Bachmann Message Board

Discussion Boards => Large => Topic started by: Texas on July 27, 2007, 04:52:38 PM

Title: G-Scale Power
Post by: Texas on July 27, 2007, 04:52:38 PM
I have a G-Scale White Pass Steam Engine and cars.  We have set it up on a wall shelf that encircles a 12’x12’ inside room.  We purchased the train set this year and it generally runs well in this set-up.  However, the train requires that I turn the power knob to approximately 65 for the train to begin to run and keep a fairly steady speed.  The train slows down at the far end (furthest away from where the power supply connects to the track) and picks up speed as it gets closer to the power supply feed.

It was suggested to me by a friend that I could attach a second power supply to the track on the other end to provide more even power to the train around the entire track run.  My question is to determine if this is a safe configuration (i.e. two power supplies attached to the tracks and providing power to the train simultaneously)?  Will it improve performance?  Will it negatively effect the train?

I have followed all instructions in setting up the track and train.  I have good, tight, smooth connections between all sections of the track, have used the track clips and I have the track tacked down to hold it tightly together (short nails through the holes in the plastic tie-rods provided in the track sections) as well..  I have the Bachman train maintenance kit (contact oil and grease) and have used approved track cleaning fluid.

Your advice would be appreciated.

Title: Re: G-Scale Power
Post by: VirginiaCentral on July 27, 2007, 07:47:53 PM
Don't add a second power supply!

You are suffering from voltage loss over the distance of your loop because the rail is not effecient at carring the current.  You need to run feeder wires from your power supply to the far end of your loop.  Make sure you don't cross the wires or you casuse a direct short.

Title: Re: G-Scale Power
Post by: JerryB on July 27, 2007, 07:49:08 PM

DO NOT hook another power supply to the same track with out some type of electrical isolation. There are a number of problems that can result, with most of them having the potential to destroy at least one of your power supplies.

Your problem is simple and can be solved. When the train operates as you have described, it's probably the result of voltage drop through the rails or connectors. The track is simply not conducting the available power to the furthest points on the loop. Some questions and suggestions:

What brand and / or type of track you are using? If it's Bachmann's, it's made from pressed steel. That material is  not highly conductive as compared to solid brass or other metals. Additionally, it tends to corrode (rust) at every joint. The rust produced is a very good insulator, thus further limiting the conductivity. Replacing the steel track with brass track is a good solution to consider.

Is the power supply the one that came with the set? Set power supplies are usually the absolute minimum required to get the train around the circle of set track supplied. The required power supply rating is generally not connected to the length of track, but if you are starting with a power supply with marginal output (your 65% power when close to the feeders), every foot of track or track joint really works against you. For your single loop, you most probably need to upgrade the power supply to something around 5 amps. These are readily available.

A final suggestion is to provide power feeders to one or two more places around the loop. Use 10 gauge or 12 gauge wire hooked directly between the existing power supply and the rail at points about 1/2 or 1/3 way around your track. Make certain you maintain correct polarity for the additional feeders. Many of us would consider that a simple 12 foot 'round the room' loop wouldn't need additional feeders, but when you add the steel track, small power supply and the additional track (~45') as compared to the circle of track (~13') that comes with most sets, it will probably be your most immediate and cheapest solution.

Hope this helps & Happy RRing,


Title: Re: G-Scale Power
Post by: Texas on July 27, 2007, 10:55:32 PM
Many thanks to both of you.  I now have several things to consider.

I am running Bachman steel track.  All of it I purchased new, but I did have to reduce the size of two sections to adjust the loop size to make it fit the layout.  This was fairly easy to do and the job came out clean.

I will consider brass track... but I would rather not have to replace all the track now.  Instead, I think I will try the feeder wires (I'll be careful about polarity) first.  And if that doesn't work, I will try replacing my power supply with a 5 amp model.

If I understand the feeder wire suggestion, I would solder a 10 to 12 guage wire to each of the '"ears" on the track power connector where they come in contact with the track.  Then run the wire around the loop and solder the other end to a spot on the track about halfway around (watching that the wires remain connected to the same track side).  Is that correct?

Thanks again!


