DCC in the Garden
Putting DCC in the garden does make things nice. No need to dig up your master piece to run a new wire for rail switch, block, or even building lighting control. You can even have signaling without a daunting amount of buried wire. And let us not forget about a world of sounds that only DCC can control.
This web site assumes you have decided to put DCC, in one form or another, into the garden. In its simplest form you need only run the track bus and feeders. No more complicated than a simple traditional setup, yet sound and complex locomotive lighting can be controlled.
For G scale locomotives with DCC decoders, see the main table of contents.
SUGGESTION #13-12: How to MU The LGB Unitah and Sumpter Valley Locomotives Without Changing Gears.
See Electronic Gearing Below. Just program the faster locomotive to run slower!
SUGGESTION #13-1: Soldering Bonds (Jumpers) to Code 332 Brass Using a Resistance Soldering Station
If you are not using stainless steel joiners, then you will need to install jumpers whether you use code 332 brass or code 250 nickel-silver. The only way to avoid jumpers is if you intend to feed every piece of track.
Read below on busses and feeders. Note how quickly wire appears to age. If I were building my garden railroad again, I would use #12 for feeders. I would also use #12 for mechanical strength. I had a mudslide. Using a typical garden shovel to clear the mud, I managed to break two of my bonds (jumpers.)
A resistance soldering system will use less solder— you are less likely to have blobs. The best part is avoiding the melting of ties.
Please read the section on soldering tips; particularly the part about a resistance soldering station. You will need every bit of 250W to do the job. A lower heat will require the long application of heat and melt ties. Use 18 AWG solid or stranded wire. You don't need anything larger in diameter (see below) and larger diameter wire required even more heat when I tried a fatter piece. I prefer solid for outdoor use as it will not corrode as quickly. If you use stranded, fully cover the piece with solder. You can use your regular soldering gun to do this. Before soldering, form the piece of wire like this:
You MUST lightly sand the rail before attempting to solder to it. Use a piece of sand paper or a foam-rubber block clad with fine sanding grit available from your favorite home improvement store.
I used regular electronic solder with rosin core flux. DO NOT use acid flux on anything electrical! I tried using killed acid liquid flux, but it didn't work any better than the rosin core solder.
Why don't you need a larger piece of wire? The all important thing to us is the voltage drop. When you are done, you will only have about 0.25" (6mm) of wire between your rails. Even at 10 amps, this will not be enough to require bigger wire. Feel free to try 16AWG solid wire or larger if you want to, but be careful not to melt your ties.
Note: Over time, I have adopted a much larger and more complex shaped bond. Do you need to worry about them being unsightly? In no time at all they corrode to a dark color. You definitely don't even notice they are there and will find them somewhat difficult to spot without conscientiously looking for them. So much so, that's why they are easy to hit and break!
INFORMATION #13-2: Measuring the Locked Rotor Stall Current of a Large Scale Locomotive
There are a few hazards involved in measuring the locked rotor stall current. Frequently, the motors of quality large scale locomotives are metal. These gears frequently have sharp edges. The motors have quite a bit of torque. So the first thing to be careful of is that you don't get your fingers sliced while trying to hold the motor shaft.
Another hazard is that you could burn up the expensive motor. I have your attention now, don't I? Stalled, these motors will draw many amps. Don't hold the motor shaft still for more than a second. Longer than that, you are taking your chances.
Lastly, stall current is often measured at 12V. But for large scale, it needs to be 16V to 18V. After all, the current the decoder will see will be due to these higher voltages. It's important to realize than many model train power packs drop output voltage when subjected to a high current load like when you have a stalled motor.
I don't have a power pack that can maintain 18V, or even 16V, and put out more than 3 amps. That is probably just as well, since I don't want to "let the smoke out" of an expensive motor. Fortunately, I can estimate the stall current at these higher voltages based on what I can measure at 12V. I will report the 12V reading for consistency as well as my estimates for the higher voltages. You should buy your large scale locomotive decoders based on these higher voltages.
How do you know if your power supply can supply enough power to measure the stall current? You need to have a volt meter hooked up to the power supply when you make the measurement. Suppose you want to measure the stall current at 16V. The volt meter needs to be able to read 16V WHILE YOU ARE HOLDING THE MOTOR SHAFT STATIONARY. If it drops, that isn't measuring the stall current at 16V. If you are using a train power pack, turn it up. If you can never get it to read 16V, then the power pack isn't powerful enough.
Be extremely careful when attempting to measure the stall current of an S, O, and especially G scale motor. For one thing, the high quality brass gears may be sharp enough to cut. For another, they are strong enough to break a motor or gear mount. I know this from experience!
For locomotives with 2 motors, I will indicate that 2 motors are involved and that you will need a decoder that is rated for this double high current. If my experience with the new Bachmann Shay is any indication, you will probably always need to buy a 6A or 8A decoder. In this case, if you can't buy a 8A peak rated decoder, don't lose any sleep over it. I may be premature in saying this, but I doubt any load this locomotive will see will ever get it close to stalling.
