Could someone explain a few things to me?


C

ChuggaChugga

New Member
Thanks for reading this. I've only made a couple of posts so far and I'm about as new to the hobby as it gets.

I've started my research into the hobby mainly by browsing online retailers and looking at the various types of equipment - everything from locomotives to grass and weeds. I also bought a model railroading magazine at a local book store, but most of the discussions in that are still a little over my head. So here are a few questions that I can't seem to figure out on my own! Thanks again for taking the time to offer help/advice.

1. What is DCC stand for -- and what the heck is it? What does DCC ready mean? I believe it has something to do with the "under the hood" function of the locomotives or track. When I was a kid and I played a couple of times with my grandfathers train set, his steam locomotive only did two things -- move forward, and move back. It was made probably in the 1950s, so it had no sound or smoke effects, of course. Now I've noticed that locomotives are getting more and more realistic, if you're willing to drop the $$$ to buy them.

2. Also going back to my Grandpa's train set - the track he had was in small sectional pieces, with no single piece being much longer than 8" or so (HO scale). Each piece had to be joined together, which wasn't a very easy thing to do - if you didn't join them together gently, and just right, you could risk bending a piece of the track and then it would be useless unless you very carefully bent it back. Now it seems like most of the more serious hobbyists make their own track by buying long sections of rail wire. I really like this idea for a lot of reasons, and I think that this is the way I'd want to go. What do I need to know about rail wire? Are there different sizes/shapes for HO? What about different metals? And when you make your own track, do you have to install each individual railroad tie onto the track? That would be extremely tedious, I would think.

3. I think I'm narrowing down what era of railroading I'd want to model, at least to start with. I'm very drawn by 50's era Pennsylvania freight trains and their associated mountainous landscapes. And based on my research of the PRR (thanks, Wikipedia) it seems like the 50's was a time when steam locomotives were still in use, but diesel was becoming the new standard -- which gives me the most flexibility with regard to which locomotive I'd want, since I could really go with either -- though I think I prefer the look of the early diesel engines. Any thoughts about this?

4. Finally - so far the best online site I've found for buying model railroading trains and supplies is www.modeltrainstuff.com. The only reason I say that I think it's the best is because the site is pretty well organized and they have lots of pictures - and both of those things are very important to me since I'm still trying to learn so much! Any other recommendations on good websites to browse?
 
Some quick answers:
1- DCC is Digital Command and Control. The older DC systems applied a varable voltage to the track for the engine to pick up and use. The higher the voltage to faster the engine goes. With DCC a constant voltage is applied to the track but it is a series of square waves that encode digital data. Each grouping of data is a command to an individual engine. In each DDC engine is a decoder (micro-processor and drive circuits) that convert the command to an engine speed or lights on/off etc.
Google "model train DCC" for lots more info.

2- Sounds like you are describing what is know as 'hand laying' track where the individual ties are glued down to the road bed the the rails are 'spiked' into place. While many of us do lay track this way it is not the most popular method. More common is using 3 foot lengths of "flex track". Again google the terms I put in quotes.

3- Yep, the 1950's is considered the 'transition era' since both steam and diesel were in use. It is also the most popular era to model for this reason.
Some of us like to keep all of the engines, cars, etc authentic to the era modeled but sometimes just run whatever we wish to have fun with.

4- I'm lucky to have a very good LHS with good prices so don't buy on-line for many items. What I buy on-line is the specilized items like old time car kits, decals and parts from small makers. Other here can suggest on-line sources.
I am aware of a few on-line stores that have excellent information. Here are some web site that have more info on the questions you asked:
http://www.nmra.org/beginner/
http://www.loystoys.com/
http://www.digitrax.com/
http://www.railwayeng.com/
http://www.handlaidtrack.com/
http://www.sierrawestscalemodels.com/
http://model-railroad-hobbyist.com/magazine/back-issues

Do look around on these sites and read the other info on how to do things.
Also do read though all of the threads on this (and other) forum(s). This will help answer your current and future questions.

Good luck and have fun.
 
O gauge Lionel and MTH trains run on three rail AC. HO has run on DC, or direct current on only two rails for donkey's years. Except in Germany and Europe where they use dots or something like a third rail.

DCC means a digital command control signal is used superimposed on a square wave AC current. A microchip in the locomotive reads the plus and minus cycles imparted by the base control unit and reads the time gaps between those 'hills' and 'valleys' to get information about what you want the locomotive to do. That's a very basic explanation...digital signal, ones and zeros, with the spikes and gaps in the current representing them.

The sectional pieces are fine, but they tend to have set curves in them which limits your configuration to whatever track plan those curves can provide. Also, the more metal joiners you use between those 8-9" lengths, the greater the chances of a loss of signal or current as corrosion and dirty, or just mechanical failure, creep in. With the 3' lengths of flex track, you have fewer joins, but also an infinite ability to make curves of any radius you want. Plus, you can cut those lengths down to a given size if you need to.

