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Discussion Starter · #1 ·
Hi,

I have 2 reversing loops in my new layout that I am having some derailment issues with (even at very slow speed). What are the best practices for laying track?

1. Can I get away with a slight gradient (1%) on a 7' diameter curve running a K-27 (which they recommend 8' diameter minimum)?

2. Do you think I would have less derailments if I banked the curves slightly so they were leaning in?

3. How level does track really need to be (not gradient)?

Best regards,
Ted
 

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RE: Track: Derailment issues & how level does it need to be

Side to side level is probably the most important especially at switches. Banking the curves (super elevation) prudently could help with long trains but shouldn't be needed if you are running shorter trains except maybe for looks. Abrupt dips in the track can affect operation but grades themselves shouldn't be a problem except when too steep for the locos to pull their train.

As to minimum radius, the wider the better. You might be able to negotiate a tighter radius if you spiral the approaches, that is use a wider radius to enter and leave a smaller radius.

One of the most common causes of derailments in largescale is faulty wheel gauge. Check your wheels to make sure they're in gauge.
 

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RE: Track: Derailment issues & how level does it need to be

On curves being level side to side is the most important, banking on curves by 1:1 RR's and highways is done mostly where speed is a factor....also the transition from level to any grade should be done on straight track.
 

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Ted:

We might be able to help you a little bit more if you gave us some more information:

1. Does the train always derail at the same place, if so where on the track is it, curve, straight, switches or transition between straight and curve?

2. Is it the engine or the cars that derail?

3. Are you using the K-27 (Bachmann or Accucraft)or some other engine, if it is another engine what is it and who made it?

4. Whose track and switches are you using? 7'diameter is not a common commercial curve. LGB's diameters are 4', 5', and 8'. I had to replace all my LGB 16000 switches with Aristocraft large radus switches (10' diameter) when I got my Accucraft K-27. It would not go through the 16000 series switches. I am now in the process of replacing all my switches with LGB 18000s (17' diameter). Fortunately, I got all I needed before LGB went the way of the Dodo bird.

5. Is the switch coming out of the reversing loop thrown automatically or are you relying on the engine to push it over? My experience with switches is that only LGB steam engines will routinely go through and open closed switches. The leading trucks on other manufacturer's (Aristocraft, Accucraft, Bachmann) steamers will derail.

Unless you are running battery or live steam, I would get rid of the reversing loops and run a parallel track, sort of a dog bone shape. Reversing loops outdoors can be a real pain in the neck.

I think that some people have talked about running K-27s on 8'diameter curves (all of my curves are 10' diameter), I don't recall anyone mentioning that they had run it on tighter curves. All of the Bachmann K-27 drivers are flanged. There is a limited amount of side play in the drivers. Therefore they might ride up and off of the rails if the 7' is too tight. If it is the engine and it always derails at the same place you should get down on the ground and run the engine slowly through that section of track and carefully watch it. That is something that I have had to do occasionally. It took me two years of fiddling before my K-28 would go around my track once. Now it runs like a champ.

Chuck N
 

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Ted:
This is probably not what you want to hear, but...
I have made some measurements and I would be very surprised if the K-27 will navigate 7' diameter curves.
I put my Bachmann K-27 #455 on three different diameter curves: LGB 18000 series (17' diameter), Aristocraft wide radius (10' diameter) and LGB 16000 series (8' diameter). I didn't run the engine, this was all done static.
I measured and checked the following. The distance between the closest point between the engine and tender and how much lateral play there was in the drivers.
With the 18000 curve the closest point is 1/2" (0.5) and there was a lot of lateral movement of the drivers.
The closest point with the Aristocraft 10' diameter track is 1/4" (0.25) and again there was lateral movement of the drivers.
The closest point with the LGB 16000 track is 1/16" (0.0625) and there was no lateral movement on the drivers. In fact it was difficult to place the engine directly on the curved track. The fit was sufficiently tight enough that I think that there would be extensive wear on the inside of the outside rail. While it will go around this tight of a curve, I would not recommend it. Over time it will add sufficient wear and tear to the track and engine to cause problems.
Extrapolating the line on the graph below the engine and tender will touch at a diameter of about 7.5 feet. This by itself will cause derailing if the track has a diameter of 7'. I also think that the drivers will ride up on the rail when entering the curve and this will also cause it to derail.