For more information on measuring the locked rotor stall current of a locomotive, see the section on Wiring Tips for Specific Locomotives.
SUGGESTION #13-4: How Far Apart to Place Feeders.
12' (4m) is a good rule. This is especially true if you are not using the stainless steel clamps, or are using 18 AWG wire or larger for jumpers. You have to be careful that during a heavy short, your jumpers don't get hot. You do want this to be a trouble-free railroad, right?
18' (6m) would be the limit if using 14 AWG jumpers or stainless steel clamps. At the longer distance, the voltage drop across the rail might be noticeable to some.
Longer distances you have to worry about the voltage drop and the quality of the joints. With a garden railroad, who wants to be digging up feeder buses to add more feeders? Or fix joints that have broken or corroded?
I use jumpers and a feeder for every 6' (2m) of track. I call this extra effort "insurance". It's not necessary. It's just what I choose to do. I use 14 AWG solid for feeders because I have a box of it.
SUGGESTION #13-5: What Size and Type Wire to Use For Feeder Buses.
I suggest you use at least 12 AWG wire. I use 10 AWG solid. This is a good idea if you have very long runs. In my case, I have pieces over a 100 feet (33m) long.
What type of wire is a good question. There are wires designed for direct burial but they are not suitable for garden railroad use.
Underground sprinkler wire: Solid wire, but much too small in diameter to carry the necessary currents.
Low voltage lighting wire: Normally, this stranded wire has its termination inside above ground lights. Stripping stranded wire and then trying to solder buried feeders to it will ultimately fail - probably even if you succeed in waterproofing the connection. Part of the problem is that soldering stranded wire makes it very rigid and the tiny flexible strands can break off. If you walk on your track, you are aggravating this problem. If you don't successfully waterproof the connection, you are certainly doomed to failure.
Buriable "Romex:" This wire, available in the United States, has a jacket that makes the wire buriable. Cutting into this jacket and burying it nullifies the jacket's benefit.
Until I find a wire that seems really good, I use heavy solid wire. The fatter the wire, the longer it will be before it corrodes through. I can't tell you how many years, but #10 solid should give you plenty of them. What I can tell you is if you saw how cruddy my wires look after just a few years in the ground, you would use #10 for everything! I still expect years of good service. What's appalling is how quickly nature makes them look so old after such a short time. It definitely drives you to want to be as sure as you can that they will be there a long time.
While all the feeder connections challenge garden wiring, properly installed trackwork helps you out. If you put several inches of stone under your track and your feeder connections are in the middle of the stone, your connections will not be immersed in constantly wet soil.
Another thing that you should think about is the wire's mechanical strength. In short, the thicker it is, the sooner you will know you hit it before you break it accidentally sometime down the road.
SUGGESTION #13-7: What Size Wire to Use For Feeders.
I suggest you use at least 16 AWG. If you run feeders to your track every 6', you can use 18 AWG. I use 14 AWG solid. If I were to do it again, I would use #12.
Another thing that you should think about is the wire's mechanical strength. In short, the thicker it is, the sooner you will know you hit it before you break it accidentally sometime down the road. If you should have a mud slide or something else that covers the track, you may not see it and may break it before you know it. I haven't broken a feeder, but I have broken a bond (jumper.)
SUGGESTION #13-9: Insulating Feeder Connections.
If you have your track on top of several inches of stone, keeping the wire away from wet soil, you won't have a huge problem with shorts taking place through the ground while operating your trains on dry days. However insulating will help prevent water from corroding the connection.
Use liquid electrical tape or liquid vinyl instead of heat shrinkable tubing. No matter how tightly you shrink on the tubing, capillary action almost assures water will find its way in. Both the liquid tape and vinyl are available at your favorite home improvement store, electrical supply store, or well stocked hardware store. The vinyl is a little thicker, but feel free to apply multiple coats of either.
If you walk on your track, no matter what you use, the stones will cut through the wiring insulation in time.
Note: While this page is on wiring, I'll tell you how I like to install my garden track. I use bricks into which I install masonry anchors about every 1.5 - 2 feet. A good hammer drill or impact drill can drill through these bricks like they are wood. I shim the bricks using various sizes of stone finished with crushed marble "sand" called paver base. I now have fairly rigid points anchoring the track. After connecting the feeders, I fill up the track with ballast. I put all this on top of landscaping fabric to keep the dirt out of my stone work. If my track is way above the ground, everything looks like a fill. If I want my track to be the typical few feet above the surrounding ground, I dig a trench and put all this stuff in it.
SUGGESTION #13-6: DCC and Live Steam Coexisting on the Same Garden Railway.
If you have a live steam locomotive, lay awake nights dreaming of Asters, want friends to be able to bring theirs over, or might own one some day, a little thought now may be required. You basically have two things to think about.
1) Will you try to run DCC equipped locomotives while running one
or more live steam locomotives?
Your live steam locomotive's wheels probably short the two rails together. Let's look at these situations.
