After a way too long hiatus from the workbench, I was downstairs the other evening building a few boxcars from some floors given to me by my friend Dave. I had somehow acquired several boxcar bodies w/o floors so he graciously gave me some extras he had.
All went well until I railed the trucks and saw that the couplers were too low. But on closer inspection, I realized that the back of the coupler was fine; it was the front that was hanging down. Digging even more deeply, I realized that the coupler pocket was either too deep or the coupler shank was too thin.
I remedied this with a small piece of plastic under (green in above illustration) the shank in the front of the coupler pocket but it does point out a problem that I've faced from time to time. These measurements are STRICTLY guesstimates but they should illustrate the issue clearly. Let's say that the coupler shank is... .10 inches thick. And the coupler pocket is .15 inches deep. When the couple is properly assembled in the picket, the front of it will hang down.
In my case, I remedied this by adding a small piece of plastic in the front bottom of the pocket to raise the coupler's head but I've also read where you can use a trimmed Kadee fiber washer in the pocket to raise the head as well.
Good to know...