Sorry for the bad news.
Chuck
 

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Discussion Starter · #6 ·
RE: Track: Derailment issues & how level does it need to be

Hi Guys,

I really appreciate your help. I spent several hours today watching the train go through trouble spots, then correcting them one by one. The Bachmann k27 is now working very well on my layout. I don't know the actual diameter of the curves I have, becuase I am using flextrack, but my smallest is roughly 7 1/2 feet. It's a tight fit, but is working now without issues and I have run the train over it about 30 times without incident.

This is my first g-scale layout and I am really learning as I go. my issues today included:

1. Having to file/dremel the ends of track smooth where i had cut them with an angle grinder. Then I joined them with a splitjaw clamp. Before doing this, I had small burrs that were causing issues. I learned the any curve is very sensitive to a joining track.

2. Having to side to side level track in and leading into a curve.

3. having to regrad some of my layout to smooth out a curve and keep it level in all directions.

4. re-oiling the k-27 very slowly and making sure to get all moving parts.


At a later date, i will send some pics of my layout. I built a waterfall that is about 7' tall, 6 feet wide in each direction and have a curved tunnel that the train goes through (roughly 10' diameter curve). I was so relieved when the train went through it the first time becuase there is so much stone (20k pounds in the entire waterfall) on top of the tunnel. Now that everything is working, I look forward to building structures and tweaking the layout. I would appreciate it if you could give me some more advice on the following topics.

A. In some cases, I have small gaps (~
 

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RE: Track: Derailment issues & how level does it need to be

Ted:

Glad that you were able to solve the problem(s) and get the train running. I know how frustrating it is to have constant problems with keeping the train on the tracks.

I still have a few cars that will always derail at the same spot. I have tried everything. The only thing that helps is to turn the car around. Then it runs fine.

Chuck
 

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RE: Track: Derailment issues & how level does it need to be

I have had many problems with Aristo U-25-B. Solved with leveling track side to side and adding additional weight, and lowering the center of gravity. Track geometry is the biggest issue.......I have track in floating ballast and this means adjustments from time to time.
 

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RE: Track: Derailment issues & how level does it need to be

Ted, when you say you have to slightly move the K-27 after it stops. That is the classic issue with the counterweights being loose. Have you replaced them? There are free replacements you can get from Bachmann. Before I replaced mine I had the same exact issue. It's not a connectivity issue, it's the loco gets stuck.
 

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Discussion Starter · #11 ·
RE: Track: Derailment issues & how level does it need to be

Hi Jim,

I was told when I purchased it that it was the "new" batch from Bachmann with the updated counterwieghts. Any way I can double check this by looking?

Also, just gave myself another issue. Last night I was running the train while cutting my lawn and left it for a few minutes. Sure enough, at one of the switches, the locomotive went one way and the tender went on the other track causing a derailment. The locomotive was sitting perferctly on the track while the tender was across two sets of track laying at a 30 degree angle. I replaced them on the track and it the train wouldn't move. I then replaced them right next to my track power and it would intermintantly get power. I could tell by the lights going on then off. It would only move very slowly and jumpy, stopping more than moving. I took it off the track, examined it, turned the wheels and everything looked fine. Then I checked the electrical wiring in the tender. Looked fine also. I put some conductive lubricant in a few spots, then replaced it on the track. This time it went further without stopping. However, then it stopped and the intermittent on/off is happening again. What do you think I should do? Thanks for your help. - Ted
 

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RE: Track: Derailment issues & how level does it need to be

Ted:

If you are having counterweight problems, the main drive rod will not be straight across all four drivers. On mine the connecting rod between the #3 and #4 driver was at an angle. Probably about 20 degrees off straight. This jams up the motor and could make it appear to be an electrical problem. It took me several times looking at the engine before I noticed the rod wasn't straight.