First, what you can't do or do practically:
Forget trying to MU a DCC locomotive with a live steam locomotive. Most of us aren't coordinated enough to operate two different kinds of controls at once. I'm definitely not!
Unless you insulate the wheels on your live steamer, you can forget running a DCC locomotive and a live steamer in the same electrical block. You could have a series of switches to sequentially remove power from the block the live steamer is in. Too much trouble, too much coordination required, not enough fun.
If you don't have two separate loops, forget it!
Now here's what you can do practically:
If you have two or more loops, and use one for live steam and won't wire it, you have what is called a no-brainer.
If you have two or more loops and want to run you live steam or DCC or either loop, you can:
1) Use a booster on each loop and turn off the unused booster. Yes, you theoretically could leave the booster on and let its short circuit protection keep it shut down. I don't advocate this latter approach. I don't know if sustained shorts over long periods of time could ultimately damage the booster. You don't want to find out the hard way!
2) Use a switch to disconnect the loop that is running the live steam locomotive.
Now here is a interesting problem. What if you use DCC to control rail switches? If the rail switch is running off of the booster the live steamer is on, you have a problem. Not necessarily a big problem; as long as you think about it now. This situation is likely to crop up if run your trains into the garage for storage. You can:
1) Forget DCC controlled rail switches. Use manual. Again, a no-brainer.
2) Run a separate bus for controlling rail switches. You will need a separate booster. You can buy a standard booster of about 5 amps or less for this purpose. You don't need the 8-10 amp boosters you may be using for your garden locomotives.
3a) Use a switch to select which one of your loop boosters supplies the rail switch power.
3b) Use a relay powered by one of the boosters. If a short occurs on one booster, relay switches to obtain rail switch control power from another booster.
Choices 1, 2, and 3a are easy. 3b has the advantages of using a separate booster without the cost of buying it. This is the approach I use.
SUGGESTION #13-14: DCC Control of Master Turnout Power
This is similar to above and is what is implemented on my garden railway. It serves several functions.
1. Turns power off on the turnouts when I will
kill the power to the track. This was the primary purpose.
SUGGESTION #13-7: Probably Best to Avoid Aluminum.
Aluminum track can easily develop insulating layers of oxide in the joiners. You will have to use clamps as you cannot solder to aluminum. Note: This suggestion is given because you are considering DCC. That is why you are reading this, right? This suggestion applies to regular DC track power as well. Of course, if you are going battery operated, you can use aluminum rail.
SUGGESTION 13-8: Use LGB 24V Light Bulbs for your G scale locomotives.
Many G scale locomotives use voltage regulators and low voltage lamps so they achieve full brightness before the locomotive is moving much. For example, LGB uses 5V lamps and regulators and Bachmann uses about 8V.
With DCC, you don't need the voltage regulators. Keeping them means you spending a lot of time figuring out exactly how it is hooked up and works. You also may not be able to take advantage of all that DCC has to offer if you keep the voltage regulator.
Toss the voltage regulator and the low voltage lamps that came with your locomotive. Just use the LGB 24V lamps with your DCC decoder. It's that simple! In case you didn't know it, DCC puts a constant voltage on the track that makes the 24V lamp appropriate.
The LGB part number is 68513.
For G scale locomotives, I would suggest that you use a 5A decoder in any two motor locomotive and a 3A decoder in any single motor locomotive. Decoders should be given as much space as possible inside a boiler and preferably access to outside air for cooling. The later is a good objective that you can rarely fullfil. My real problem isn't the internally generated heat as much as Texas' 105 degree days. Still, my Sumpter Valley, with its Digitrax DG580 decoder, ran 1.5 hours before thermally shutting down.
I have three loops on my garden railroad. One has an intentional 7.8% grade for the logging loop. For this steep grade, load compensating decoders are a must if you have a back yard full of guests and you don't want to have ride the throttle to get it up the hill and to keep it from rocketing off a curve coming down.
My Sumpter Valley, on my 3.8% grades of the non logging loops, shows a noticeable, but not significant, speed change with its non load compensating decoder. If your steepest grade is about this much or less, you may be able to get by without a load compensating decoder. A smaller locomotive, like an LGB Mogul, has to work harder to get up the 3.8% grade and will therefore go down that grade faster without load compensation. So, though not essential for a smaller locomotive, you probably should consider buying a load compensating decoder. Unless you have tight downhill curves, you should not have a runaway rocket situation. All lesser grades, you don't need to buy a load compensating decoder. There is no harm, of course, in outfitting all locomotives with load compensating decoders as I am doing.
See the information below on selecting decoders with load compensation if this interests you.
INFORMATION 13-9: Decoders with "Back EMF", "Feedback", "Load Compensation", Speed Stabilization"
"Back EMF", "feedback", "load compensation", and "speed stabilization" are names for the capability of decoders that can keep the speed of a train relatively constant automatically while ascending or descending a grade. When I have a back yard full of guests, I have found this to be a useful feature to have as I cannot concentrate on watching the trains. This feature can be turned off when more prototypical operation is desired.