Title: Re: G-Scale Power
Post by: altterrain on July 28, 2007, 12:11:35 AM
Like the other guys said - NO, to a second power supply. Yes, to a better power supply. and Yes to more power feeds (one or two more). 16 gauge wire is more than enough. I use primarily 16 gauge for my outdoor layout and only 14 gauge for the longer stretches (over 30 feet) running up to four locos on a loop with no troubles. Since you are indoors you can use 16 ga. lamp cord or even speaker wire. I use Bachmann track for indoor holiday trains. I soldered  the power feed wires to the inside of the hollow part of the rail. I run this track off an old 2 amp MRC pack meant for HO but works fine. Also, Bachmann track and loco wheels can get dirty so just clean them off with alcohol on a rag.


Title: Re: G-Scale Power
Post by: JerryB on July 28, 2007, 04:27:04 AM

The closer to the power pack you make the multiple feeder wire connections, the less voltage drop you will see. In other words, try to connect the two or three sets of wires directly to your power pack rather than to the track.

Brian's suggestion to use 16 ga. wire is fine, but the bigger the wire, the less the voltage drop. I would definitely use the stranded wire he recommended. Zip cord or speaker wire will work fine.

Do consider a larger power pack. I'm certain you are working at the limit for the set power pack.

And I agree that replacing the rail should only be considered if increased feeder wires and / or a new power pack do not provide the desired results.

Happy RRing,


Title: Re: G-Scale Power
Post by: Paul W. on July 28, 2007, 07:56:46 AM
In our basement we have a two loop suspended layout using the Bachmann track. The outer loop is 54ft, the inner is 47ft. I am using the stock power packs that came with the starter sets. When we do the garden layout, I'll use a much bigger power source, but for the inside loops, the stock ones work fine.
Just add another pick up point on your layout and you will be fine.
Just a hint, pick up a track cleaning pad from San Val and put it under a caboose. Run this occasionally and you won't have any dirty track issues.

Title: Re: G-Scale Power
Post by: Texas on July 28, 2007, 10:15:53 AM
Thanks to all for the insight and suggestions!

I think I clearly get the concept of the additional power feed(s) from a single power supply.  I also understand the need to keep polarity correct.  And I see that I can connect the additional power feed "tag" ends (other end from the power supply) to the track by either soldering or using another stock track power clip (I have an extra one).

However, I am still a little fuzzy on where/how to connect the additional power feeds to the power supply?   I appreciate Jerry's statement about connecting the additional power feeds directly to the power supply... but how does one do that? 

I could solder additional power feeds to the "ears" of the primary track power clip... I could splice into the wires coming from the power supply to the power clip to add the additional power feed wires... or I could open the power supply and solder additional power feeder wire(s) directly inside (i.e. more RC jack electrical outlets on the power supply)?  What to do, what to do?

Any pictures of additional power feeds connected to a stock power supply would be appreciated or just more detailed information on to do this easily and correctly.  I just can't picture the best way in my mind from what I have heard thus far.

I do appreciate everyones time and insight!  I'm getting closer to acting, but I don't want to experiment adding the additional power feeds to the power supply without some detailed information or a photo to look at and plan from first.

Thanks again,


Title: Re: G-Scale Power
Post by: altterrain on July 28, 2007, 12:17:53 PM
Nothing tricky. I am not sure what the connectors are on your power pack but splicing them together can be done just about anyway. You can twist them together and tape them, solder them and put some heat shrink tubing on them, use a wire nut, etc. My transformer has the old fashioned screw terminals so I ran both feeds to a single spade lug and crimped them.


As you already know, just make sure you keep track which one is the inner rail and outer rail feeds.


Title: Re: G-Scale Power
Post by: Matthew (OV) on July 28, 2007, 12:46:28 PM
Does this help?  (Now, remember, that was written for HO, so varous things about wire and track sizes are a bit smaller than you'll be using... but the principle is the same.  Please don't use doorbell wire to power any large scale railroad you'd like to keep!)

You can use "terminal tracks" ... clamps... or really just about anything that makes electrical sense to attach the "Feeder" wires to the track... with brass track you can generally solder your wires on, screw them to the bottom of the rail using ring terminals, or there are connection devices you can buy (power railclamps by Hillman's come to mind) ... since you're using Bachmann set track (shudder!) you may have to modify the approach a bit because of the hollow rails.  Once you have your feeders set up, you can connect (twist?) all of the wires that go to the same rail together... meaning you'll have two twisted bundles of wires.  Adding an extra piece of wire to this, with a wire nut, you'll now have two wires to connect to your power supply .... and the power will be distributed around the layout.

