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Puckdropper has scored 287 goals and 347 assists in his lifetime.


The tip is grounded, forget working on live track

Tired of buying new soldering irons when the tip would go out in less than two years, I bought a really good quality one. The club layout had a bunch of feeders dropped for the track around the roundhouse, and it was time to hook them up.

Once the soldering iron was hot, I fluxed the joint and touched the tip to the live* bus wire. Sparks started to fly and I realized working on the bus wire with a grounded tip wasn't going to work. Good thing the club's iron isn't grounded.

*Yes, live. DCC track voltage is around 16V, with usually around .5-1A current draw. It's also very short circuit tolerant, so there's little risk working on live DCC track.



How deep is your roadbed? How long is your drill bit?

I had to drop a new feeder the other day, and came across a problem. The roadbed is a very deep 3 inches, and most drill bits that fit 16 gauge wire bottom out well before that. I'd either have to find a longer (and larger) drill bit, or find another method of making a hole.

The other method turned out to be a nail. With no hammer in sight, the nail had to be pushed through the homasote. The resulting hole was quite a distance away, leaving quite a bit of the feeder visible. The track now has power, but the wire is a little unsightly.

I should have gone for the larger drill bit. There's two things to learn from this story: Don't make your roadbed so deep a special drill bit is required to drop feeders and if you do make the roadbed that deep, you might as well go for the larger drill bit.



Reflections on building a yard

Recently, I completed the trackwork of a 5-track classification yard. The yard follows as many of the 10 Commandments of Model Railroad Yard Design as possible, but made some mistakes and have a list of things I'd change if I was to do it over again. This post will address what was done well, and what was done poorly.

Done Well:
* Peco turnouts for local control. There's no confusing ground throws next to adjacent tracks.

This is a problem at the club layout. There is a ladder track and a ladder bypass track with a couple sidings off it. Sometimes someone goes to throw a turnout on the ladder track and accidently throws the one on the bypass track! It's even worse when there's another train on it. One of the advantages to the Peco is the positive snap throw, so no ground throws are necessary. You can't throw the turnout from above with a train on it, and the turnout that you're throwing is guaranteed to be the one you want to move.

* Every piece of rail is soldered to either another piece of rail or a feeder. Save dirty track, there is no reason a locomotive cannot get power.

The recommendation was made on the Wiring for DCC website. Rail joiners are relied upon for alignment only, and not relied upon for power transfer. While a large percentage of the rail joiners installed on a model railroad won't fail, enough do to cause headaches.

Another benefit is due to the sheer number of feeders, the power system is very redundant. Should one feeder fail, there are still several others that are working. (While rare, this does happen.)

* The yard wiring is done logically and documented for work later.

All feeders follow a color code, black goes on the back rail, and the colored wire goes on the front. There are different colors for classification tracks, arrival/depature and escape tracks, and the yard leader. This makes looking at the feeder underneath all one needs to do to figure out what track it goes to.

The wiring has been documented, showing where all the bus wires are and where all the feeders are. The feeders disappear because of the paint, so if there's ever a problem the diagram shows the approximate location.

* Tracks and roadbed were painted, providing a uniform look.

Two different manufacturer's tracks were combined in building the yard. Since they're two different alloys, there's a noticeable difference between them. By painting the track a uniform look was achieved, and it took the yard from being a collection of parallel tracks to a yard. Forget weathering freight cars, weather the ground they stand on!

* The longest track is the Arrival/Departure track.

The arrival/departure track is supposed to be as long as your longest track, so I simply made my longest track the A/D track. There's an escape at the end for power to be cut off, while the switcher begins work on the rear.



Done Poorly:
* Not enough room for tracks.

The yard base was built for the yard plan, but the plan didn't show how little space there actually was between the rail cars. There's only 2-3 scale feet of space between cars on adjacent tracks, way too little. I had used Peco Medium turnouts end-to-end to form my yard ladder, and based my track placement off of that. This means that cars will have to be uncoupled from above, or by using the "delayed uncoupling" feature most knuckle couplers allow.

Should a derailment occur, the derailed car will have to be pulled out to the lead and rerailed, then put back. All the more reason to make sure there's enough room betwen your yard tracks!

* Not enough room for yard buildings.

The benchwork ends shortly after the yard tracks, so there's no room to add yard buildings such as an office or storage sheds. Also, to maximize aisle space, the benchwork follows the yard ladder, leaving little room for scenery details such as vehicle access roads.

* No temporary lead was installed before testing, making movement of cars difficult.

While not a design error, this is a building error. Before painting and ballasting, if a temporary lead track had been installed and some switching attempted, I might have noticed the lack of room between tracks and been able to do something about it. As it was, the tempoary lead was only installed after most the work on the yard was done.