There are only a few manufacturers that have decoders for G-scale locomotives.
Lenz's has a maximum output of 3.5A and does not support 128 speed steps. It handles long addressing. It has no special effects. As of this writing, Lenz has a special dual decoder combination that has load compensation for use with two motor locomotives. However, this pair costs as much as two decoders.
Zimo's has a maximum output of 5A, supports 128 support steps, long addressing, and has no special effects useful to a US modelers. The MX65 comes in three models, the most advanced of which includes a 1.2V voltage source and a programmable output for controlling sound systems that use voltage control of their sound effects.
All the MX65's have a computer ribbon cable connector for the lighting and function outputs. A screw terminal block is used for track and motor power. You must be careful stripping ribbon cable wires. Unfortunately, the ribbon cable connector does not come with the decoder. You can get these from Digikey. See the section on Parts for part numbers.
Until Digitrax comes out with a G-scale decoder with back emf control (load compensation, speed stabilization, feedback or whatever a manufacturer wants to call it), I prefer the Zimo decoders. They can be ordered from The Train Connection. See the section on Wiring Specific Locomotives for more on the Zimo decoder. I have had the misfortune of having a high infant mortality rate - electronics that fail within the first few hours of use - with the Zimo's. Fortunately, Carroll at the Train Connection has always been quick to make good on them.
SUGGESTION 13-10: Using Soundtraxx Sierra Sound Modules with DCC Decoders
The Sierra has a few features that make it most desirable in a DCC G-scale locomotive. Besides the best possible sounding bell, even over their conventional great sounding Soundtraxx product line, the Sierra offers a number of features that are particularly useful to the garden railroader. These include magnet triggered bell and grade crossing whistle, as well as voltage controlled two toots for forward, three for reverse, and one for stop.
There is an error on the Soundtraxx website concerning the bell, whistle, hiss, and coupler-clank when hooked to a DCC decoder. You will notice that the screw numbers don't match their documentation for the Sierra when used in a conventional DC locomotive.
The Sierra has a feature that detects that your train is in motion, which way it is going, and when it is stopped. You connect the Sierra's sense lines to the motor wires from the decoder. To prevent electrical noise from your DCC decoder from getting into the Sierra, you will need a filter consisting of the inductor (coil) and the capacitors shown. Note that when you stop your DCC locomotive and leave it idle for some time, the Sierra will eventually shut itself down.
If you do not have a chuff sync mechanism on your locomotive, you could use another hall-effect sensor and a wheel mounted magnet. Or you Sierra can generate a chuff based on motor voltage. This uses the same sense lines that trigger the whistle.
To make the chuff sound more "interesting" in the garden, I discovered that a chuff rate that is about half of what it really should be is more entertaining. For a standard, non-articulated locomotive, there should be four chuffs per revolution. In the garden, I only use two. Whereas my HO layout is for prototypical operation, my garden railroad is for entertainment. This is just something to think about. You don't need to set the chuff rate at precisely half. I just run the locomotive at what I intend to be its normal operating speed and then adjust the chuff to suit me.
See the Generic G Decoder and Sierra Sound Installation in Locomotives section.
SUGGESTION 13-15: Del-Aire for Turnout Control?
LGB switchmachines do not hold up well outside. They are not designed to be water resistant or to keep out dirt. They are too weak and don't have enough throw for non-LGB turnouts. After about four months, it became clear that I would keep buying LGB's great locomotives but another solution was needed for turnout control.
I installed Del-Aire "air motors" (actually air cylinders) using the Llagas Creek G-scale mount. They work like a charm. The vinyl tubing supplied by Del-Aire is not tolerant of sunlight, so I found a way to use drip irrigation tubing available in the sprinkler section of your favorite home improvement store. To use drip irrigation tubing with your air motors, buy four sizes of brass tubing from your local hobby shop.
Get sizes 3/32 (#126), 1/8 (#127), 5/32 (#128), and 3/16 (#129). Cut about 1" long piece of the 3/16. Cut the next size about 1/4-1/2" longer. The next smaller size another 1/4 -1/2". The smallest size should be cut about an 1" longer still. So the smallest size is about 3" long. Wipe each down with liquid flux and then use a 200W soldering gun and solder one inside the other. Make sure the solder goes all the way around. When done, cut the whole thing in half and you will have two Del-Aire to drip irrigation tubing adapters. DO NOT solder the cut end! Solder will likely plug the smallest tubing. Take it from someone who learned this was a bad idea the hard way!
You will need to glue the tubing to this adapter. This adapter you just created has no barbs on it. When it gets warm, the tubing softens and the air pressure will blow off either hose. Walther's Goo works. Make sure it cures thoroughly before applying air or it may blow off again.
I then cover the Del-Aire tubing with heat shrink tubing. DO NOT shrink it! I put a big piece of heat shrink over the whole thing, including the brass tubes and the drip irrigation. This I shrink lightly, but avoid going tight around the small tubing because it will easily melt. That's it!
