Usa trains gp38-2

chris m01

chris m01

Registered
24 Oct 2009
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Birmingham, UK
I find the GP38 bogies are very free turning.
I have posted this before but it fits this thread
 
idlemarvel

idlemarvel

Registered
13 Jul 2015
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Ascot
Like I say my main line is all aristocraft r2 so I should be okay and all my stock has hook and loop couplers so that should help as well
Looks like it's all systems go then. Have a look at Greg's DCC link earlier for advice on how to chip it. Have fun. :)
 
Adam1989

Adam1989

Registered
11 Mar 2018
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Calne wiltshire
I take that a massoth xl decoder will be good enough for this
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
23,671
555
Tamworth, Staffs.
I take that a massoth xl decoder will be good enough for this
I would tend to use an XXL. - These can be 'hungry' beasts!
I am not sure an XL would take kindly to a full-stall?

As has been stated, a 5 Amp controller would be a minimum, really. One of these, plus 'something small' would probably be OK, but don't be surprised if a 5 Amp controller shutsdown due to heat.
I use a 3.5 Amp bench supply for testing, and setup.. If the motor's are a little 'tired', I can hit the limit on this, at times. - Single engine on rollers, so little load. Imagine out on the track, with curves, and pulling stock.

PhilP.
 
Adam1989

Adam1989

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11 Mar 2018
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I would tend to use an XXL. - These can be 'hungry' beasts!
I am not sure an XL would take kindly to a full-stall?

As has been stated, a 5 Amp controller would be a minimum, really. One of these, plus 'something small' would probably be OK, but don't be surprised if a 5 Amp controller shutsdown due to heat.
I use a 3.5 Amp bench supply for testing, and setup.. If the motor's are a little 'tired', I can hit the limit on this, at times. - Single engine on rollers, so little load. Imagine out on the track, with curves, and pulling stock.

PhilP.
I have a LGB 5amp transformer, so if I would run this and my mallett together would it overload the transformer. My mallett and franks are okay running together both twin motor locos.
 
Rhinochugger

Rhinochugger

Retired Oik
27 Oct 2009
25,378
604
North West Norfolk
Yes, USA Trains locos are renowned for being current-hungry beasts :nod: :nod: :nod:

Your Mallet and Frank S both have different types of motor (from USAT) and probably both together will not draw as much current as the USAT under load.
 
Adam1989

Adam1989

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11 Mar 2018
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Hmm okay that's something to consider before I make a purchase at least I found that out before I bought one thanks guys
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
23,671
555
Tamworth, Staffs.
I have a LGB 5amp transformer, so if I would run this and my mallett together would it overload the transformer. My mallett and franks are okay running together both twin motor locos.
It depends.. - Sorry, but it does depend on the following:
1. Length of train. - The longer the train, the greater the load on the loco, and needs more 'oomph' to pull.
2. curves. - More drag, more current needed. Reverse curves, even worse.
3. Gradients. - Takes more to go uphill.
4. Smoke. - Turn it off! End-of!! Probably 750mA on the Gp38-2 alone for smoke.

So, if you run short trains, and tend to have a loco sitting in a station, then you will probably be OK for a reasonable running session.
If you have R1 curves, and a model of the Rocky Mountains, with prototypically long trains, then you will not be able to run for very long.

Also, don't have your transformer (and controller) sitting out in full-sun. - I know, British climate, but it has been a little warmer of late.
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
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Tamworth, Staffs.
It may seem 'doom and gloom', but it depends what you want from your railway?
Rule 8 - Your railway, run what you want..

If you *really* like a certain loco.. Then either build your line to a prototype to suit, or just run it anyway, and enjoy! :) >:)>:)
 
Adam1989

Adam1989

Registered
11 Mar 2018
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Calne wiltshire
It may seem 'doom and gloom', but it depends what you want from your railway?
Rule 8 - Your railway, run what you want..

If you *really* like a certain loco.. Then either build your line to a prototype to suit, or just run it anyway, and enjoy! :) >:)>:)
Thanks for all your info Phil I'll give you some I info on my railway.