* Built the yard with no wiggle room inside the room itself.

I had to shorten some support girders in order to get it to fit. It would have been better to build the yard in two sections, the yard lead and extending tracks. (This has the added benefit of allowing the yard to be easily extended if space allows.)

I also measured max distance along the floor, and did not account for fixed objects such as window casings or outlets that stick out more than the base moulding. When the time came to install the yard benchwork, it was slightly too long to fit in the room.

* Painted and ballasted the track without coating the top of the rails with some removal agent.

This was a mistake! The paint and glue stuck to the rails and held fast. I tried cleaning it off with a wire wheel on a dremel tool, and that worked only marginally well. Brute force with a track cleaning block didn't work either. What finally worked was applying mineral spirits to the rail heads (sometimes multiple times) and then cleaning off anything that wasn't shiny with a track cleaning block.

* Too much ballast

Ballast is a necessary thing on model railroads, as it tends to keep tracks from moving. When I ballasted the yard, however, I got way too much ballast in the turnouts, and had little pieces of ballast fouling up the whole works. One piece of ballast was hidden in a turnout throw rod and kept the turnout from throwing all the way. It took days to figure that one out; that piece was hidden well.

Undecided:
* Rails were cut near the turnouts and immediately soldered back together in order to provide a point of release if the turnout ever needed to be removed. While this has the desired effect, it's not easy to solder rails together without the use of a rail joiner to keep them aligned.



Tip: Measure, then build smaller

When building a layout to fit between house walls, measure the distance between the walls at the point that sticks out the furthest (any trim, outlets, etc) and then build your layout slightly smaller. It might come down to modifying either your layout or the room to make it fit.



This post has been edited at 2008-10-13 02:21:26



Upgrade to Version 0.7!

Version 0.7
-----------

1. Colors are set by using define now, no longer by assigning values to global variables. (As a positive side effect, I deleted about 50 source lines.)
2. Added new color definition for warning messages.
3. Common user messages are stored in a single file.
4. Usernames are now stored unencrypted in the database.
5. Database access information is now stored in a seperate file. -- Repealed
6. New Feature! Installation.
7. Missing database is detected on the index page and an error message displayed.
8. New API functions! display_status_message($statustext) and display_error_message($errortext)
9. Rewrote index.php page to make the post selection and display functions much clearer. Also, the "View next X entries" and "View first X entries" behave a little more intelligently.
10. Added new option to decide how many messages to display on main page.
11. New Feature! Installation on a single database! (You will have to install the code in a new folder.)
12. Avoided stray capitol letters. Honestly, what's the deal with these case-sensitive languages?
13. Integrated in to web page. Basic direction is done via header, website navigation via footer.
14. Database access information now NOT stored in seperate file. Change #5 is repealed.
15. Blog version is stored in the database and updated with the database.
16. New Feature! Changable Options! (Right now, you can only change the number of messages displayed on the main page.)
17. Changed position of Goals Scored message. (A side effect of Version 0.6's login status code.)
18. New Feature! Record of goals scored!
19. Fixed security hole where one installation's login status transfered to anothers.
20. Fixed mistake where all radio buttons on the delete category page would have the "checked" property.



Expansion

I'm expanding my model railroad by replacing the old one with a new one. This time I'm doing things differently. The modular design is being replaced with a sectional design, the storage underneath is being made more useful, and some consideration is given to "human factors."

The previous layout was built with a modular design, with the goals of making it easily moved and able to be displayed at a train show. The layout never got finished enough to even consider displaying at a show, but it did make several moves easily. The new layout is still intended to be able to be moved from house to house, but it is not intended to be taken to shows. This means longer sections and fewer mechanical and electrical connections.

Storage underneath the previous layout consisted of a plywood shelf about midway between the floor and the underside of the layout. This simple shelf also braces the legs of the module. Unfortunately, the design of the shelf tends to lead to large boxes and other heavy, bulky items being placed on it. These items must be removed if access to the underside of the layout is required. The shelves are being replaced with "tool chest" style cabinets, where the cabinet consists of drawers inside of a larger box on casters. When access to the underside of the layout is needed, the cabinet can be rolled away.

Human factors are things external to the layout operation that make the layout more enjoyable. Aisle width, aesthetics, and an elbow/cup/tool rail are all human factors I've considered in the new layout. An aisle width of 3' is standard, with a few small locations that have less than that. Aesthetics have been considered with painting the benchwork. Rather than an unfinished wood, the benchwork should appear to disappear into a sea of gray. The focus will be on the layout itself, and not what's underneath. One of the other human factors considered was that of a cup rail. This is a railing around most the layout for cups, elbows, and tools, to try to keep them off the layout. Were it padded, it would provide a first line of defense in minimizing rolling stock damage.

