Category Archives: Benchwork

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First Train Reaches Gilahina

It’s really amazing how long it takes to do things sometimes.  I honestly hoped I’d be where I am now almost a year ago, but hey, life gets in the way, right?

At least I’m finally making progress on the mainline.  As of 1900h tonight, the first train reached Gilahina – or at least where the new Gilahina bridge will be in the future.  Sure, the electrical isn’t complete that far out (power was provided by clip leads) and there really wasn’t any complex trackwork in that stretch, but I’m still happy that I’ve finally got mainline down and can run trains more than over a few switches.

Changing Contact Adhesives

Unfortunately I had a fair number of other things to do this weekend, so I didn’t get as much done as I really would have liked.

Typically for attaching N scale roadbed and track, I use DAP’s Weldwood contact adhesive. What can I say – it’s cheap and it works.  However, the stuff is a witch’s brew of organic solvents that – in addition to potential biological side effects – features prominent warnings about causing an explosion when being used, say, ten feet from a furnace.  During the summer that’s not an issue, since the furnace is shut down dead (and I have an electric water heater, so that’s not a concern).  Since it’s now winter, ventilating the basement adequately to avoid the “big boom” isn’t as much an option.  So I set out in search of a better adhesive that would be less likely to form a mushroom cloud in eastern Colorado Springs.

What I found was 3M’s Fastbond 30NF.  It’s still a polychloroprene contact cement, but the chemical engineering wizards at 3M have figured out how to make it primarily water-based, rather than all the organic solvents in most other contact cement.  It’s explicitly marketed for its nonflammability when wet.  In fact, the datasheet shows that it has no flash point – you literally can’t ignite it.  Sure, it’s also rather expensive ($100/gallon), but less so than blowing up your house.

The good news is that it works, and works very well in terms of bond strength.  The bad news is that “Fastbond” doesn’t live up to the fast part of its name.  It has a significantly longer wet stage than the organic solvent-based stuff, which is understandable even in such a dry environment as a Colorado winter.  I found that I usually had to wait about 20-30 minutes between application and actually being able to adhere pieces together.

The good news is that my concerns about it not bonding strongly enough (because, somehow, I assume anything not based on hideously harmful and/or flammable chemicals is inferior) were completely baseless.  The 30NF bond strength seems significantly stronger than the Weldwood, up and to the point that I had to put spacers down to keep the track from accidentally sticking when I was assembling the rail joiners.  At least twice I had a tie stick down so hard it detached from the rail when trying to get it up.  As long as it endures over time (and I have no reason to think it won’t), this stuff is superior from a bond aspect.

The other downside, besides working time, is that any frothy or clumpy spot will dry white.  However, most of that will be under ballast, and you just have to be more careful to only apply a thin layer to the bottom of the track.  Really it’s just about learning to apply more carefully than the “slather it on” method used in the past.

Nizina Yard

In 1915, the Alaskan Engineering Commission presented a report to then president Woodrow Wilson concerning the potential expansion of railroads within the Territory of Alaska.  If you want to read the report yourself, Google Books has it scanned and online.  Part of this was an exploration of potentially expansions to the Copper River & Northwestern, none of which were ever actually built.

The report proposes two branches from near McCarthy to other nearby mining districts.  One, a 14 mile branch, would extend around to the east side of Bonanza Ridge (the main Kennecott Mine was on the west side) up McCarthy Creek to the Mother Lode mine.  The other, a ~17 mile line, was proposed from McCarthy further southeast to the gold mining district along the Nizina River.

Because the Mother Lode Mine was on the opposite side of the ridge from the rest of the mines, eventually the tunnels were interconnected.  Mother Lode ore was sent through the Bonanza Mine to get it to the other side of the mountain, and then down the trams to Kennecott to be loaded.  There wouldn’t have been a reason to extend the railway around the backside of the ridge for it.  More interesting would be the Green Butte and Nicolai mines, which existed on the east side of McCarthy Creek, might have been able to use rail service.