The only drawback in using DCC to control Del-Aire, is that you will find their electrically operated pneumatic solenoids to be expensive. (In the industrial automation world, they are actually reasonably priced.) If you control your Del-Aire air motors with a manual control, Del-Aire is extremely reasonably priced and MUCH cheaper than LGB or anything else.
Use the following tubing sizes:
SUGGESTION 13-16: Sound Triggering
There are many ways to trigger sound.
1. LGB: The easiest. If only LGB needed our money. They refuse to sell even LGB owners the bell and whistle trigger mechanism who own older LGB locomotives that didn't have sound.
2. Reed switches, while very delicate, seem to be the most sensitive. Fortunately, the ones uses for your home alarm system are purchasable from Radio Shack. The home alarm system ones are in a plastic housing to protect the switch. They come in a variety of styles and you will find at one time or another, you will need them all. They come as two basic types.
Most are a long barrel. Use a piece of 1x2 lumber cut to fit under your tender and hold the barrel pointing at the track. Space for the LGB magnet triggers.
The other general type lays parallel to the track and you can glue to the bottom of a truck. This is especially useful for tenders that don't have extra space for a 1x2.
You may encounter one problem with the sensors that are related to your speaker. If you use a big speaker with a strong magnet, the magnet in the speaker may interfere with the sensors. I like my big speaker and found mounting the sensors close to the front of the tender got them far enough away.
SUGGESTION 13-17: Motorboating / Speaker Sounding Like a Motorboat
Does your sound system sound more like a motorboat than a train? Did you use a big speaker? Is it a 4 ohm speaker?
Most sound systems are intended for use with 8ohm speakers. If you found a nice, big speaker with a healthy magnet on it, it may be a four ohm speaker. If it is, this is your problem. You are overloading the output of the audio amplifier.
You have two choices. The obvious is to use a 8ohm speaker. However, many 8 ohm speakers have very small magnets, are very inefficient, and don't cover much of the audio range.
Luckily, you can still use your 4ohm speaker and get most of the advantages. Just put a 4 ohm, 1/2 watt resistor in series with it. This will bring it up to 8 ohms. Perhaps easier to buy, is two 1/4 or 1/2 watt, 10 ohm resistors. Put them in parallel with each other. That makes 5 ohms. Put this pair of resistors in series with the 4 ohm speaker. The total is 9 ohms. That's good. Yes, this will cut the amount of power going to the speaker significantly compared to a normal 8 ohm speaker. But if the efficiency of the 4 ohm is better than that of a tiny magnet 8 ohm speaker, you are still ahead. Bottom line, if you find that the locomotive is too loud and you have to turn it down, who cares if there is an efficiency loss due to this extra resistors. This is what I have found to be the case.
SUGGESTION 13-18: Sensor Bracket for Bell and Whistle Triggers.
Until LGB realizes the goldmine they are giving to Radio Shack, Radio Shack will continue raking in the bucks selling us door alarm sensors for triggering bell and whistle effects when adding sound to locomotives; including LGB locomotives. Here is just one way you can mount the skinny cylinder type Radio Shack sells. The cylinder will just fit into the hole indicated. It will be barely snug enough to hold itself in. A little Walther's Goo can be used to hold the sensor permanently in place. The spacing of the sensors is for the spacing of the LGB magnets — which they will sell you.
The block of wood is actually used upside down from that shown. But this is how it will look when you mount it on an upside tender!
The length of the block of wood is not critical. Neither is the spacing of the holes for the sensors. The groove for the wires is certainly not critical. I just cut these on my radial arm saw.
Be sure to use safe work practices when using a radial arm saw! This is the greatest tool ever devised by man for removing fingers next to the sheer. Be very careful. I suggest you make several of these wooden blocks at once leaving the long piece of wood to hold onto and then cut them to their 1-3/4 length. Use a pusher stick when working on the small pieces. Definitely wear goggles to avoid being hit in the eyes with these small pieces of wood. If you are using a radial arm saw, you are responsible for knowing how to use it safely. I do not pretend to be an expert in the use of radial arm saws. This website is therefore not a substitute for you knowing how to use this dangerous tool safely. Read your owner's manual.
The block of wood is a 1x1-1/2 cut in half. Why cut it in half? Why not just use a 1-3/4 piece of wood? If you don't have a long tender, you will find a whole piece of wood may hit your wheels.
Funny, after you buy your first LGB locomotive or two, you may find you need more magnets. After you have acquired a few more LGB locomotives with sounds, you now find you have enough extra magnets to play see-who-can-get-the-magnet-in-the-gondola-as-it-goes-buy. No, I haven't been that bored yet, but I do have plenty of magnets!
When done, Walther's Goo the block of wood to the bottom of your tender with the sensors facing downward. Be as close to the truck as possible. Note, magnets on curves, particularly tight curves, will not be sensed in all cases. This is why the truck-mounted LGB bell and whistle trigger sensor is the ideal choice.