There's more to a model railroad than just the track plan and scenery. Factors such as benchwork design, supplemental storage, and human factors can make a huge difference in how a layout turns out.



Upgrading to DCC

Upgrading to DCC

Recently, I upgraded my home layout to Digitrax DCC. The upgrade was easy, I had trains running after connecting power to the command station and connecting the track to the command station. Setting up a programming track was a little more difficult, as I wanted to use the programming track as a siding as well. All I had to do was connect the track and programming track outputs to a Double-pole Double-throw switch. Switching between siding and programming track mode is as simple as throwing the switch.

The block wiring remained largely untouched, and is still usable. There's no reason to remove it, but several to leave it in. Perhaps the most important reason is isolation is much easier. If a problem develops there's no feeders to remove or cut, simply throw a switch. Plus, if you decide to install circuit breakers, the blocks are already gapped and cut.

I got a little overzealous with wiring, and added a run out to my test track in the other room. This included the loconet wiring necessary for selecting and running locomotives. Loconet uses the same wiring as standard phone wiring, so 6 conductor phone wire and normal phone jacks are all that's necessary. (It's probably not a good idea to plug a telephone into a loconet jack or a throttle into a phone line.) I need to add a note on the main control panel as a reminder that an isolated track in another room is controlled by DCC.

Overall, the entire process was easy. If a model railroader is able to wire a layout with block wiring using conventional DC, they'll be able to connect a DCC system. Running trains is also easy, but programming is a little more difficult. All in all, it's a worthwhile upgrade.




Metal Wheels and Metal Weight

Some metal wheels have enough free play to touch metal weights located under the car. If this happens it could cause a short, or in some cases start a fire! To prevent this, cut a thin piece of styrene the size of the weight and install it between the wheels and weights. With most cars, this won't change your coupler height at all.



Sagging Couplers

I've recently been dealing with sagging couplers. Sometimes I can simply remount the coupler in the box, and everything's fine again, but other times I'm required to replace the sagging coupler all together. Some have suggested that shimming the end of the coupler can solve the problem, but I have had issues maintaining free movement when shimming with 0.010" styrene.

I like the "whisker" centering spring in many non-Kadee couplers, but usually wind up replacing them with Kadee couplers. The big advantage here is that they're all metal, and minor repairs are possible. Kadee's been advertising their whisker couplers in MR recently, so I might have to get a set.

If I get another manufacturer's couplers, such as McHenry, I'll give them a fair test before switching to Kadee. I'm not going to go out and buy a set just to try them out, though. I've been extremely happy with what I've got.

I'll say one thing positive about the cheap knuckle couplers: They are a 1000 time improvement upon the nasty horn-hooks. Horn-hooks should be banned from interchange traffic!




On an unrelated note, I'd like to thank the spammers for stress testing my blog software. I must say, 800 comments is WAY too many to display on one page. You'd get tired of reading long before you got to the last one.



Walthers GP9 Wheel Cleaning

Yesterday, I picked up a Walthers GP9M locomotive in the Wisconsin Central scheme. When I placed it on the layout and turned on the power, nothing happened. So, I gave it a gentle nudge to make sure it wasn't on a section of dirty track. Still nothing.

Immediately I suspected dirty wheels, and took a look at them. They were black, like someone had tried to use a "darkening" solution on the wheels.

So, in order to get this locomotive to run, I was going to have to clean the wheels. First, I connected a 9V battery to the motor terminals to get the wheels to turn. Then, I used a paper towel with cleaning solution to remove the topmost layer of gunk. That helped a little bit, the locomotive would at least move a little.

Next, I tried a dremel tool with polishing bit. Using the white buffing compound, I cleaned more of the gunk off the wheels. After 30 seconds or so, I had to stop and clean off the polishing bit. This usually works for the heavier cases of crud and dirt, and it did work here, but not good enough. The locomotive would move back and forth at high speeds, with the headlight flickering the whole time.

Finally, I switched to the steel wire wheel attachment on the dremel. This removed the rest of the gunk, and got in to the most important places on the wheel: Near the flange. A model railroad wheel tends to pick up power from around the center of the wheel tread in to the flange, and that's the point where it needs to clean most. The wire wheel successfully cleaned off the rest of the gunk, and restored a shining appearance to the wheel treads. When I tested it on the layout this time, the locomotive would crawl at low speeds like the one I installed a decoder in.

I hope the steel wheel did not remove any electroplated protective covering on the wheels. If it did, there may be issues in the future with dirty wheels.

Update: I've found a better way to clean the wheels than using a metal wheel. It's the Dremel 423E cloth polishing wheel.


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