The Nizina Branch idea is more intriguing, however.  Even while there was active mining at Kennicott, there was placer gold mining going on at Dan Creek, southeast of McCarthy and on the opposite side of the Nizina River.  Additionally, copper prospects had been described just a few more miles up the Nizina and Chitistone Rivers, along Glacier Creek.  So it’s slightly plausible that – should copper mining have survived in the district – that additional mines would have been developed on these prospects.  I don’t proclaim to be any sort of expert (or even novice of any note) in this area, but the US Geological Survey has a 1943/44 report on mining prospects in the Nizina District available as a PDF.

The short version is that I needed more traffic at the north end of the line to keep operations on the layout interesting.  I also wanted a test track above my workbench that I could use for working on equipment and programming DCC decoders.  Given that the workbench is just across the wall from McCarthy and Cordova, and that McCarthy was at just about the right height for a workbench branch, I decided the “Nizina Branch” would be born.  It will serve as staging for one empty coming up and one load going down each operating session.

The yard is three tracks wide, with the one nearest the edge being the DCC programming track in addition to storage.  Given that this is all just staging trackage, I used some leftover Atlas code 55 flex and turnouts that I had lying around.  You may notice an odd bit of 3-rail track near the end, as if I’d decided to model dual gauge.  Since I do spend a decent amount of time working on HO models for other folks, I needed the programming track to be compatible with both HO and N scale equipment.  So, using a few PC board ties and some extra rail, I built a dual HO/N scale programming section.  And yes, that’s a BC Rail B39-8 running around.  It won’t be part of the CRNW’s roster, but much like my IAIS ES44ACs, I’m rather fond of it and you’ll probably see it running around in “unofficial” layout photos.

The switch machines are, of course, my MRServo design.  They’re completely open source, but available from Iowa Scaled Engineering if you want to buy some.  The wiring is still a bit rough – I haven’t gotten it all finalized yet.  I was just happy to get the track power and programming track lines run back to the electrical panel with my limited time this week.


The Helix In Action

In between other projects tonight, I added another half-turn to the helix.  Figured I might as well enjoy it a bit as well, so ran a quick test train – just one of the SD60Ms (future CRNW 600), a half-dozen ore jennies, and a boxcar that was sitting on my bench anyway.  Figured out that an Atlas SD60M is good for about 20 cars on the 2.5% grade, based on a test I didn’t video.

Starting Trackwork on the Helix

Between Abercrombie Canyon and Chitina lies nearly 70 miles of some of the most remote, inaccessible railroad in North America.  Twisting and turning along the west bank of the Copper River, these miles would offer a great deal of scenic value, but little operational potential.  There was no industry through this stretch, and damned few people at all.  Those that were there consisted largely of native people, fishermen (largely in the lower canyon – there was once a salmon cannery around Abercrombie at MP 55), railroad workers, and of course the random outdoorsman.  From a modeling perspective, it would be miles and miles of track on a narrow shelf, perched between the mountainside and the swirling blue-grey waters of the Copper.  So,  as I needed somewhere to shift between decks, I chose these remote 70 miles to compress into the great helix.

The structure will be a 20 inch radius, 8 turn helix connecting the lower deck at 35 inches above the floor with the upper level at 60 inches.  This comes out to a grade of just under 2.5%. Inspired by other designs I’ve seen lately, I chose to use threaded rod as the main vertical supports.  It’s simple to install, requires no precision cutting on my part, and allows for adjustment after installation.

Threaded Helix SupportsThe basic design would consist of 8 sets of rods, each set 45 degrees apart and spaced by about 3 inches.  These would be mounted into a lower plywood platform and extend upward through each helix level. Thanks in part to the explosion of 3D printers on the market (which often use threaded rod for linear drives), 3/16-16 threaded rod is abundant and cheap. I picked up 16 rods, each 36″ long, from eBay for something like $40 shipped.  Nuts (part 90473A031) and washers (part 90108A032) were ordered from McMaster-Carr.

