Progress, and making the transition….

 

 

Turnouts test-fit in place but not spiked down at the east end of Santiago Yard.

Having found a little time to build turnouts and lay turnout ties down, it’s time to lay the yard tracks that will store cars at Santiago Yard.

I want to use thinner ties in the yard tracks than are used on the main track, to simulate the yard tracks being lower than the main track of the Campbellford Sub.  Along with the use of Code 55 or Code 60 rail representing 80- or 85-pound per yard rail in the yard tracks compared to the Code 70 rail modelling 100-pound rail on the main as well as the use of cinders in the yard tracks versus gravel ballast on the main, the purpose of the different tracks should be plainly visible to even the casual viewer.

Following CN practice, the main track uses scale 6″ thick by 8″ wide Micro Engineering ties; turnouts use scale 7″ x 9″ Mount Albert Scale Lumber turnout ties. The yard tracks will use Campbell Scale Models and custom-cut scale 4″ thick by 8″ wide ties.  Campbell to my knowledge no longer makes their excellent HO scale ties, but I can cut similar ties from Mount Albert Scale Lumber HO scale 4″ x 8″ stripwood stock, which I buy in bulk.

The difference in tie thickness is negligible between HO scale Mount Albert and Micro Engineering ties, both being about .082″– ,085″ thick.  I need to make a height transition between these and the scale 4″ .044″ thick Campbell ties.  As well, the difference in height between Code 70 rail in turnouts and Code 55 or 60 rail in the yard tracks must be addressed.   Vertical curves, though with a total difference in rail top height not more than about .050″  between turnouts and yard tracks, still call for some planning to ease the transition between ties thicknesses and rail heights.

Four-wheel-trucked diesel locomotives or four-wheel driver steam locomotives are very tolerant of vertical curves.  Not so for eight-coupled steam like a Mikado, or at most a Northern.  A CN Northern has a wheelbase of twenty feet for the drivers alone; a Mikado which I will run on the Midland’s grain trains far more often has a fixed driver wheelbase of about sixteen feet.  Fortunately there is enough vertical play to let the lead and rear drivers drop a little to start into vertical curves.

I measured some sample Campbell, Micro-Engineering, and Mount Albert ties to determine their thickness.  The prototype railways set the ties into the ballast and raises or lowers them to make up differences in desired track height; we modellers don’t have that device to use on our layouts.  I also measured the thicknesses of regular 20-pound paper and a standard 3 by 5 inch index card.  Also measured were the thicknesses of some scale lumber in one- and two-inch thicknesses.

Wanting a replicable formula for use on the layout, I calculated the thicknesses of various combinations of card, paper, wood and track ties to deduce some tie thicknesses and shim combinations to make a smooth transition from thicker ties to thinner ones.  The above sheet shows what I came up with initially.

I used a home-made 16-tie-per-33-foot-rail tie spacing jig to place some yard track ties.  Ties 1, 2, and 3 are Mount Albert scale 7″ x 9″ wide ties; ties 4 through 13 are intended to make the transition to ties 14 through 18, which are .044″ thick scale 4″ height Campbell yard track ties.

Combinations of paper strips, scale lumber, and ties were white-glued together using the determined dimensions in my calculations on the above sheet to obtain suitable tie thicknesses for the planned tie height transition. I measured the thickness of each tie/shim combination using a digital vernier caliper to determine the total tie thickness before placing it in the tie jig.

Above the tie jig are some of those strips of scale lumber, paper, and card used as shims under the ties.   The bottom of ties 4 through 13 are marked with each tie’s measured thickness.  I found that even the white glue added a few thou to what was the calculated thickness of many ties, calling for some re-placing of the shimmed ties in the jig.

Next step will be to make some more shimmed ties of various thicknesses and try this out at the diverging end of a turnout in Santiago Yard.  And I have not figured out the rail transitions next, so there may be a few tie height tweaks to come.  This 1925 CN standard rail distribution diagram may help.

 

Advertisements

Cinders redux

Cinder-ballasted track on the York-Durham Heritage Railway at Uxbridge, Ontario.

I’ve seen a lot of cinder-ballasted track over the years.  Cinders were a cheap form of ballast from coal-burning locomotives’ ash that was used extensively on railways in the steam era.  It was as near as the the loco ash pit at engine terminals, and the price was right.

Test section of ties on a length of 1″ x 2″ pine.

I want to compare various methods of modelling ballast, so made this short section of ties using my standard yard tie spacing of sixteen ties per 33′ length of rail.

Woodland Scenics’ cinder ballast.  I ground this ballast to a finer texture in an old blender; it’s not as fine as I’d like it to be.

I was scared of using real cinders as I’d found the stuff to be attracted to a magnet when tested.  So I ground up a mix of Woodland Scenics’ cinder and other ballasts in an old blender made redundant when my wife got a new one.  I dyed the wood with some leather-dye-and-alcohol tie stain to impart some darkness to the roadbed before gluing on the ballast.

I painted on some matte medium, and immediately dropped the Woodland Scenics’ ballast mix onto the spaces between the ties.

