# New layout in the works



## ExP_Razor (Apr 26, 2010)

Hello, I'm new here and I've joined the forums to possibly get some assistance in designing a garden railway that I'm just starting to get ideas for. Actual construction won't be starting for atleast a year due to various reasons but I'm well into the planning stages and there are a few points I'm not sure about. 


The first I would like to address is DCC (Digital Command Control). Having run HO for quite a while and having run Digitrax's DCC system for my equipment for over 10 years now, I'm trying to figure out how viable it would be to use it on a large scale layout and what equipment I might need to run a large scale layout compared to a club-sized HO layout. If possible I would like to use Digitrax again so I can continue to use the same throttle I have from running HO (The throttles are compatible with all forms of DCC made by Digitrax). 


Next is the exact scale I'm thinking of running. At this time I'm thinking of primarily running 1:20.3, modeling three different railroads, namely Denver & Rio Grande Western, Big Trees & Pacific (modeling the original logging railroad if I can find enough information) and, the now local to me, Nevada County Narrow Gauge RailRoad. 


Another issue I'm having is figuring out what types of grades may or may not be too steep for a railroad that is not cog assisted. For the logging area I intend to have somewhat steep grades with switchbacks while the main line has shallower but still moderate grades. I have not had the opportunity to gauge the percentage of the slopes, partially due to a lack of knowledge and/or equipment necessary to do so.


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## kormsen (Oct 27, 2009)

DCC - i am sure, that others will give you more council about this, than you want... 

scale - that depends on your preferences. do you like lots of assecoires? than go 1:24 or 1:32. do you like european? then go 1:22.5 

grades - depends on how long your trains will be. 2% (one in 50) for very long trains. above 4% (one in 25) you leave safe terrain.


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## ExP_Razor (Apr 26, 2010)

As I said, I would prefer to us a Digitrax DCC system if I can figure out how to do it with large scale equipment, I've already got a scale in mind to model (1:20.3), and on the main line I would not want any more than what could be considered moderate grades. In the logging area however, if I'm able to accurately emulate the real thing, both the shay and heisler type locos should be able to drag loaded log cars up grades as steep as 6%.


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## Greg Elmassian (Jan 3, 2008)

There's nothing to large scale DCC, you just need more amps and "bigger" decoders. 

Remember that multiple locos can use up 5 amps pretty quickly. I use a 10 amp booster, and might go up a bit from that if the new Zimo proves out. 

Digitrax decoders may be marginal on some of the larger locos, also you may want a combined motor/sound decoder. 

There's lots of good threads in the DCC forum I suggest you read, rather than me retyping all the good ideas already written down in the forum. 

You can visit my site, and read the DCC sections. 

Regards, Greg


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## ExP_Razor (Apr 26, 2010)

Well I already know that the base system I want to use is Digitrax, the individual decoders can probably be of other brands, especially when considering sound but for the wiring of the system, I want to be able to have it run off of my DT400R. 

In regards to other threads addressing DCC, there doesn't seem to be a clear subforum to look in. If you know any threads in particular, links would be appreciated.


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## ralphbrades (Jan 3, 2008)

In the logging area however, if I'm able to accurately emulate the real thing, both the shay and heisler type locos should be able to drag loaded log cars up grades as steep as 6%. 

Err no... What you have forgotten is the fact that your loco is driven by an electric motor at constant voltage. This means that to power up your inclines it draws more current from the source. The heating effect of this is the SQUARE of the current. Thus if I draw 1 Ampere the heating effect is 1. If I draw 2 Amperes the heating effect is 4. If I draw 3 Amperes the heating effect is 9. If I draw 4 Amperes the heating effect is 16... Unless you are in a position to design your loco to use force cooling or use motors with self cooling fans in them -I would be very wary of stepping outside of the 1:25 incline envelope. It might look very realistic -but very expensive as your wiring catches fire... 

regards 

ralph


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## 6323 (Jan 17, 2008)

I've run Digitrax on my small layout. Tried running 2 Aristo GP40's, but trips the circuit breaker in about 5 minutes. 
Yeah, running track power, on about 45 foot of track currently. 

Recently, I just got the new NCE G-Wire throttle. Works fine, along with my MTH Z-4000 transformer. 
Have never had a problem running it, with 2 or more locomotives. 
And with expansion project underway, I think, for me, the MTH/NCE combo should work out great for me. 