Helix 1/4 turn segmentThe roadbed itself would consist of 90 degree segments (quarter turn) cut from 1/4″ plywood, with ears at the halfway point for connecting with the rods.  Two layers of these segments would be installed for the track bed, 45 degrees offset from each other.   The segments are glued together using standard wood glue and clamped while they dry.  For the threaded rods, 5/8″ holes were drilled (very oversize for the 3/16″ rod) so that there was plenty of adjustment room.  I specifically chose large flat washers so that I could have large holes for fine-tuning the alignment.  Even though only the upper or lower roadbed segment is attached at each set of rods, this still provides a very strong roadbed once the glue sets and it’s bolted down.

IMG_1070 Starting the helix IMG_1067




Here’s a handy tip – turns out spinning a few Homemade nut spinnerhundred nuts down a few feet of threaded rod is absolutely no fun.  In fact, it’s downright maddeningly slow.  Fortunately, there’s a better, faster way to do it.  Just get a 4″ buffing wheel (meant for a bench grinder, maybe $5 at a home improvement store) and a short piece of threaded rod.  Put a big washer on each side and a couple nuts, pop that sucker in a drill, and you have a nut turner.  Makes very short work of spinning each nut down the rod.  About the only gotcha is the occasional string that gets loose from the buffing wheel and jams the nut, but that’s easily cleared with just your hand.

After that, it’s all just one step at a time.  Add a couple segments, then go back and lay track before you cover up a helix turn with the next one.  I typically have been keeping the track about 1/2 turn behind the benchwork, so that I can alternate between setting benchwork segments and laying track.

IMG_1080 IMG_1079To keep the grade constant, I built this handy grade measuring device out of a $3 Harbor Freight level.  Over a span of 8″, a 2.5% grade will rise 0.2″.  So, I had some hex cap screws lying around that had heads 0.2″ high.  I drilled a hole in one end of the level and threaded in a cap screw.  Ta da!  Almost a perfect 2.5% grade level.  I just place it halfway between each set of rods, progressively working up the helix as I build the roadbed.  I keep checking that the distance from one level to the next is a consistent 3-1/8″, but so far I haven’t had any issues using just the level method.  Once each piece is determined to be the right grade, I firmly set the nuts against the washers and the roadbed.

Helix Progress - 30 Aug 2014As of when I called a night tonight, this was the status of the helix – about halfway through the third turn.  The roadbed and track are both held on with my usual method of DAP Weldwood contact cement.  I’m out of plywood segments that have been cut, so I’m calling it a night at this point.  I’m taking Labor Day off to take in a baseball game (and then some – the Rockies still have three make-up innings against the Giants from a rained-out game last May, so tomorrow will be at least twelve innings).   Regardless, it’ll be a break from the basement.  I do plan to do some pull tests using a couple SD60Ms and ore cars to make sure we’re in the ballpark – no pun intended – of having the right grade for the trains I plan to run.

The Katalla Branch

Ever since I drew the original plans a year ago, I’d always had the idea that – should the CRNW have survived – that there might be a branch to Katalla.  As those familiar with the CRNW know, at one point Katalla was to be the terminus of the CRNW.  It had a key advantage for a burgeoning mining industry – nearby coal and oil reserves.  The town lacked one key feature, however – a natural deep-water harbor.

In reality, Katalla’s demise began with the federal government (under President Teddy Roosevelt) withdrawing public lands from coal mining in 1906.  Shortly thereafter, the lands were closed to timber and oil extraction as well.   Then, in November 1907, all of the Katalla dock and breakwater facilities were destroyed in a series of early winter storms.  With no available resources – save a single 160-acre oil field – and no facilities, the CRNW packed up and moved its terminal to Cordova.   Katalla would get a refinery to process the limited (but apparently high quality) crude it produced, but little other industry developed to sustain the town.  By 1933, when the refinery accidentally burned, there were reportedly only about 100 people still living in town.  However, that was the end – after 1933, Katalla would fade into history.

