There has been a lot of discussion on this forum and others about the problem of Lionel magnetic couplers coming open all by themselves. Tonight, I was running a train of 22 cars behind a 2032 Alco single motor diesel. 14 of the cars are post war with metal trucks and 8 are postwar with plastic trucks. None have the low friction bearings and fast angle wheels. The car behind the loco was a long black gondola, NYC. Pulling just the cars, the front coupler came open. It did it twice after about 3 laps of the 072 oval. The 072 oval has 16 sections of 072 curved track and two 40" long straight sections. After the gondola coupler had opened up twice, I modified it using a Dremel tool with a 1/8" cutter. If you open the coupler and look on the knuckle where the pin touches it, you will see a witness mark where the pin has been rubbing up and down on the knuckle. This is where you want to make a groove in the knuckle that is parallel to the pin, or maybe I should say the groove should be parallel to the rivet that the knuckle pivots on. It takes less than 5 seconds to make the groove. Don't make the groove any deeper than absolutely necessary. If you examine the flat on the knuckle where the pin holds the knuckle closed, you will discover that the surface the pin contacts is not parallel to the pin. The pin therefore walks down due to vibration. The cattle of a 3656 operating cattle car work in a similar way. After I modified the gondola, I decided to increase the weight of the train. I put a 2032 Alco diesel dummy and a 2353 F-3 dummy behind the gondola. No problem, after several minutes, the knuckles remained closed on the gondola. Then I took the 3656 cattle car that was behind the diesel dummies, and put it ahead of them so it was immediately behind the modified gondola. As if by magic, the coupler on the cattle car opened up all by itself. I just modified the couplers on the cattle car, and now they stay closed. I think this is the solution to the couplers opening by themselves. Don't forget, you don't need to modify the plastic knuckles.
Interesting what great pulling strength you get out of your 2032. If you look at ron123's thread which is in view today, back in 2010 he had a question as to whether 5 cars or so was the best he could expect from his 2023, a very similar unit. I imagine he was running with the dummy, but still you certainly have great peformance.
The real reason I comment is that I am very interested in yr solution to the couple problem, but I am not at all able to visualize what you decribed. Some pics or sketches would certainly help me out. Thanks
servoguyDon't make the groove any deeper than absolutely necessary.
Sounds good. I have (3) 2421 series cars that will get the fix ASAP. How did you decide on the depth of the cut? Just until the knuckle tang is flat & square again? Trial & error? SWAG?
You are cutting a groove into a surface that is sloped relative to the pin and relative to the groove. The groove should be parallel to the pin, not the sloped surface, so there will be virtually no groove at the bottom of the sloped surface and more grove at the top. Top and bottom refer to top and bottom of the coupler when the car is right side up.
When you make the groove, the shaft of the cutter should be parallel to the rivet that the knucklle pivots on.
To get the 2032 to pull 22 cars, I cleaned all the oil and grease off of the track using my patented and secret method of attaching paper towels to the bottom of a gondola using rubber bands. Fold up the towels to make a pad that just touches the rails and hold them onto the gondola (or other car) with two rubber bands at the forward and aft end of the paper towels. Then add some alcohol to the paper towels to clean off the rails. This approach will also clean off the wheels as oil on the wheels will get onto the clean rails and will be removed by the paper towels. This is a better method than using a rag soaked with cleaner and wiping the rails by hand becase I get to run the train to clean the rails. Isn't running the trains what this is all about?
BTW, my 2353 with two motors pulls this train easily as does my 736 steamer with one motor.
OK, so if I've read the above correctly, the "pin" you refer to above is the spring-loaded plunger that's supposed to keep the knuckle closed, and what you're doing with the groove is making the back of the knuckle (where the plunger rests) flat and vertical (parallel to the knuckle rivet) so the plunger doesn't ride down. Do I understand it correctly?
Frank Silvia
I think you have it, Frank. I don't make the back of the knuckle "flat," I make the bottom of the groove "flat," so that the bottom of the groove is parallel to the pin when the knuckle is closed.
servoguyIf you examine the flat on the knuckle where the pin holds the knuckle closed, you will discover that the surface the pin contacts is not parallel to the pin.
Groovy hint, thank you servoguy.
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..........Wayne..........
Good grief! I didn't know the couplers were made from pot metal. The cutter grabbed and cut too far back. Next time I think I will use a grinding stone, they cut slower.
Hint: Pliers or a clamp can hold the pin down with the coupler open so it will not close while you are grooving (undercutting) the witness mark.
A grinding stone worked better for me. Instead of cutting too much in 10 micro seconds, this adjustement to the coupler took 10 seconds.
Have you tested the modified couplers?
Only with my fingers. The one I messed up longer pops open with force. Your post indicated worn couplers work their way open while running on the track (which this car did.) I'll need to put together a long train and give it a try.
This is a clever modification. I did something a bit simpler and connected the coupler parts with a rubber band used for teeth braces - it's a small loop that can easily twist about both to keep it closed.
Doug Murphy 'We few, we happy few, we band of brothers...' Henry V.
The old "rubber band fix"--rubber bands rot sooner or later, but they are easy to replace. Undercutting the "witness mark" is permenant (I would think.)* Of course if you slip, the gouge in the coupler is permenant also. in my case the "oops" did not imact operation of the coupler.
*Now that they got the lead out of pot metal, it no longer suffers "Zinc Pest." Maybe I should not call it "pot metal." The proper term is "zamak."
http://en.wikipedia.org/wiki/Zamak
http://en.wikipedia.org/wiki/Zinc_pest
I read a book a few years ago written in 1948 by a guy that had a zinc die cast business in New York City. He had figured out that even the smallest amount of lead contamination in the zinc would cause zinc pest. He even removed all the lead anchors for his machines. I don't know what Lionel uses for the die cast alloy, but it is pretty impressive. The wizards at Mercedes use pure zinc for window lift mechanisms, and they are like rubber and have no real strength. And they are heavier if than if they were made out of stamped steel. Go figure.
If you use rubber bands, the couplers no longer work. I did this modification because I wanted the couplers to work.
Wayne, It is good to see you are having success with this modification.
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