Uncoupling

I've planned to equip all my cars with Kadee couplers, because of the improved operation. Kadees will couple much more gently than Atlas couplers, which generally take a moderate slam. Kadees are also much easier to uncouple than Atlas couplers. I loath uncoupling magnets - they're never where you need to uncouple, except on rare occasions. If you do uncouple over one, you either leave the car with it's coupler sprung to the side so you can't couple to it, or you have to back and fill to shove the car back past the magnet. And of course they always seem to show up under spots where you stopped without intending to uncouple. I prefer to uncouple with a skewer like tool.

At the recent Springfield, MA train show Kadee displayed their new O scale couplers for the first time. My first thought was "Aha! My procrastination has paid off!" So I bought a couple pairs of the #745 "prototype" head medium centerset shank metal couplers with plastic boxes. Previously I'd used only #805 metal couplers in the metal boxes. I was pleasantly impressed at how easy it was to prepare a metal coupler in a plastic box - none of the filing and burnishing I'd done on the metal in metal ones appears to be necessary. And the #745 couplers look nicer than the #805s.

The real test came when the couplers were on the cars and in operation. The #745 couplers coupled very easily - pushing a car along at under 1 scale mile per hour to couple up to a lone free standing car still resulted in the knuckles sliding past each other and coupling, instead of just pushing the free standing car down the track on the coupler face like the Atlas couplers do.

Uncoupling was a different story. Here's the two different couplers, coupled and under slight tension for comparison. Click on the photos to see a larger version.

Kadee #745 couplers coupled

Kadee #805 coupled

You can see that there is a lot more open space between the 805s. The 745s still have a little, but they're definitely tighter.

Here's my arsenal of uncoupling tools.

Uncoupling tools - best are center, and right.

On the left is the Micro-Mark tool. Some people seem to like it, but for me it just doesn't work for O scale couplers at all. Second is the Accumate Switchman, which doesn't seem to be nearly as useful as I'd hoped but it does work up to a point. Then we have a narrow skewer that works well for HO kadees, a slightly thicker skewer with a screwdriver like tip carved into the end opposite the point - my current go to tool for O scale since with the mixture of couplers I have I need both ends. The next tool is the same size skewer as the center favorite, but shoved into the carcass of a bic pen after pulling the ink cartridge out. The idea being that you can put it in your pocket without stabbing yourself (with the cap on), but still have enough point to uncouple. I have to admit it falls into the category of nice idea but doesn't work as well as I hoped. Second from the right is an extra large skewer, and finally on the left is the classic #2 uncoupling tool, which can also be used to take notes, mark up switch lists, etc.

The first technique I tried to uncouple the #745 Kadees was the classic - get slack, drop the skewer in the hole in the middle, and twist. That does not work, since the knuckle has a squarer corner which fits more perfectly into a squarer opening. The result is putting the skewer in the middle wedges the knuckles into the couplers, the knuckles can't open far enough to get by either the skewer or each other, and you're stuck.

745 knuckle wedgie

In order to uncouple the 745s you need to have just the right amount of slack - either tension or compression makes it nearly impossible. The screwdriver tip end on the medium skewer tool then works pretty well. But since the opening you're aiming for with it is pretty small, it's pretty hard to uncouple on a rear track (my rearmost track is about 26" from the aisle). Uncoupling on a curve is slightly harder, again because of the tighter fit.

Here's the same uncoupling tool (the center skewer from the above photo) in a pair of 805s.

805 knuckles not wedged

Notice how much bigger the hole between the knuckles is than the 745s - much easier to get the tool in there on a rear track. Also the knuckles don't get wedged, and you can twist to uncouple even if the couplers are under compression. The medium sized skewer will just sit in the knuckle once you twist it open, and you can leave it there while you pull away.

After the twist

The twist open technique doesn't work as well with a Kadee coupled to an Atlas, and it doesn't seem to work worth beans with two Atlas couplers. But in both those cases you can use an alternate technique that requires slightly more careful aim of sliding the skewer in at the knuckle tip as shown in the "after the twist" photo about, skipping the twist step. There is a certain middle aged vintage of Atlas couplers for which that technique doesn't work at all though, which is why I have the screwdriver tip carved in the other end of that skewer.

If you operate with switch lists you're familiar with the need to mark them up and scribble notes. Currently I'm using car cards, but I have done some sessions with hand written switch lists and I hope to eventually get computer generated switch lists working. The point is, you need a pencil anyway, and with Kadee 805 couplers a pencil is also an effective uncoupling tool, using the same drop in the hole and twist method as the skewer. The only difference is the pencil won't stand in the open coupler by itself like the skewer will.

#2 uncoupling tool in action

The bottom line is I like everything about the new Kadee O scale couplers except the way they uncouple. But that is important enough to me that I'm going to stick with the old 805 couplers. However I am sold on the metal coupler in the plastic box, so I've ordered enough of the #817 plastic box sets to cover the rest of the 805 packets I have on hand.