In 1971, however, new hope arose for industry in the Katalla area.  Thanks to the Alaska Native Claims Settlement Act and its effort to compensate the Alaska native peoples for their losses, the Bering River bituminous fields and the Carbon Mountain anthracite fields passed to the Chugach Alaska Corporation, one of the regional corporations set up by the ANCSA to administer lands transferred back to the native people.  In 1991, the rights to develop the field were sold to the Korean Alaska Development Corporation as part of CAC’s Chapter 11 bankruptcy proceedings.  KADCO has yet to do anything with these rights, and in fact several conservation interests have discussed buying them to prevent any future mine.

Further, the CAC obtained rights to try for commercially-exploitable quantities of oil and gas in the Katalla Field in 1982.  However, these rights were temporary, and expired at the end of 2004 unless a commercial well could be put in production.

In reality, no commercially viable oil well materialized, and the coal fields remain untouched since 1906.  However, with the idea that my modern day CRNW could provide both a customer and a transportation solution, I’m going to explore the idea that at least the coal fields were developed at a small scale.  Local coal seems a plausible energy source for both my processing plant at Eyak, the town of Cordova (which in reality today draws its power from both hydro and a large diesel plant), and the mine operation itself.  Plus, having another local job to run adds more operating interest than just the ore trains and wayfreights plying the mainline.

As much as I’d like the branch to have been developed in the 1920s or 1930s, I’d have to bend history around too much to make that plausible. If the Guggenheims and JP Morgan couldn’t get the Department of the Interior to change their mind about resource extraction in the 1910-1930 era, there’s no plausible reason to believe that it would have happened between 1930 and the transfer of the coal loads to the CAC in 1972.  So, in my version of the world, the Katalla Branch would have been developed in about 1972, once the dust had settled on the ANCSA.

One of the original 1913 Alaska Railroad Commission reports indicates that two routes were considered from the CRNW to the Bering coalfields.  Both would start near the Miles Glacier Bridge.  One route would run around the coastline to Katalla and then back up the Bering River.  The other (shorter) route would run up the Martin River delta, cross over near the foot of the Martin River Glacier, and then pass over some steep grades (estimated at 1.7-2%) and around the western shore of Lake Charlotte.  From there, it would reach the mines and could be extended down towards Katalla.  By 1972, with modern motive power, construction techniques, and the recently-reinforced knowledge of the powerful damage earthquakes could transform the coastline, I have to assume that the the mountain route via Lake Charlotte would have been used.  Plus, there was no reason for the Katalla Branch to actually go to Katalla by that point, as there wasn’t anything left of the town.

My other problem is rather pragmatic – I sketched in the Katalla Branch coming off the mainline between Alaganik and the Miles Glacier Bridge.  In reality, it would have diverged in this area, coming off the mainline after it had crossed the braided tributaries of the Copper on the north/east side of Long Island.  The problem is that’s located at the end of the peninsula on my layout, and I can’t come up with a good way to helix the track down at that point.  There’s just too much benchwork needed to support the peninsula to start putting holes in it.

I don’t intend trains coming off the branch to ever be particularly long – maybe 8 cars plus engines and caboose, to be roughly in proportion to mainline trains at 20ish cars.  Plus, back-of-the-cocktail-napkin calculations show that creating 200 tons of pure copper a day via electrowinning would take roughly 4-5 cars of coal per day, given typical generation efficiencies.  So if I could pull 8 cars out every op session, that seems reasonable to feed the whole shebang.

Enter the train elevator.  Basically a strip of track 55-60 inches in length, mounted to a wood carriage that rides on two linear rails.  A pair of stepper motors and jackscrews raise and lower the track between the two decks.  I intend to make it 99% automated, so that the train pulls in, power gets cut when it hits a sensor, and the elevator takes it to the other level.  From an operator’s point of view, they’ll leave Katalla Junction and disappear into the trees, and a minute or so later pop out of a summit tunnel or cut on the very lowest deck.

