IT’S MAGNETIC!

One of the critical tasks preparing for operations has been completing installation of uncoupling magnets.  I am using Kadee 308 under tie magnets for uncoupling in difficult to reach spots.  Permanently mounting these magnets under the ties can lead to undesired uncoupling, so all are mounted on trap door (hinged) hatches.

Preparation for the magnets began with cutting holes in the cork roadbed and plywood subroadbed at the desired locations. 

Uncoupling magnet hole in roadbed.

The holes were then covered with styrene covers.  I used 0.020 inch thick Evergreen black styrene for the hole cover and Evergreen dimensional strip for the cover frame, matching the roadbed height.  I used black (vs. white) styrene to be less noticeable should the eventual ballast cover get disturbed.

Uncoupling magnet hatch covers.  A Kadee 308 magnet and steel field enhancement plate are nestled in the left hatch cover.

The holes were cut and hatch covers were mounted as part of the roadbed preparation before track laying.  The hatches received the same gray latex paint used to prepare all roadbed.  <Note: recent discussion on a Yahoo Group List points out that latex paint “breathes.”  I accept that my roadbed painting is purely cosmetic.  It won’t slow the drying out of the cork.>

With initial operations looming soon, I needed to complete the magnet installation.  As seen in the photo, a typical installation involves mounting a small plywood hatch to the underside of the subroadbed with a hinge.  A corner brace mounted on the side provides a lever arm for actuation.  Airplane control rod (plastic “choke cable”) provides the linkage to a knob mounted in the fascia.  Pulling the knob pulls the magnet hatch up into position.  Pushing the knob back in lowers the hatch, reducing the magnetic field, hopefully preventing unwanted uncoupling.

Typical magnet hatch activation installation.

Two spurs in Springfield are far from the aisle, close to the backdrop.  The team track ramp also might be difficult to reach, so all three get the Kadee 308 magnets.   The Eugene depot tracks are a long reach from the aisle, so many magnets are mounted there.  Further motivation for magnets on the depot tracks comes from providing for some passenger car switching at the depot.  Passenger car diaphragms are notorious for getting in the way of any other uncoupling method.   I’ve added magnets for both switch ladders in the classification yard, even though both sites are within easy reach of the aisle.  The Eugene depot and classification yard complex has sixteen uncoupling magnets mounted.  About half of those were challenging installations.  Still, one learns and develops a set of techniques used for most installations.

Chalk up one more “Must Do” task on the way to bringing the railroad into operation.

EXPANDING THE WORLD

I continue to work both below and above the benchwork on the layout.  Below the layout, I connected the first pair of boosters to the DCC system command station.  A pair of NCE PB5 boosters complement the existing 5 amp PowerHouse Pro.  I’ve been running mostly sound-equipped locos on the layout.  Start-up produces a slow wave of sound coming on as each sound system grabs available power.  The boosters were planned long ago. 

I encountered a minor fault as I hooked all of this up.  An issue with DCC boosters is that they might be out of phase with each other, leading to bad behavior at the boundary between booster districts.  Using an AC voltmeter, I checked each of the booster district boundaries and determined I did not have an out of phase issue.  With that, I ran the first pair of locos over the boundaries.  Crossing one boundary, I encountered a brief short and then resumption of movement.  The PSX circuit breakers were tripping and resetting.  Investigating, I discovered a 1.5 volt difference across the boundary.  I eventually traced this back to the booster power supply where I discovered one of the power supplies was inadvertantly set for 12 volts versus the 13.5 volts normally used for HO scale. 

NCE replaced the PB105 booster with the PB5 in their line this past year.  In contrast to earlier practice, the PB5 comes with its own power supply.  That power supply has a switch between 13.5 volts and 12 volts.  Check your power supplies for PB5 installations!

Above the layout base level, I have started benchwork RR-West of Oakridge.  The mountain climb starts immediately.  I also have another bridge, across Salmon Creek, to provide for as the roadbed starts out.  For the mountain section of the layout, I elected to use spline roadbed.  I am using nominal ¼ inch thick hardboard, cut into 1 inch wide strips.  These are mounted vertically, forming 1 inch thick roadbed as the splines are added for width.

Mainline climb out of Oakridge on hardboard spline.  Multiple spline laminations can be seen on the end of roadbed on the right.

The mainline bridge over Salmon Creek consists of four deck girder bridge sections with a ballasted deck on top.  That ballasted deck has depth that must be accounted for with the splines.  I am running three splines through the middle of the bridge girders.  I will place the ballast deck on top of them and then come back later to attach the girders as scenic fascia on the sides of the central roadbed splines.  The ballast deck will be composed of scale 12x12 inch cross beams overlaid with scale 4 inch thick planks (actually just 0.040 inch styrene).  I made a quick height tool for this assembly to help position the bridge splines.  The center spline at the Oakridge end fits into a slot in the plywood roadbed.  The first riser at the RR-West end has a notch routed into it to accept the lower spline height for the bridge, while allowing outer splines to be mounted at the correct height for regular roadbed.

Mainline Salmon Creek bridge roadbed.  Bridge center splines are depressed to account for depth of ballasted deck materials.  Regular roadbed height splines can be seen glued to the outsides of the bridge center splines at a higher level.

Once the bridge roadbed was accounted for, I built up spline roadbed around the curve in the corner and continued climbing through the “Pryor” area.  Actual Pryor has a siding, but I am using its name to identify the area I am working through.  I set the height of a far (eight feet beyond the last center spline riser) riser using a board and level.  I find the “old” method of using a spacer block on the low end of a bubble level to be more effective than the fancy new electronic level.  I still use the electronic level as part of a final check.

Roadbed spline laminations climbing up through the “Pryor” area.

As seen in the photos, I added a corner cove for the backdrop through the corner.  The corner cove is set at a height to provide for benchwork for Cascade Summit above it. 

This roadbed expansion will permit most of the first train-length detection block RR-West of Oakridge to be installed.  This should provide options for the initial test operations of the Valley Core.