Oct 26, 2011

In Which Steven Discovers Capacitance

So, weather's colder now, and I've still got issues with the newly-installed Digitrax DCC system.

The issue at hand is that my BD8 block detectors (from The Signaling Solution), which I love and which worked flawlessly with the old Keller OnBoard command control system, were now working oddly.  A train would move into a block, the detector LED goes on, and all seems well.  But when the train left the block, the LEDs were stuck 'on'.

Well, after checking for the usual stuff - ground loops, or other sources to cause current to flow through the one of the side of the feeders being used with the detectors, I did the unmanly thing and asked for help.  In this case, the designer of the BD8s.

I received a very quick and thorough return email, which suggested the problem was the DCC signal in one feeder causing a small current to flow, through capacitance, in the other feeder.  The solution was to put some distance between the feeders, physically, as much as possible.

This was a bit discouraging, as only the blocks with the longest wiring runs were experiencing problems, and those were (inevitably) the hidden and least-accessible sections.  You know, the part that runs thru the bathroom walls, thru the basement stairs, behind the furnace, and so on.  To keep wiring neat in these locations, the wiring had been neatly bundled together and carefully routed.  But the bundling was causing the problems - the alternating DCC signal in one wire was inducing a charge in the other wire.

I did color code everything rather religiously, so I crawled under the layout and started tracing the white and gray wires, which is the Rail B side (for me) and being used for detection.

Very long story short, I was able to pull all those wires out and re-route them (still neatly) along new paths that (mostly) kept them a couple inches or so away from the Rail A sides.  After finishing half of the first block (a hidden track beneath Durango), I ran a test train, but no change.  I continued working, got the entire run separated, tentatively ran another test train... and WaaLaa!  Properly functioning signals again!

After much crawling and re-wiring, I've now completed about 5 of the 10 or so affected blocks, and these changes have fixed all of them.  It seems almost crazy that just moving a wire run a little would makde a difference, but with DCC it certainly does!

Oct 14, 2011

RGS #20 restoration continues

Linn Moedinger posted here that work on the restoration of RGS #20 is continuing, with lots of tender issues being addressed. The bottom portion of the tank has been replaced by stainless steel, and will be riveted to the repaired top section. The tender frame has been repaired, as well as the trucks, wheels, bearings, etc. Bearing work is also ongoing with the locomotive, and its wheels still need cracks repaired. The firebox is installed and stay bolts are being put in place; the smokebox is also being installed. The boiler will be installed after the smokebox. In a neat move, the main air reservoir wasn't usable so a new one was fabricated, and placed INSIDE the old one (to maintain the original appearance). Linn also notes that donations continue to be needed to fund the work; those are being handled through the CRRM.

And in other news,  I've finally updated my Links page, and the got the Events section current.  I've only got four shows listed there at the moment, and only 1 is directly-narrow-gauge related.  If you know of other events, let me know and I'll add them.

Oct 10, 2011

Weathering continues while the weather holds

When I'm not fixing things around the house, or trying to keep up w/ life, I've been working on updating the website (STILL replacing links from the Denver Public Library) - it's amazing how many Otto Perry shots I've added to my Rolling Stock page... lots of images of many of the K-27s traversing the railroad in the 40s.  I'm about 1/3 thru the 564 photos of the RGS that Otto has on that site.

I'm also trying to finish up the weathering of my stable of Bachmann steamers, with decals, and then layers of dullcote and weathering powders.  I live in IL, and it's about to get cold, wet, and nasty here for the next (cough) months.  Since I don't have a spray booth, spraying happens only in good weather.  That said, it's been amazing here lately - sunny and low 80s - for over a week!

I've also just pulled out an older Sunset brass steamer, and disassembled and starting the weathering process on him.  This is a gloriously-detailed brass model, but i've never really finished the work to make it operational.  It needs weathering, but also electrical work, more weight, a headlight, and other stuff. 

And finally, as the cold sets in, I'll havae to work on DCC conversions for all of these, including working on or adjusting the phosper wipers on all the Bachmann locos, which (mostly) seem to be slightly out-of-place.  This is kinda scary for me... I've never managed to establish a good working relationship with brass axle or driver wipers.  But, I gotta try - these are great runners but need great pickup as well.