But I found the ballast to appear a bit coarse in appearance compared to the real thing.

Back to basics.  A bag of sifted fine real cinders, matte medium, and a dollar store paintbrush.

I had collected some cinders from a local railway yard.  I sifted them through a mesh strainer–not the good one from the kitchen, rather a dollar store item.  I wound up with a nice bag of very fine real cinders.  But I did not care for stray particles of ballast being picked up by a magnet–loco motors may do the same thing, to the detriment of the motor.   So much for that!–I thought…  It turned out that my fears may have been unfounded.  UK EM gauge model rail club Shipley Model Railway Society — http://www.shipleymrs.org.uk/index.php — uses real cinders, and reports no problems with their use.

UK magazine Model Railway Journal recently ran an article titled “Modelling one of Britain’s least photographed stations” in MRJ #176.  Author Frank Davies of the Shipley club writes —

“It was our quest to effectively model scale ash ballast that first caused me to coin the term ‘extreme modelling’ for the Clayton project.  We had already discussed that the best way to represent ash ballast was to use graded fire ash which can be readily obtained from any of the steam preservation lines around Yorkshire, but processing it to produce scale ash ballast is a different story.

We initially intended to prepare the ballast using a mortar and pestle to break up the large pieces.  We then tried using a pepper grinder to create finer granules and graded the ash using a plastic tea strainer.  Not only did it take hours to create just half a jar, but we destroyed three grinders in the process.  On the plus side we were able to determine that the resultant ballast was exactly what we had been looking for.  Given the size of our layout, it was impractical to produce all the ballast needed in this way.  We therefore owe an enormous debt of gratitude to the Environment and Sustainability Institute (ESI) of Exeter University………Cambourne School Of Mines who generously agreed to process our ash using specialist equipment normally used for preparing mineral samples for research.  

Frustratingly, the traditional use of diluted PVA glue to fix the ballast doesn’t work with ash; instead we are using small artist’s brushes to paint slow-drying polyurethane varnish around the sleepers and the ash is then sprinkled through our trusty tea strainer onto the ballast.  Once dry, the surplus is removed using a dedicated vacuum cleaner so that the recovered ash can be be recycled.  This process is repeated until the desired depth of ballast is obtained.  Finally, the sleeper tops are cleaned up with a Stanley knife blade as preparation for installation of the rail and C&L chairs.” 

While my cinders are not ground up from the real thing but instead sifted to fine particles, I thought this technique worth another try.  I painted some matte medium between the ties on my sample roadbed, dropped some sifted cinders on, and voila!

I like this!

Passing a powerful magnet over the completed ballasting work removed a very small amount of fine metallic dust–but nothing that would be too detrimental to motors.  Most dust appears to be trapped by the matte medium.  Besides, just about every loco that I run either has a can motor sealing the motor magnets from outside materials, and/or is high enough off the rails that any material remaining after sweeping the track with a magnet would likely not be picked up by the magnets.

A trip back to the real Santiago Yard site east of Lindsay will happen in the next week or two, where I’ll collect some more cinders, sifting it to a fine, almost useable, material on site.  No sense in taking home what I can’t use.

 

 

Where were we?

Looking west at the site of Santiago yard, circa 1975.  CN steam loco 6060 is on an excursion train about to cross Lindsay’s “Black Iron bridge”. To the right is the main track of the Campbellford Sub., with the flat area to its left being the location of Santiago Yard’s three tracks, taken up in 1964.  –photographer unknown.

I’d left this off a few months ago as I got swept up in other things.  Back to some modelling.

The piece of layout that I’m building representing Santiago is a foot wide.  The main track and three yard tracks still leave about six inches’ room for scenery, primarily on what is the north side of the yard.  The above photo shows a small hill north of the main track. I would usually employ plaster-and’cardboard “hardshell” scenery construction, but decided to use Styrofoam this time around for its lightness and resistance to damage.

Fitting 1″ thick blue Styrofoam insulation to create landforms.  Yellow carpenter’s glue bonds these quite well to each other and the wood roadbed, etc.

I’m following CN practice for roadbed profiles.  Here’s 1939 CN Standard ballast sections showing a slope of 1.5:1 for ballast slope on roadbed edges.

Something that I want to improve on in my own modelling is to accurately model ballast sections and landforms.  Excessively sloped landforms would fail quickly in heavy rain and look contrived on a layout.

CN 1939 Standard Roadbed Cuttings and Embankments diagram.  Note again how gently sloped railway embankments are compared to those as modelled on some layouts.  

A knife purchased at the dollar store (Styrofoam will dull a good knife quickly) is used to rough cut the Styrofoam sheet to suit the slightly undulating land around Santiago Yard.

A steel bristle brush is used to smooth landforms and cut ditches next to where the track will be.  Behind the brush is the start of that small hill to the north of the yard. A regular full-size wire brush will remove material quicker.  This work will create Styrofoam dust–keep the vacuum cleaner handy!

Some 80-grit sandpaper smooths landforms to suit. A ditch north of the main track is being modelled here.

There was a fair bit of sanding, fitting more Styrofoam sheet to the layout, and filling to come….