My opinions, based on personal experiences. 
Mileage may vary.


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## ExP_Razor (Apr 26, 2010)

Ralph: The primary problem that you're overlooking for that is gearing ratios, a much lower gear ratio than what would be used on a fast mainline loco is what I'm looking for. Along with much greater torque, I would also expect the top speed of the loco to be much slower, both the shay and heistler types can't get much above 20 MPH on level ground with 15 being the usual accepted norm. On the hill I would expect both to be crawling at a slow but steady pace. For what I'm looking for, the gearing ratio of the electric motor would have it so that the same RPM used to make a model GS4 run at a scale speed of 100 MPH on level ground with a string of long and heavy passenger cars will make a lumber loco with a MUCH lower gear ratio climb a %6 grade at 5 to 10 MPH (scale) pulling loaded log cars that are less than half as long as those 85 foot streamliners.


For an example of gear ratios, say the difference between the electric motor spindle and the driving wheels on the model daylight engine was a 1 to 3 gear ratio, meaing for every 3 turns of the electric motor, the drivers will make one full rotation. This is ideal for an engine designed to have a high top speed however at the same time it greatly hampers how much it can pull or how steep a grade it can climb. On the other hand we have a model shay which has an electric motor to driver gear ratio of 1 to 48, meaning that the electric motor needs to spin 48 times for the drivers to spin once. And then you have the diameter of the drivers, a prototype GS4 has 80 inch drivers while most geared locomotives have between 40 and 50 inch wheels, not much bigger than those of the rolling stock they pull, which also contributes to the amount of tractive effort.


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## Axel Tillmann (Jan 10, 2008)

I would love to send you some basic PDFs ("Fundamentals of layout work", "The World of DCC") so would you be so kind to send me an email to [email protected] since your "send msg" is turned off?

Axel


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## Bob in Kalamazoo (Apr 2, 2009)

I've only run into a problem with my Digitrax DCS200 tripping out when I tried running four trains on a hot day, with one of the trains consisting of four streamlined lighted passenger cars. And then it only tripped out after running for close to a half hour. I took one of the trains off the layout (parked it on a sliding) and the layout ran fine the rest of the day. On a cool day I can run four trains, two Aristo FA1's, one Aristo Mallet, and one Aristo RS-3.
Bob


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## ExP_Razor (Apr 26, 2010)

Axel: I've adjusted my account settings so you should be able to send PMs now. 

In regards to the boosters, with how many locos I intend on running once the whole thing is in I will probably need a total of four 8 amp boosters to cover everything. The big money question however will be weather or not idle locos will be pulling amperage from the rails or if I can go with a smaller number of boosters. If every loco takes up to 3 amps, even if it's stationary then that many would be required with what I have in mind although probably only one of them needs the command station (the one closest to the house).


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## ralphbrades (Jan 3, 2008)

EERRRMM.... You are a newbie and actually *I do* know quite a lot about electrical systems, electrical motors, torque curves and gear ratios. I would suggest you have a look around the home page of "The Cabbage Patch Railway"... 

The Gauge '3' Society has in development a "Technical Manual" which runs to 475 pages of A4 -most of which I have written. 

regards 

ralph


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## ExP_Razor (Apr 26, 2010)

I may be new to the forums but model railroading is something I am NOT new to, I have done HO for quite some time and the same principles apply to this scale, adjusting for the size difference. You are talking about overworking the motor at an RPM high enough to burn up the wiring, I'm talking about a motor that doesn't need to work as hard because the gear ratio is low enough to handle the strain without causing a problem.


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## Greg Elmassian (Jan 3, 2008)

I reread both of your guys' posts. I understand what Ralph is saying about the effects of greater load and the heat rising as the square of the current/power. (I have a few college degrees also). 

But I read ExP_Razor to be talking about what he mentioned also. 

Recently I had occasion to try several different gear ratios in a locomotive under regular and maximum loads. I destroyed a "tall" geared setup 1:11 gearing in a pittman... it worked great until the motor overheated melted the glue holding the windings then locked the rotor and then melted a few other things, including a NCE D808 decoder, rated at 8 amps continuous. 

I put a much lower geared motor in (1:48) and pulled the same load, much more slowly, and the motor would not pull over 1/2 amp. 

So, I've experienced the "truth" in practical experience of both of your points guys. 

Regards, Greg


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