I do not suggest mounting this block of wood directly under your speaker if you are using a quality, large magnet, speaker as I like to do. Large magnets on such speakers will interfere with operation of these magnetic sensors. Hence, my suggestion that you mount it in front of the front truck if you have problems under the middle of the tender. Test the sensor operation with track-mounted magnets and an ohm meter.
Note: Radio Shack sells a flush mount sensor that uses double-sided foam tape that you can mount on a truck. I've recently tried that. The truck doesn't have a big mounting surface for it to stick to. I'm concerned they may not stay mounted without extra glue or something else. Until I know for sure, you may be on your own. I had to use these on my Bachmann American which had a tender too short for this block of wood approach. I'll find out if there is a problem or not and what the solution is. If you already have encountered problems with them coming off and found a solution, write me and I'll give you credit!
SUGGESTION 13-19: Locomotive Cooling.
If you are into diesels, you are in luck. You could use a muffin fan, for a PC, purchasable at Radio Shack, to circulate air inside your diesel. If you need a 12VDC circuit, use the power supply circuit I use for the Sierra sound system. See the locomotive installation notes on the generic decoder with Sierra sound.
Those of us in Texas with steam locomotives have a serious problem. I have found even the huge lead weight, on our 100+ summer days, won't keep a decoder out of thermal overload unless the humidity is very low (I had locos running at 106 degrees F with 27% humidity. At 47% humidity SOME decoders would not work). I'd love to mount the decoder under the locomotive, or even the tender, but there is never room. I hate running so many wires from the tender.
While this sounds horrible, I now mount my decoders in the cab. Yes you can see them. Yes there are wires. No doubt, this is not as pretty as hiding the decoder somewhere. But to be perfectly honest, I don't think anyone has ever noticed. No modeler has ever asked me about it. I don't even notice it! Even for me, who is not in awe when I step into my backyard because I see it everyday, I have too much to keep an eye on to notice.
Another choice is to place a switch in a locomotive that allows it to run on DCC or DC. If the electronics overheats, you can switch from DCC to DC. You need to do two things. One, is place a switch in each locomotive that selects the output of a decoder or directly to the wheels. Then you need a DC power source and place a switch that selects the DC power supply or the output of a DCC booster. Here is an example of a locomotive I have wired this way: LGB F-7A.
SUGGESTION 13-20: Electronic Gearing — For Locomotives with More Than One Motor or Two Different Locomotives.
I hear that the Sumpter Valley and the Unitah run at different speeds. Some people want to double-head them. Here is how to do it.
I recently had a problem with my Sumpter Valley — an articulated locomotive with a motor driving each engine (powered truck) separately. One of the motors, due to age, started running slower than the other. I found out from the manufacturer that this was not uncommon.
Lesson #1: All locomotives with more than one motor should be placed on a test stand periodically to check for speed differences. In my case, I didn't know it until it was too late and I stripped some gears.
The manufacturer recommended I replace both motors at the same time. That's not an inexpensive solution! And how soon will I need to replace both motors again?
Enter a technique from my factory automation days. It's called electronic
gearing. This is a process where multiple computer controlled motors
run at different speeds, but proportionally to each other in some
way. Maybe one always turns 90% slower than another. This would be
useful in conveyor control or maybe newsprint going through presses.
It can be easily simulated in DCC using two decoders.
SUGGESTION 13-21: Virtues of DCC.
I hear true DCC wireless is coming. This is where the DCC signal is radio'ed directly to the locomotive and the locomotive is running on batteries. In Texas, keeping the track clean is easy with an old drywall sponge. So I don't need true wireless. Maybe you don't either. Be on the lookout for it if you do.
I use standard DCC wireless where the radio signal goes to a receiver. Commands are then put on the track as in standard DCC. This works fine for me. Why should you consider it? You can walk your backyard amongst your guests. You can control trains and throw turnouts even when the backyard is crowded.
Yes, you can even DCC control your turnouts. This is not inexpensive, but in a crowded backyard, this is a priceless capability. (I use DCC to control air valves. I use air powered turnouts. They hold up to the weather and have more force than the typical outdoor turnout motor.)
This is a feature of some command stations, like the Digitrax Chief, and/or some stationary address controllers. This is a feature few modelers employ, but I find particularly useful outdoors and does not require the use of a computer.
In the dark ages before DCC and twin-coil switch machines, modelers made something called a diode matrix to control their yard ladders. DCC has routing. It works without any additional hardware, being all done in software in either the command station, stationary address decoders, or a computer if you wish. Using it does not require you to be a programmer and it can be used for other things besides yards.
I find it particularly useful in the garden because I cannot see all my turnouts from one place. With wireless and the freedom it affords, I don't want a control panel.
Routing throws multiple turnouts when I throw a particular turnout. Just because it throws a turnout one way due to another turnout being thrown, doesn't mean that same turnout has to be thrown back. The two are not hard locked together. They work together only when I want them to. Here's a perfect example:
I have a wye in my garden where I can only see one turnout at a time. Only in one instance can I see two. Routing allows me to ensure that the two corresponding legs of the wye are thrown by only throwing one of them.
