Hi everyone. I thought it would be fun to buy a small Bachmann N scale train set and set it up in my office. I keep having some issues however that are frustrating, one of which is my cars and engines decouple for no reason. I bought a bunch of knuckle coupler cars on eBay, and added a second identical loco from Bachmann. Most of the time things work fine, however periodically cars uncouple for no reason. I turn the car around and sometimes this fixes it. Sometimes I put the car in a different order in my train. Sometimes this fixes it. I have one loco going backwards coupled to the second loco in front. This worked fine for the first few weeks, then the locos started uncoupling. I have about 16 cars in my train going around an elevated figure eight E-Z track. So I turned the second loco around and it seems to be working. I even have cars that were together in the original train set uncouple. It just seems to me that this technology is not up to snuff and is highly temperamental and finicky. Am I doing something wrong here? I can't imagine having these problems on a large scale layout. Thanks.
Couplers do require maintenance , 75 % of the time its coupler height that causes issues. Assuming you've checked this , you need to look for other possible causes like excessive vertical play, warpage , damaged springs , track work , ect.
In N scale couplers are plastic , so warpage could be a problem . Also any problem gets magnified X2 compared to HO and in HO the couplers (KDs) are metal so coupler warpage isn't so much an issue .
The other problem is coupler bounce . If the couplers are bouncing horizontally , they can uncouple . This is usually caused by a couple of issues :
1. dirty track or dirty locomotive wheels , the lead loco hesitates slightly allowing the train to catch up , pushing the knuckles open , if the couplers are not in perfect working order , the knuckle can stick open just long enough to decouple , This is especially true with locomotives , sometimes its easier to use dummy couplers or draw bars between the locomotives. Just cleaning the track or loco wheels may solve your problem .
2. After the cars have "run in" , the cars become more free rolling and on down grades they can catch up , and push the knuckles open . Cabooses are some what notorious for this and at times seem to have a mind of their own .
If knuckles are sticking , then it may be neccessary to lubricate them , don't use oil, As I remember dry lubricant(Labelle 134) is what you should use , but check with Micro Trains first. If the uncoupling bar is corroded then you probably just need to replace.