You probably don't want to open up the power supply unless you have to... it's easier just to treat that as a "black box" and splice the wires outside.

On mine, the power supply feeds a panel, where toggle switches distribute the power to blocks on the railroad.  I have put insulating connectors between these blocks, and can shut them down independantly, allowing trains to be "parked" on sidings, and so forth.  Yours is something of a one train -- one crew operation, so you don't need the switches... you just need to distribute the power feed a bit.

Matthew (OV)

Title: Re: G-Scale Power
Post by: JerryB on July 28, 2007, 01:40:27 PM
I don't know what your current power supply connections look like, and how far it is from the PS to the track, but here are some suggestions:

In the original responses, I recommended adding one or two extra feeders. From Paul W's input, it sounds like you only need to add one new feeder.

I would not do anything that permanently changes the PS nor would I open the PS. Even a foot or so of smaller wire isn't at all critical. I would make the existing wire from the PS to track larger if it is something like the 20 or 22ga. that is typical of set stuff, or if it is very long. The fact that you need a high setting on the PS to get the train going points to the possibility of significant voltage drop between the PS and the track. Larger wire would fix that possibility.

If the PS uses screw terminals, use the largest wire that will comfortably fit under the screw. A few inches of that wire will provide a place to strip and solder the extra wires for the split. The wire from the PS can go directly to one track hookup point with the extra connection to the new point. Get some shrink tubing or electrical tape for insulating the junction points.

Another possibility is to use a small multi-point terminal strip, with the distribution accomplished on it. Again, near the PS. Terminal strips are available at home supply (Home Depot, Lowes) and electronics stores (Radio Shack) as well as on-line.

Soldering the new wires to the existing track clip would be my last choice, but even that should be better than what you now have.

I'm certain others will make suggestions, but the main thing is to keep it simple!!

Let us know how this work out.

Happy RRing,


Title: Re: G-Scale Power
Post by: Texas on July 28, 2007, 05:09:24 PM
Once again, great input.  I'm getting closer to understanding and making an effort to correct the problem.

My power supply is a standard Bachman kit power supply.  It's tan, with a speed dial and direction control on the face.  At the top, side are two RCA style input (female) jacks.  One is where the transformer plugs into and the other is where the output wires (about 20ga) plug into.  Those output wires end with a slip-on connector (a spade) at the end that connect into a track clip that spans the tracks and makes the connection to the rails.

I appreciate the advice not to open the the power supply.  Based on the input, and the "keep it simple" advice, I think my best choice is to get a multi-point terminal strip, splice the primary power output wires to it, reconnect the primary power track clip from there, and create a couple of additional power feeds from the multi-point terminal strip that connect at the quarter and halfway point around the run as well.

I'm beginning to layout the wire runs in my mind and will proceed slowly to do a clean and efficent job.

Now, I think I have what I need to begin and many thanks for all the advice!  I have the children this weekend and a vacation planned, but I will let you know how it all turned out once I get to it.

Thanks so much!


Title: Re: G-Scale Power
Post by: Texas on August 30, 2007, 11:56:33 AM
Many thanks to everyone that replied and gave advice and instruction. 

Here is what I've done.  I cut the original (20ga?) wire that connects the power supply to the track power clip and put electrical connectors on the ends I cut.  I purchased a simple power distribution block from Radio Shack (allows for 4 additional power feeds from the single power input) and screwed it down, out of sight and close to my power supply.  I then connected the input power wire (the PS side of the wire I cut earlier) from the power supply to the power distribution block and ran the first power feed (using the track side of the wire I cut earlier) to the original track power clip.  I then ran an additional power feed (16ga wire) from the power distribution block to second track power clip halfway around my track run (being careful to test polarity).  And Viola, I'm back in business!

Hope my description wasn't to confusing, but in short, it was clean and easy to accomplish.  I didn't change the power supply.  And using the power distribution block, some electrical connectors and the additional track power clip made the job possible without having to soldier anything.  I used wire clips from Lowes to neatly trace the second power feed wires around the track where it won't interfer with the train's operation and it can't been seen.  The single additional power feed seems to be all that was required with my run and the train is working smoothly.

Again, thanks to everyone for the help!