When I say they are not hard locked together, here's how I use it. I have a turnout leaving my garage. The other two turnouts are on the mainline. When I throw either turnout out on the mainline towards the garage, the one for the garage responds accordingly. However, when I throw either out on the mainline back to the mainline, the one at the garage does nothing.
I also have a five track yard in my garage to store my trains. That takes four turnouts. I only need throw the turnout for the final storage track that I want and the appropriate turnouts that need to move to align for that track do so.
SUGGESTION 13-22: Watertight Heat Shrink Tubing.
J. Reep wrote me and told me the following about a heat shrink that would seal out water:
"I noticed on your website you mentioned that heat shrink did not seal to the wire and water would by capillary action enter the splice.
I have been using the 3M EPS-200 adhesive lined flexible polyolefin (heat shrink tubing). This tubing has an adhesive that melts and seals the tubing during the heating process.
I have been purchasing the tubing from Allied Electronics in Fort Worth, Texas 817-595-6455. They do handle mail orders.
This is the part numbers for Allied Electronics.
Hang onto your wallet, the heat shrink is not cheap. If I remember correctly it was about $15 per package."
SUGGESTION 13-23: Using Non-DCC Lighted Cars on DCC
This will generally work well. If you have good, clean track and good pick-ups, it will work very well; perhaps better than when using DC because the track voltage does not vary! The only thing you need to watch is the car can withstand your DCC track voltage. I run my track voltage 18V.
USA Trains™ makes a lighted caboose with a flasher on it. I have contacted them. This caboose is good for 22V.
Call manufacturers before using a car with electronics in them! The flasher in this caboose obviously has some electronics in it. A plain lighted car might have some electronics in it. Inexpensive ones may not, but the more expensive models may to make the lighting a little more consistent as the track voltage varies. (Remember, the car was designed for regular DC usage.) So if you have any doubt, contact the manufacturer. You could blow the electronics in the car. Those with just a light bulb, will only blow the bulb.
SUGGESTION 13-24: Programming LGB MTS Decoders
LGB is now supplying some of their locomotives with MTS decoders. For the most part, they work on DCC layouts. You cannot program them with Digitrax equipment in any of the programming modes. It may work with other manufacturers. Try it. The worst that will happen is that you will completely screw up the CV's in it! (Okay, that isn't funny. I didn't manage to alter the programming with the Digitrax system, but the loco would not work. I did manage to get it back.)
As of this writing, you are limited to 23 addresses. It comes preset to address 03. I suggest if you do not have an MTS-equipped locomotive yet, that you not assign these low addresses to any more locomotives in the meantime.
Assuming you have Digitrax or some other manufacturers DCC equipment, how do you use an LGB MTS decoder? There are two things.
1. Buy an LGB 55045 programmer. Hook it to a computer serial port,
a AC or DC output power supply (the ones I use for my DCC boosters
worked fine), and attach the programmer to some sort of programming
track or engine test stand. The 55045 is the least expensive way to
program the MTS decoder.
My MTS decoder is a 14 step unit. You have to have a DCC system that you can set to 14 steps. For Digitrax, it can generate 14 step commands for specific addresses. You do not have to run your entire system on 14 steps nor reprogram all you other decoders. I'm sure you are happy about that!
I have never had to run a decoder at 14 steps before. With the Digitrax system, I just had to read a page in the manual I passed over years ago. "Status Editing," as Digitrax calls it, is easy on the Chief. Best of all, the Chief remembers that you set a specific address to 14 steps even when the Chief is turned off. So I have only had to do this once.
If you have not used 14 steps before, you are in for a surprise. Don't give the throttle a quick twist of the wrist like you may be doing now. You may go through those 14 steps in a hurry! The locomotive will leap to life. When you go to stop the locomotive, keep this in mind. Turn the throttle down slowly or else it may abruptly stop.
You will not be able to control the sound with the normal DCC function buttons. It makes plenty of sounds and triggers from track magnets. For me, that is fine. With a backyard full of guests, I don't use the DCC function buttons on my locomotives that are capable of doing so.
Additional Impressions of the MTS:
It does have some good features. It has load compensation. The sound that came with mine is good. Sound is not necessarily a function of MTS, but I expect all MTS-equipped locomotives will have sound. Of the four manufacturers of decoders I am running, this one has never shutdown in our Texas heat.
BONUS: Wooden Ties for G Scale
Here is a bonus topic. It's non-DCC. While I am figuring things out, you might as well benefit from it.
Should you decide that you want to lay your own track, you may want to make your own ties. You may be wondering if it is worth your while to make them yourself. I can make 450 in 75 minutes at a cost of about a nickel each. This is about half-price compared to commercial ties. I make mine oversize. If you make them smaller, your cost will be lower.
I talked with a G-scale bridge builder. He recommends mahogany. It isn't the hardest wood available, but as it turns out, harder woods don't take preservatives well and therefore deteriorate faster.
