which were simply sheets of plywood with no dramatic scenic features were dubbed the "Plywood Pacific".  To break up the same syndrome settling in at Owenyo, a couple weeks ago I started making some changes to the western end of Owenyo #2 Module by cutting out a section to start the contouring terrain.  The land form change needs to start in #2 module because in the middle of the curve in #3 module, just west of here, there's a timber culvert under the main track that will need some place to drain.

Sketch of how the terrain falls away from the west switches in Owenyo.

This is also the first section of the layout that needs to start transitioning to 'cookie-cutter' benchwork and roadbed style to mate with the planned Owenyo #3 corner module  The construction of the Owenyo #3 module will be a full hybrid of MDF and Expanded Styrene Foam for the land forms and the 'High Line' NG trestle pit for the SG track buried down into the surrounding foam.  

The opening in the MDF cut for the foam insert.

I cut the top sheet of MDF with the table saw and then flipped the module on its edge to cut the corner.  These cuts allowed me to get the saber saw blade inside of the structural frame of the module to do the rest of the cutting.  I had some rough Sharpie marker paths to follow, but basically free-handed the actual cutting with the saw.  The edge was then finished a bit with a rasp to knock off any sharp edges.

CAD plan for Owenyo #3 with the "High Line" Trestle over the SG pit.

The grade down towards Mojave as soon as I can, possibly just west of the end of the Owenyo #2 module, as soon as I can make the vertical easement to the 1.5% down grade.  One of my major gripes with trackwork in general is not having proper vertical curves transitioning between different grades.  This can lead to vertical uncoupling on longer cars and engines.  Starting the transition to the grade earlier will also help with the SG pit track "dive" under the NG transfer trestle by cutting the vertical distance the spur will need to drop. 

Here's the view of the foam block cut out.

I cut the foam 5.5" wide and 20.875" long.  One corner had to be cut off to mate against the diagonal brace inside the module.  This will cut the available "hand space" to only what is below the diagonal rib in this area, but that should still be sufficient for my needs.

Dry-fitting of the foam block.

Always be sure to test fit pieces before putting the sticky gooy stuff on the pieces!  The piece was actually a good snug fit against the diagonal brace and west end-plate of the structure.

Gorilla Glue applied and a couple of the clamps in place.

Gorilla Glue expands up to four times its starting volume... so be sure to clamp the pieces of material together.  Also expect drips from the bottom as it pushes out extra glue!

I clamped both ends, and eventually two places front-to-back.  Two wedges were pulled together from rem's to support the bottom of the foam, which pushed against the Mojave Staging level below.  Two gallon jugs were placed on top of the MDF roadbed to keep the glue from buckling the roadbed upwards.

View of the module after the glue has expanded and dried.

The glue dried and did stick one piece of foam that I put under the right edge vertical clamp... so a few bits of white pop-corn foam are now stuck to the underside of the purple foam, oh well.

Eventually I'll probably do some forming of the foam down towards the profile I randomly cut in the MDF frame and blend it up to the MDF roadbed.  I was sure to leave enough MDF roadbed to mount the headblocks of the switches.  I could probably also rasp down the edge of the MDF as well, reducing the amount of 'fill' material I'll need to use over the foam area.  I guess we'll find out in a future installment!

What's Next?...

This post pretty well catches the blog up on where the layout is as of the 18th of March, 2021.  I'm looking forward to getting some track soon.  The next sections of construction without the track needs to be pointed at the three following areas:

  1. Decide on the alignment pins and bolt system to connect the modules, then actually build the jig and put the critical holes in the structurally finished sections of the layout. (Yikes!)
  2. Continue construction of the secondary structure under Owenyo #1 and push the structural support for the "removable wye and keel".
  3. Start construction of the Owenyo #3 module which will be a full hybrid of MDF and Expanded Styrene Foam plus a grade transition and the footings for the 200ft long transfer trestle!

In my CAD plan I start the grade as the track "rolls over" the edge of the grade just below the culvert.

This slight design change from how I quickly mocked the plan up in the computer should allow me to increase the length of the 1.5% grade and there by the vertical distance which I'll be able to get by the time the track reaches Mojave Staging below Owenyo.  

My rough 3D CAD model of the whole layout.

The CAD model shows about 5" and some change for a 1.5% grade, but that's with very conservative starting and ending points for the grade.  If I can extend the grade back nearly to the west switch at Owenyo and possibly even through the curved lead into the staging yard at Mojave, then I'll probably get at least another 3/4" of height (Edit: max of 1.2" assuming the following is true).  I've run the numbers again, a possible grade run of 480" and a climb of 6" results in an average grade of only 1.25%.  This gives me 0.25% to play with in terms of vertical easements and fudge-factor if I've made a mistake in my calculations.  I'd rather have a longer grade run and a slightly lower grade, just averaging the total climb over the whole path around the west, north, and east walls of the room.

I guess I've had enough 'simple' shown in these last two posts.  Nothing will be 'simple' from here on!  However, I'm not too worried about the next sets of challenge which await me.  The two small pits in Owenyo #1 module has let me see how the 1/4" MDF will respond to flexing.  Also the inserting of the foam and gluing to Owenyo #2 module has let me play with Luke Towan's MDF Frame and Foam Center construction method in practice.  I must say that it is very strong with the Gorilla Glue being used and properly clamped during drying.

3D CAD model of the structure I plan use building the Owenyo #3 module.

So I'm looking forward to changing from the simple 'box' construction of the first four panels and into the hybrid construction of the new section from a couple of road bed pieces, structural rails of MDF and precision cut foam sections glued in place filling up the sections in between.

In Closing

Stay tuned as I continue the construction of the SP's Jawbone Branch in HO scale.

Jason Hill

Related Articles:

SP Jawbone Branch (Part 16) - Brackets, Pits & Diagonal Joints - Construction of modules, supports, etc.

Jawbone Branch Index Page - List of all my SP Jawbone Branch modeling posts