There’s absolutely nothing like it in the prototype.  I know and accept that.  I wouldn’t want one on the mainline – the main decks will be connected via a proper helix – but it seems an acceptable way to add time (otherwise the supposedly 38+ mile branch would only be maybe 15 feet long) and an easy connection to what amounts to a long industrial spur.  It gives me a plausible connection to local fuel producer, and a reason to run another local job every op session or two.

I’ve got the rails, the screws, and the stepper motors – now it’s just a matter of getting all the other widgets (screws, brackets, etc.), designing some controls, and testing it out.  I’ll let you know what comes of it.

Basic Benchwork Nearing Completion

I realize it’s been nearly two months now since I’ve added an update, but I’ve been rather busy.  For most of May I was actually out of the country, bumming around Germany, Belgium, and the Netherlands for fun and profit (or at least work…)

After getting back, I’ve been working on benchwork and more planning.  The upper valance deck is now all the way around the layout, the middle deck is complete right up to the Chitina Town Lake (where the helix will connect it to the lower level / Abercrombie Canyon area), and the lower deck is complete through the Miles Glacier Bridge.

None of what’s left concerns me all that much, except for the helix.  Helices and I have some uncomfortable history.  My last attempt – while functional – took about four times longer to build than I wanted, wound up being rather expensive, and lacked a certain something in dimensional stability.  This time I think I’m going to go with the threaded rod approach to spacing the decks, rather than trying to screw them all into a semi-rigid wood frame.  Stay tuned…

Lighting & Benchwork Update

Those of you who have been following along know that one of the core electronic pieces I’ve been working on for the CRNW is an LED lighting system tied into the fast clocks.  Over the run of an operating session, I want to transition from “dark” (really dim blue light) through the brilliant warm light of daybreak, the bright white of midday, and the through the golden hour and sunset back to dark.    The system will consist of the fast clocks – obviously – as well as a MRB-GIO to figure out color and intensity, and then a set of power booster boards that actually control the 2000W going to the LED strips.  The power boosters will be local, each controlling <20ft of layout, to keep the amount of power being switched to a more manageable level.

The prototype power booster boards for the LED lights showed up a couple weeks back, but this weekend was really the first chance I’ve had to try integrating them with the full system.  I connected one up to my test LED strip and mounted it back over Cordova, and then connected it to a MRB-GIO and did some basic programming to turn it into a lightning controller.

Results are promising – I need to do a bunch more tweaking on the exact light transitions, but my first try came off pretty well.  I also did a few tests using a bunch more strips to increase load.  The system was designed for up to 6A per channel, so I cranked it up to around that.  Heating was actually less than I expected – the board only slightly warm to the touch even switching 6A on a couple channels.

I’ve posted a few photos of the new power control board, as well as some samples of midday, evening, and night light.  Night isn’t that bright, I promise.  It’s just the camera evened out the exposure.

On the benchwork front, I did get the top deck extended from Strelna over to the north end of the Chitina yard.  The bottom deck is still being pondered – I’d really like to add a short Katalla Branch as a very low level.  The problem is that I can’t figure a way to shove a helix under where the junction should be.  I’m contemplating a train elevator along the wall (hidden behind the Miles Glacier Bridge area), since trains to/from the coal fields above Katalla would be short – 6-8 cars plus power.  Regardless, I’m still pondering it.

Oh well, off to Memphis for the week tomorrow.  I’ll figure out what I’m doing about a potential Katalla branch train elevator when I get back.

Smells Like Progress

While not feeling the greatest this weekend, I resigned myself to the basement and building benchwork.  As a result, the gridwork is now in place for Cordova-Eyak on the bottom level and McCarthy-Gilahina-Chokosna on the upper level.