I make my ties slightly oversized. Mine are 7/16" x 7/16" x 3.5". This is very close to the prototypical 9" wide. Prototypical ties are 6" thick. It is convenient to make them square. When ballasted, who knows how thick they are. When they are not ballasted, they make good bridge ties. Also, the thicker ties makes them a little more tolerant of being walked on — which is how I service my hard to reach tracks.
Buying hardwoods is a bit different than typical "dimensional" lumber from your favorite home improvement store. First, wood is sold in thicknesses usually from 1" thick to 2" thick in increments of a quarter-inch. But don't show your ignorance by asking for 1" thick. Ask for "4 4" or "4 quarter." 1.25" thick is called "5 4" which is five quarters of an inch thick.
Hardwoods come in seemingly random widths and lengths. Also, one of the edges may not be straight. How do you know what it cost? Hardwoods are sold in "board feet" which is one square foot at an inch thick. Luckily, you are not trying to build fine furniture. Find a piece about 4-6' long, 6-8" wide, and "4 4" thick (to make 7/16" ties) for your first project. If you want to make ties of a different thickness, you may want a different thickness board to minimize your waste.
You will also notice that the wood comes with finished sides and coarse sides. The finished surface wood does cost more. It will still make ties for a nickel. Buy the finished or the rough surface. After sawing up the wood, I just put the rough surface down.
Set up your table and/or radial saw and make a pile of sawdust!
I'm not an expert on stains or preservatives. Here is what I have figured out. What is now generally sold as stain/preservative is a form of latex paint. This wasn't what I wanted sitting on the ground. I wanted something that penetrated. Now your choice is uncolored linseed oil or a Sherwin-Williams product called "Cuprinol"; which is available in colors. You can paint this stuff on or soak the ties in it. If you soak the ties for weeks, they may not take the color. I have a feeling that soaking them for a day or two is just as good. If you want the color, try brush applying the color after you have soaked them. When brushed on without any soaking, Cuprinol tries relatively fast. But when the ties are soaked for weeks, it takes the better part of two months for the ties to dry. The ties are somewhat sticky when you do this. As of this writing, Cuprinol seems to be doing a decent job for its intended purpose.
Here is one last tip. When buying the wood, if you see a piece of wood with a defect, like a split, you just might want to buy it. A split renders a good bit of the wood useless for furniture, but a split piece I bought only ruined about eight ties. They discounted the piece of wood I bought by a whole board foot - a discount of $6.32. I essentially got about $6 worth of free ties — almost 100 of them! Don't expect them to give you the entire piece of wood. Furniture makers are adept in their woodworking skills. They would expect a furniture maker to cut off the defect and use the rest of the wood.
INFORMATION: Lightning Protection
I used to wonder if I worried too much in worrying about my garden railway being hit by lightning. An article in Garden Railways is proof that garden railways can and do get hit by lightning. See Tom Ruddell, When lightning strikes, Garden Railways, June, 2004.
The best thing that you can do is disconnect the wiring from coming into your home and have a removable section of track as the article suggests. You should also unplug your television, stereo, and computer. If you are like me, you are too lazy to do all this. Or maybe your railroad is already built and disconnecting the wiring and making a removable section would be difficult.
If you are trusting your computer to a surge protector, you can do the same for your garden railroad. Like the surge suppressor on your computer, a surge suppressor doesn't guarantee protection. Lightning is a powerful force that is hard to control. The closer the lightning strike to your home, the more likely you will suffer damage. While surge suppressors are not a sure thing, they do offer substantial protection to all but the very close lightning strikes. Surge suppressors are inexpensive at about $0.75 each.
First, start with plugging your DCC equipment into a surge protector just like you do your computer.
Go to the section on parts and select a surge suppressor. I suggest the 27V unit if your garden railroad track voltage is 24V or less.
You will need three surge suppressors (actually called metal-oxide varistors or MOVs) for each set of rails running from your home to your garden and three surge suppressors for each set of bus wires.
A lot of heat will be generated for a close lightning strike. So the best thing you can do is bolt the MOVs in place using screw terminals. If you solder your MOVs to the ground wire, make sure the MOV lead is wrapped around the ground wire very securely before soldering.
I use #10 AWG solid wire for a ground wire. Use at least #14 AWG. Your ground wire should be as straight as practical and as short as possible leading to your ground rod. The ground rod for my home's electrical box was only a few feet from the door where my track and bus wires enter the garage. If your ground rod is not within a few feet, you can buy a ground rod at your favorite home improvement store for a few dollars. You will also need a clamp that holds the ground wire to the ground rod.
Ideally, your ground rod should only see a resistance of 20 ohms. But you can't measure this by attaching your ohm meter to the ground rod and sticking the other probe in the dirt. Unless you want to build a network of ground stakes in your yard, there isn't much you can do. If you have a house with a basement, you can help your situation by not having your ground rod against the foundation of your house.
Just remember that lightning protection is often not a sure thing; especially if you choose not to disconnect your garden railroad from entering your home.
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