If you want to lay your own tracks, yes, you must find, or make, all the little ties, place them on your roadbed, hopefully nice and flat, otherwise the rails will dip and rise with them...it's hard on locomotives, and then spike the rail lengths over the ties, but keeping a mind to their spacing...or what we call the gauge.

The transition era between 1930 and 1959 is hugely favoured by modellers because it offers so much variety. If you constrain yourself to any one railroad, and many do, it does limit what you can run as you narrow the time frame. If, like many of us, you like locomotives and buildings from any railroads, you might want to freelance, or protolance (a bit of each) and give yourself some really unrealistic freedom. Remember, this is supposed to be fun. The more constraints you place on yourself, the more challenging and difficult it can be in terms of finding what you need. Most have to build what they need from scratch if they are truly modelling, or they buy expensive brass items.

To keep costs down, you must spend an hour here and there on general searches. M.B. Klein's, which is the site you mention, are excellent, but don't overlook trainworld.com, toytrainheaven, internetrains.com, discounttrainsonline, wholesaletrains, internethobbies, and about 20 others that you will well serve yourself to search for when looking for that rare or discounted item. Add ullrichmodels, dallasmodelworks, caboosehobbies, hogtrainz, empirenorthernhobbies, heck I could go on forever. Oh, mainlinehobby, firstplacehobbies...yup, I really could go on...and on....

Broadway Limited Imports has a website. They make very nice steamers. At their site, look in the left column for 'refurbished deals'. Sometimes they have desirable engines there for about 30% off. Their retail outlet, Factory Direct Trains, is a place with bargains all the time. Also, try Micro Mark, their HO train section. Geez, I gotta stop....I could go on...and on....
 
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Selector: I thought that DCC used pulsed DC current, meaning no negative spike in the power? I was under the impression that AC current will not work on DC motors because the fluctuations from positive to negative would cause the motor to constantly reverse or deadlock (forgive my non-technicial terms...) thus damaging the motor. I'm not sure, that was just my understanding. Sorry I'm not hijacking this thread I do want to say something to the OP.

ChuggaChugga: I used sectional track on my layout because I had a huge box of it. I used some flex track as well and if I could do it over that is the way I would do it. For all of the info that I have read about hand-laying it is a tedious and lengthy task. No better realism though if you can manage it. It is one of those choices that comes down to can you live with less realism for easier laying of track? Flex looks good and performs well so that is what I would suggest. Definitely check out those websites they are good links for someone just starting out (or someone who has been around for a while but has a lot to learn, aka me!)
 
pb12, no, it is a square wave ac current that the decoder reads as binary bits. The digital imprint tells the decoder to clip the plus or minus parts of the square wave so that the motor only gets the pulses in one direction, and that allows the directional rotation of the armature. It is this reason, the plus and minus pulses, that makes a pure non-decodered DC motor in a locomotive buzz and squeal...it is being excited in rapidly changing polarities for just a brief instant commensurate with the digital signal. What allows you to run a DC motor on some DCC systems is that the controller permits what is called 'zero stretching' so that the bulk of the pulses in one direction are reduced to near zero and the desired pulses have shorter gaps between them. Or, so is my non-engineering mind-picture. :p
 
Aah, I see. Well again you know too much for your own good. I definitely need to look deeper into DCC systems obviously. Thanks for clearing that up for me though! :D
 
I have to disagree with Selector's explanation. What happens in a DCC decoder, the part that goes in the loco, is that the incoming voltage is first rectified, so a DC source is available to run the motor and a microprocessor. The reversals in the signal deliver information to the processor to give it the commands that it then uses to run the motor, lights and sound, using the rectified incoming voltage as a power source, but none of those things will happen in direct sync with the incoming DCC signal. It's as if I sat at a piano and you told me the notes to play: your voice wouldn't convey the actual notes, just the information telling me which ones were required (but note that this is hypothetical, as I don't know how to play the piano). Potentially, you'd be instructing other pianists in the same way, just as a single DCC source can control several locomotives.
 
John P said:
I have to disagree with Selector's explanation. What happens in a DCC decoder, the part that goes in the loco, is that the incoming voltage is first rectified, so a DC source is available to run the motor and a microprocessor.

The reversals in the signal deliver information to the processor to give it the commands that it then uses to run the motor, lights and sound, using the rectified incoming voltage as a power source, but none of those things will happen in direct sync with the incoming DCC signal.

It's as if I sat at a piano and you told me the notes to play: your voice wouldn't convey the actual notes, just the information telling me which ones were required (but note that this is hypothetical, as I don't know how to play the piano). Potentially, you'd be instructing other pianists in the same way, just as a single DCC source can control several locomotives.
Click to expand...

John's gave a good description. But the reversals not only provide commands but also contain an address, so that each device (engine, switch, ...) can be controlled independently. The address/command for each device is sent repeatedly.
 