Included in the upper level is the first major piece of depressed grid that will accomodate one of the four big bridges I plan to model  – the Gilahina Trestle.  (Photo linked from Don Bains’ Virtual Guidebooks site.)  The other three big bridges being the Miles Glacier / Million Dollar Bridge, the third Copper River crossing, and the Kuskulana Bridge.)  The current version is actually the second trestle – the original burned in 1916 and was replaced by the one we have today.  The structure is ~880 feet long and ~90 feet high on a ~15 degree curve (radius ~440ft.), with six piles per bent and extensive cross-bracing.  Today, it survives alongside the McCarthy Road in a deteriorated state.

For my proto-freelanced version of the CRNW, though, there’s simply no plausible way the trestle would have survived in service to present day.  A 100 year old high wooden trestle is just not up to the passage of heavy ore trains and 200-ton locomotives multiple times per day, no matter how well built or well maintained it may be.  Plus, the trestle forms most of a very sharp curve – much sharper than any reasonable mainline standard.  However, it’s such a stunning visual element along the line, and one that many people who have visited the area are familiar with, so I also can’t leave it out.  My solution is that the mainline will pass by in the foreground, atop a modern deck girder bridge constructed as part of a 1960s-70s era line change (exact date in alternate history to be determined), while the old abandoned trestle remains in the background.  Like many things in the wilderness of the far north, the old is often left just because it’s not economical to tear it down.  Plus, in this case its historical significance to the area in addition to its site within the the Wrangell-St. Elias National Preserve would lend to its preservation.

I’ve had to scale the Gilahina Trestle just a bit.  While 880′ in length, it’s only about 650′ on a straight line between the ends due to the sharp curvature.  (Distances estimated from aerial photographs.)  At full size, it would be approximately 4′ long and 6.75″ high in N scale.  I plan to keep it full height – hence the drop section to give me an extra 3.25″ to play with, but compress the length to about 3′, or 480′ in full size.

If anybody has measurements or plans for the Gilahina Trestle, I’d greatly appreciate hearing from you.  Otherwise I’ll have to head back north and spend some quality time with just me, the trestle, a tape measure, and an ultrasonic range finder.

Here’s a couple shots of the new benchwork grid, including the drop section for accomo


In addition, the Fast Tracks jig finally arrived, and I’ve been practicing at building turnouts.  So far, I’ve built two – one right and one left – and I don’t think I’ve quite gotten the hang of it yet.  Both are usable, but not quite as perfect as I’d like – particularly in the area of getting the point rails just right and making the throwbar move flawlessly.  (I seem to always get the point rails stuck on the stock rail when soldering them, and can never get it deburred once I separate them.)  Also, the FT#7 is a bit bigger than the Atlas #7, leading me to believe the Atlas #7 is really more of a #5-#6.  I’ve put my second attempt next to an Atlas unit so you can do a size comparison.

fasttracks first-scratchbuilt-turnout

Until next time…

Happy New Year!

Like any good model railroader, I spent New Years Day in the basement working on the layout.  I was hoping my Fast Tracks jig would arrive on New Years Eve, but alas, it did not.  So, I reverted to working on lighting, benchwork, and some electronics design.

The good news is that the entire layout room now has proper room lights – nine fluorescent 4′ dual T8 fixtures, to be exact.  It makes it much less of a dingy hole in the ground and much more a presentable layout room.  Now if only the construction disaster would clean itself up…

As far as benchwork, I accomplished a piddly 32″ – the upper deck between McCarthy and the Kennicott River crossing.  The electrical took longer than expected, and I needed to accomplish some design work  for Iowa Scaled for a new optical track detector we’re working on.

My goal for the rest of the week is the rest of the east wall (McCarthy to Kuskulana on the upper and Cordova to Eyak on the lower) and – if the stars align – the rest of the wall framing and clean up some of the random junk in the way of progress.  We’ll see what actually happens.