# Sticky link couplers



## flyernut (Oct 31, 2010)

The #1 reason link couplers cause so many problems is that they tend to stick in the up-right or uncouple position.. I know the first thing we all do is to get out the hair-dryer or heat gun and remove the plastic mold release agent found on the couplers, and then oil them...That works in most cases but what do you do when it just doesn't work??.. Well, here's what I do..I been working on my problem boxcars/reefers for the past several nights because of the sticky couplers.. I remove the pins by using a cut-off wheel in my dremel. You have to be careful because you will build up some heat, hot enough to melt the plastic coupler, and you will be using that coupler again.After I get the coupler off and the pin removed from the truck tongue, I put on a small dab of flat black paint where you cut off the pin as you're always going to have a few marks on the tongue where the cut-off wheel hits. I run a rolled up piece of sandpaper through the hole in the coupler, and also on all sides of the coupler. I clean it all off with some rubbing alcohol, (I use spearmint scent). I then try a pin in the coupler hole to be sure it swings free, and I also try the pin in the truck coupler tongue..If everything is good and free, I'll put on a small dab of oil in the hole of the link coupler and install the coupler and pin on the truck tongue..I then set the coupler height using a known to me original car with original couplers..Yes I know this isn't rocket science, and I was getting frustrated with uncoupling cars so I decided to do something about it. And besides, when I give all my trains away to my kids and grandchildren, I want them to be in perfect running order so they can play with them without any problems.. Here's some pix of 2 of my Hudsons pulling a few cars that I have repaired..sorry about the dirty lay-out, it is what it is......


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## mopac (Feb 24, 2011)

Thanks for the tip flyernut. Cars uncoupling is a pain in the butt. Instead of cutting the pin I bought
me a pin removing tool. I think the pin is reusable. We shall see. Reaming coupler hole some is a
good idea. Your layout does not look messy to me. Link couplers are not my favorite. I would like
knuckle on everything.


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## flyernut (Oct 31, 2010)

mopac said:


> Thanks for the tip flyernut. Cars uncoupling is a pain in the butt. Instead of cutting the pin I bought
> me a pin removing tool. I think the pin is reusable. We shall see. Reaming coupler hole some is a
> good idea. Your layout does not look messy to me. Link couplers are not my favorite. I would like
> knuckle on everything.


Be careful trying to use a used pin, they just don't work.. Once they have been "swagged" you can't get them back into the truck tongue hole.


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## AmFlyer (Mar 16, 2012)

For sticky couplers, I drive out the pin using the link coupler tools. Then carefully clean the coupler and test it for free rotation on a new pin. After cleaning they all have proven to rotate freely. I then put it back on the car using a new pin and the link coupler tools. So far it has worked. I prefer link couplers for three reasons. One, they will couple at very slow speeds, two, they will couple on any curve, three, the cars couple closer together than with the knuckle couplers. I hate them because they are hard to get correctly adjusted so the cars will not spontaneously uncouple.


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## TimmyD (Dec 6, 2021)

Hi all! I am also struggling with uncoupling cars. I will be getting some new pins so that I have the option to properly remove, clean. and re-swage when necessary. However I am also referencing Mr. Barker's book; and he recommends hair dryer followed by Super Slick Slick Stuff. Have any of you tried this method and had any success? From a sheer time invested standpoint, I feel like it would be worth it for me to try this method first, and then replace pins on trucks that remain problematic after this treatment. Any thoughts? Thanks as always and happy new year to all!
TimmyD


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## AmFlyer (Mar 16, 2012)

The hair dryer is a time proven way to get off the mold release agent that usually shows as a white substance on the plastic. It might free up the coupler. I have sprayed contact cleaner inside the coupler hole as well. Sometimes it helps. I do not know the Super Slick stuff but if Barker recommends it give it a try.
For me the corrective action is just personal time management. Some couplers are loose and wobble, some are tight and stick. With the tools It takes less than 5 minutes/coupler regardless of the problem and the fix is 100% certain. The other methods also can work, but in my experience not 100% of the time and I still need to replace the ones that are too loose.


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## TimmyD (Dec 6, 2021)

AmFlyer said:


> The hair dryer is a time proven way to get off the mold release agent that usually shows as a white substance on the plastic. It might free up the coupler. I have sprayed contact cleaner inside the coupler hole as well. Sometimes it helps. I do not know the Super Slick stuff but if Barker recommends it give it a try.
> For me the corrective action is just personal time management. Some couplers are loose and wobble, some are tight and stick. With the tools It takes less than 5 minutes/coupler regardless of the problem and the fix is 100% certain. The other methods also can work, but in my experience not 100% of the time and I still need to replace the ones that are too loose.