That is a more accurate account, agreed, that the signal sent to the motor is like a rectified analog DC. But that is not what the decoder gets. It gets the square wave directly from the controller. What it issues to the motor is pulsed and still a DCC signal.

http://www.tonystrains.com/tonystips/dccprimer/intro/dcc-basic-principles.htm

Another explanation stating that the signal to the motor is still pulsed and not true smooth DC of a given polarity:

http://modeltrains.about.com/od/electronicsdcc/qt/decoder_works.htm
 
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ChuggaChugga said:
Thanks for reading this. I've only made a couple of posts so far and I'm about as new to the hobby as it gets.

I've started my research into the hobby mainly by browsing online retailers and looking at the various types of equipment - everything from locomotives to grass and weeds. I also bought a model railroading magazine at a local book store, but most of the discussions in that are still a little over my head. So here are a few questions that I can't seem to figure out on my own! Thanks again for taking the time to offer help/advice.

1. What is DCC stand for -- and what the heck is it? What does DCC ready mean? I believe it has something to do with the "under the hood" function of the locomotives or track. When I was a kid and I played a couple of times with my grandfathers train set, his steam locomotive only did two things -- move forward, and move back. It was made probably in the 1950s, so it had no sound or smoke effects, of course. Now I've noticed that locomotives are getting more and more realistic, if you're willing to drop the $$$ to buy them.

2. Also going back to my Grandpa's train set - the track he had was in small sectional pieces, with no single piece being much longer than 8" or so (HO scale). Each piece had to be joined together, which wasn't a very easy thing to do - if you didn't join them together gently, and just right, you could risk bending a piece of the track and then it would be useless unless you very carefully bent it back. Now it seems like most of the more serious hobbyists make their own track by buying long sections of rail wire. I really like this idea for a lot of reasons, and I think that this is the way I'd want to go. What do I need to know about rail wire? Are there different sizes/shapes for HO? What about different metals? And when you make your own track, do you have to install each individual railroad tie onto the track? That would be extremely tedious, I would think.

3. I think I'm narrowing down what era of railroading I'd want to model, at least to start with. I'm very drawn by 50's era Pennsylvania freight trains and their associated mountainous landscapes. And based on my research of the PRR (thanks, Wikipedia) it seems like the 50's was a time when steam locomotives were still in use, but diesel was becoming the new standard -- which gives me the most flexibility with regard to which locomotive I'd want, since I could really go with either -- though I think I prefer the look of the early diesel engines. Any thoughts about this?

4. Finally - so far the best online site I've found for buying model railroading trains and supplies is www.modeltrainstuff.com. The only reason I say that I think it's the best is because the site is pretty well organized and they have lots of pictures - and both of those things are very important to me since I'm still trying to learn so much! Any other recommendations on good websites to browse?
Click to expand...

Welcome to the hobby and the forum.
i will try to simplfy for you:

1} DCC is Digital Command Control. {DC is Direct Currrent}. DC controls the track voltage to move a loco. DCC uses a computer signal to control the individual loco. WIth DC if you have 3 locos on one electrical block, all three will move when you control the DC powerpack {transformer}. With DCC you can "idle" 2 engines and only make one of the three move on the same one electrical block. Wiring for DCC is far simpler than DC,requires fewer districts and switch on/off trackage. If you have several locos, you should look into a 5 amp booster for your DCC controller. here is a tutorial:
http://www.tonystrains.com/tonystips.htm

2}Ho scale standard straight pieces are 9" long. There IS a "flex track" 36" pieces that are available {except for track embedded in fixed base roadbed}. The flex track can be cut to any length with a cut off tool or a pair of Xuron Rail Nippers. Use the Xuron Rail nippers ONLY on track. Stick to Nickel SIlver track. Alos, flex track can be bent to ANY curve radius you want. If you are new, I would suggest you try a layout with sectional and flex track BEFORE trying handlaid track. It can be tricky. Master the other aspects of MRRing {Model Rail Road ing}- such as wiring,benchwork, scenery items first. Just my two cents worth.

3}The 50's is the "transitional era" when steam was on its way out, and diesel on its way in. you can run either/or or both. MAny like that idea. If you really like the early diesels, have at it!!! Google research for your favorite RR will tell you when/what models they were running when so you can decide what to run.

4} your link is a good one, I also like ;
http://www.wholesaletrains.com/HOProducts2.asp?Scale=HO&SPECIAL=0
this one is considered the "bible" for modelers:
http://www.walthers.com/

both have good pictures. Both offer good service.

Also check out Kalmbach {publishers of Model Railroader Magazine} books to READ READ READ before you start buying stuff. It will save you money and heartache later!
http://www.kalmbachstore.com/modeltrains-railroading-model-railroading-books.html

Good luck and enjoy the hobby!!!
:)
 
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