1 controller and base station are in the shed no sun

2 the line was built with no gradients in the hope one day I could have live steam.

3 the main line is all r2 with no reverse curves.

4 i have a total of 4 box cars and one caboose as my garden is not very big

And well said it's my railway maybe I'll buy it run it hope for the best and enjoy it.:)
 
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PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
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Tamworth, Staffs.
And well said it's my railway maybe I'll buy it run it hope for the best and enjoy it.:)
At least it isn't a great big Aristocraft loco! - There three-axle bogies ('trucks' in US parlance) have two motors, and three 'gearboxes' per bogie.

:devil: If all else fails.. You can fill it full of batteries! :devil:
Enjoy!

PhilP.
 
Rhinochugger

Rhinochugger

Retired Oik
27 Oct 2009
25,378
604
North West Norfolk
 
Greg Elmassian

Greg Elmassian

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8 Mar 2014
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San Diego
www.elmassian.com
A note on current:

When running at constant speed, USAT locos are not terribly current hungry, but they have an often misunderstood characteristic: to put it simply they pull a lot of current off a dead stop. This is commonly referred to as "Stall current".... so while it might only draw a couple of amps under way, some USAT locos will draw very high current for a brief time.

How decoders handle this varies considerably, some decoders have "running current" and "stall current" ratings very close, and some are engineered to tolerate a very high stall current.

So, there are a lot of misconceptions out there, and confusion.

In this case, it would be best to use a decoder rated a minimum of 5 amps continuous, to try to simplify your decision. I do have a number of USAT locos "chipped" so I can speak from experience, as I date to the days when only one US decoder manufacturer would guarantee their decoders on USAT locos (NCE D808 decoder).

Hope this helps understand some information that may seem conflicting.

Greg
 
chris m01

chris m01

Registered
24 Oct 2009
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Birmingham, UK
I have measured the amps drawn by USAT locos pulling six wagons. It tends to be around 2 to 2.5 amps. Somewhat surprisingly the lights seem to be nearly half of this draw. So either switching off the lights or swapping to LEDs would significantly reduce current draw. When testing on my low current power supply switching off the lights is all I need to do to stop overloading the transformer.
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
23,671
555
Tamworth, Staffs.
So either switching off the lights or swapping to LEDs would significantly reduce current draw
Just be aware that, like Aristocraft, USA Trains tend to mix LED's with filament bulbs.. This can make 'swapping to LED's' a little less of the trivial exercise it ought to be. - Though less-so, than converting things to DCC.

Not, IMHO, an exercise for the first-timer. - Though dependent on your level of knowledge in electronics.
 
P

phils2um

Phil S
11 Sep 2015
348
123
Ann Arbor, Michigan
I find the GP38 bogies are very free turning.
I have posted this before but it fits this thread
I've done this too many times by mistake with disastrous results!!! :eek::eek::eek:
 
Chris Wright

Chris Wright

Rev-Up
7 Jun 2016
103
5
Cumbria, penrith
These locos of which I have one run on R3 Piko and R2 LGB no probs due to only a twin axle arrangement which allows anything except R1 curves and points.
 
tac foley

tac foley

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11 Apr 2017
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Near Huntingdon, UK
I've had my BNSF GP38-2 in war-pumpkin colours for years, after finding a photograph of the actual loco online. It's a real sweetie and happily runs on a mere whiff of V and A.
 
PaulRhB

PaulRhB

Registered
I've had my BNSF GP38-2 in war-pumpkin colours for years, after finding a photograph of the actual loco online.
Need to get a BNSF swoosh one next then ;)
Railpictures.net and rrpicturearchives.net are good sites for specific locos.
The H1 pumpkin never really did it for me which is why I’ve now gone for repatched original yellow bonnet SF and now the latest Swoosh that I really like.

(I’m pedantic enough ;) to avoid the red warbonnets as they never actually carried that on the Gp38’s and SD40’s, does suit the F’s and Dash-9’s though :) )