Chuck
 

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RE: Track: Derailment issues & how level does it need to be

Ted, besides what Chuck noted, if you can wiggle the counterweights then they need replacing. The more you run the loco the looser the counterweights will get. The counterweights on the third axle are almost always tight and don't need replacing, if the counterweights on axle #1, #2 and #4 aren't as tight as the ones on the #3 axle, they need to be replaced. I would double check even though you were told they were replaced.



It is also possible the counterweights were replaced but the side rods put back on wrong.



You can call Bachmann, they will pay for shipping both ways for you to send in the loco and replace the counterweights at no charge.



Even if the counterweights are on tight (can't wiggle them - sorry don't know a more technical term :) then you might want to call Bachmann as it has to be under warranty as these only came out this year.



Before that though,
- Are you using rail clamps between rail sections?
- Have you cleaned your track? What do you use to clean it? Sometimes track can look clean but isn't. Many use a wall pole sander (you can get them at Home Depot or Lowes). I use one at it does a real good job and fast. Some use it with wall pole sand paper (has large holes in it - not like wood sand paper - looks more like a screen) and others attach a scotch brite pad to the pole sander instead of using the pole screen.
 

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RE: Track: Derailment issues & how level does it need to be

I use a drywall sander with a green Scotch Bright pad. I wouldn't recommend sand paper. I tried a very fine sand paper (emery) many years ago and it really scratched the track. The scratches then tended to accumulate more dirt.

Chuck
 

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Discussion Starter · #15 ·
RE: Track: Derailment issues & how level does it need to be

Thanks Guys, I really appreciate your help. Sure enough, the counterwieghts are loose so I have contacted Bachmann for the replacement. Hopefully this solves my issue. I will let you know.

Regarding the derailment that took place at the Aristo #6 switch, I have noticed that when the train goes through the switch the actual plastic switch arm moves a little bit, perhaps becuase I don't have this attached to a motorized switch machine. Do you think that movement may have caused the derailment and if so would you recommend that I tape the little plastic arm in place so the track in the switch doesn't move.

Thanks for your advice
-Ted
 

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RE: Track: Derailment issues & how level does it need to be

You don't say which direction you are traveling through the switch, but in general you need a spring or motor to hold the point tight against the rail. The manual throw that comes with the Aristo switches is sufficient. If you have removed the switch throw you will have problems. If you haven't removed the manual throw, check between the diverging rail and the main rail for debris. Often a small piece of junk will prevent the switch from completely closing. I am continually removing ballast, twigs, leaves, etc. from my switches.

Chuck
 

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Posted By tcwave on 06/10/2008 9:31 PM
Hi Guys,
(SNIP)
C. Do you guys use some type of electricla solution on the wheels to help with conductivity? I notice that sometimes i will stop the train, then wait a few seconds and either restart it or change directions and the engine isn't powered up. 20-30% of the time in need to slightly move the train to get it to feel the track power.
(SNIP)
Best regards,
Ted


Ted,
CRC 2-26 has proven to be an effective solution for electrical conductivity issues between rail and engine or rolling stock pickups. Of course track will always accumulate debris and will attract a coating of dirt, tree and plant sap, and general pollution (depending on where you live) over time. These tend to build resistance on the rail surface. Some sort of abrasive cleaning may be required for the heavier, visible debris, but I agree with the previous comments against using sandpaper or anything that scratches the surface. I have used a floor Swiffer® with the pad moderately soaked with turpentine and it made short work of tree sap and other goo without any effect on plastic ties or wiring.
However I have found (and so have many others) that CRC 2-26, sprayed lightly on short sections of the rail surface and the engine wheels and all electrical pickups/axless will clean off that film and help maintain good conductivity. I like it because it is a very easy and non-labor intensive method to "fix" or prevent the problem. Just a little 2-26 sprayed judiciously as described will eventually spread around the layout and work its magic for you. :cool:" border=0>
CRC 2-26 is not always easy to find. I got mine at Home Depot but they didn't stock it very deeply; the electrical department attendant wasn't even aware of the product when I first asked. It's in a small (5 oz.)spray can wrapped in navy blue label paper with CRC's red and white logo/lettering.
Al
 
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