Thanks Tom!
I have only replaced one link coupler so far, and all of my tooling was improvised, including using a center punch in several locations around the pin to re-swage the existing pin, it took a long time and was imperfect to say the least... I will be putting in an order with port lines shortly which will include a coupler tool kit and some pins, but I guess I expected the factory assembly would likely be better than one I had messed with, and I imagine the process will likely take me a lot longer than 5 minutes. On my next pin replacement, I would like to either dremel or file some of the old swage off, as I did bugger up the mounting hole on my truck a little on the one I have done. I'll give the super slick slick stuff a go and report back. I am sure replacing the pins is ultimately a better option, if done correctly, which I am still learning. 
Take care and happy new year!
TimmyD


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## AmFlyer (Mar 16, 2012)

The right tools and backing/jig make a major difference. Flyernut made a jig fixture to hold the truck and coupler while he is driving out pins and swaging new pins. I use a small anvil that has the right shape but I still need to hold the truck in position, unlike with Flyernuts holding fixture. He does A LOT more repairs than I do.
Another reason I prefer to take off marginally working couplers is to make it easier to completely adjust the coupler arm to the correct height with accurate bends. The coupler arms can be surprisingly distorted over decades of operation and bad adjustments by previous owners. On some cars I like to back cut (file) the couplers so they grip the pin on the mating coupler tighter. 
It takes a lot of careful adjustment to be able to run 20 link coupler car trains around a layout including up and down grades.


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## flyernut (Oct 31, 2010)

Here are the steps I take for sticky link couplers in the order of trying..First, I use my heat gun and remove all the release agent, and work that coupler up and down for like a gazillion times. If that doesn't satisfy me, a squirt of oil like 3 in 1 and again work the coupler a gazillion times.. If those 2 actions fail me, off comes the pin, and a new pin is used. Like Tom, I make sure the coupler spins freely on the new pin. What I also do is to sand the pin hole in the coupler using a rolled up piece of 400 grit paper. That mold release agent will get into that hole, and I take the time to sand it off to remove it. I also sand the sides of the coupler making sure all the gunk is cleaned off..Like everything else in life, the proper tools go a long way in repairing objects, not just trains but everything.. After this last repair I haven't had any issues whatsoever with uncoupling, and I think I mentioned in another post I'm pulling upwards of 9-11 boxcars, (642), with one of my Hudsons.. Someone else may have a better solution but my way works for me, just saying..Loren


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## TimmyD (Dec 6, 2021)

One more question on the link couplers... I seem to have a few that are running at different heights than others, which is at least contributing to my coupling and staying coupled issues. I have not found a proper height adjustment in the literature available to me for the link couplers, only for the knuckle couplers, but I guess since they function with the same uncouplers, it is likely the same? Just wondering, along with the freeing up any friction between pin and coupler, making sure that the top of the coupler is flat and level, and assuring proper wheel gauging, do any of you have a good trick or spec for how high above the track the weight should sit? I don't want to arbitrarily pick a car and adjust them all to that if there is a spec. Also, am I missing any other important factors? I qualitatively check drag of each individual car when I am railing them.
Thanks as always!
TimmyD


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## flyernut (Oct 31, 2010)

TimmyD said:


> One more question on the link couplers... I seem to have a few that are running at different heights than others, which is at least contributing to my coupling and staying coupled issues. I have not found a proper height adjustment in the literature available to me for the link couplers, only for the knuckle couplers, but I guess since they function with the same uncouplers, it is likely the same? Just wondering, along with the freeing up any friction between pin and coupler, making sure that the top of the coupler is flat and level, and assuring proper wheel gauging, do any of you have a good trick or spec for how high above the track the weight should sit? I don't want to arbitrarily pick a car and adjust them all to that if there is a spec. Also, am I missing any other important factors? I qualitatively check drag of each individual car when I am railing them.
> Thanks as always!
> TimmyD


I just make sure the coupler is parallel to the track rail.


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## AmFlyer (Mar 16, 2012)

The answer to this question is more complicated than usual. There is no single right way to set the couplers, I adjust mine differently than Flyernut, both ways work. 
The criteria is 1. the tip of the coupler must be high enough to ride up over the pin when coupling. 2. the coupler weights when cars are coupled together must not drag on turnout rails or rerailers but must be low enough that the uncouplers can lift the links high enough to uncouple. Between 1/32 and 1/16 above the turnout point rails is high enough for the weights when the couplers are coupled together. 3. all couplers must be adjusted the same. 4. I prefer the coupler tip have a slight droop, but still meet criteria #1. To me this seems to give a more resilient attachment when the cars are coupled. It is ok for the coupler to slightly drag on turnouts and rerailers when it is not coupled to another car. 5. The pins must be horizontal, not leaning up or down, or angled to the front or back.
Sometimes despite all efforts to set a coupler perfect, a car will still randomly uncouple. Usually this is a trackwork problem but the coupler solution is to file back the vertical edge of the coupler to create an inward angle. This will prevent uncoupling when the two couplers are in tension. It also makes uncoupling a bit tricky, the engine must be slowed to put slack in the coupler when the uncoupler button is pushed.


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## TimmyD (Dec 6, 2021)

Thanks Flyernut and Tom, I appreciate the help. I do hope to minimize my uncoupling issues and think I can likely correct a lot of my uncoupling issues with the guidance you have provided. A fair amount of it is also likely track inconsistencies as I am using stock AF track laid on floor with no mounting other than track clips where needed. I think the temporary layouts are fun and have no room for a permanent layout, but they also make consistently precise track challenging! All the rolling stock will be getting a little attention, and will get rolled over a switch as well when testing. Thanks again!
TimmyD


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## AmFlyer (Mar 16, 2012)

TimmyD, you are right. Gilbert track loose on the floor can cause uncoupling problems. That is why I use the SHS/MTH track for floor layouts, the roadbed locks together to keep the track aligned. Plus it comes in larger radii. Putting the Gilbert track in rubber roadbed will help.


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