Well...three actually, and four if you count the Z scale coupler that is pictured in comparison. But I'm getting ahead of myself.
First, it is confession time. I am not a big fan of Micro Trains couplers. I'm not a really big fan of their trucks, either, but I like the trucks better than the couplers. Except for the six axle passenger car trucks. I hate those things, always dropping wheels, and the exploding couplers, don't even get me started...
But back to couplers. Micro Trains uses a two piece coupler design with a spring in the middle to provide a delayed uncoupling action. Some of the designs are meant to replace the T shank Rapido couplers, and if the standard design is a PITA to put together the T shank designs are something altogether different.
You can buy all Micro Trains couplers in kit form, which just adds to the aggravation (the price break advantage pales considerably with every spring that flies off into the null space between universes, never to be seen again), and some assembled, which adds to the price but in the long run is worth the extra charge. Some couplers do not have pre-assembled versions, most notably the T shank designs, so assembly is required. To add to the fun of the T shank design, most of them cannot be assembled off of the model and can't make use of the assembly jig.
The assembled versions also have a very annoying habit of coming to pieces at inopportune times, most notably their talgo truck designs (for non model railroaders, talgo trucks have the couplers mounted on arms off of one end of the truck). I can't count the number of times a trip pin has caught on a piece of clothing and popped the lid off the draft box. You may be able to recover the coupler halves, but that spring is nestled up to your missing socks and 10mm sockets. The body mount designs, once they are mounted, have the mounting screw to hold them together but everything else needs to be touched in strategic areas with a hot soldering iron tip to keep them together. On top of all that purists will point out their unrealistic size, although to be fair the standard N scale couplers from all the manufacturers share that particular flaw; some are worse in this regard than others, but all of them are oversize.
One thing that all Micro Trains couplers do, regardless of their design, is bounce. This is extremely annoying as you watch your train run down the track at switching speeds, the cars bounce back and forth as if they are connected with pogo sticks instead of couplers. Unfortunately this design flaw is carried over into the Z scale line as well, so fitting Z scale couplers to your rolling stock to provide a more realistic size doesn't eliminate the bounce.
Couplers from other manufacturers don't bounce. Atlas's Accumate couplers, the couplers found on BLI cars, and the McHenry style EZ Mate from Bachmann will all play fairly well with each other and have no bounce. Unfortunately the Accumate is difficult to retrofit onto cars not originally equipped with them, BLI does not offer their couplers separately, and the EZ Mate, although it will fit into Micro Trains draft boxes as if they were designed to do so, are even more oversized than the rest and have excessively long shanks (to fit EZ Mate couplers into Micro Trains 1015 or 1016 boxes, use their short shank and medium shank respectively in place of Micro Trains medium and long shank designs). Additionally, using the EZ Mate means you have to buy two couplers to make one, and that can get expensive in a big hurry.
But, for all their flaws Micro Trains followed the old Texas Ranger motto and got there firstest with the mostest, so they are the industry standard for better or for worse. Most of us use the Micro Trains couplers because they make a coupler style or conversion kit to fit almost every car and locomotive ever made in N scale, and if all else fails you can always glue on a piece of strip plastic for a body mount coupler.
Micro Trains has not been completely tone-deaf however. A few years ago they released a new design of coupler called the True-Scale. I recently purchased some of them to see how they stack up.
First off, they only come in kit form, not pre-assembled. However, instead of the disappearing spring, each coupler half is fitted with a whisker that provides the coupling action (uncoupling has to be done with a tool, no provision is included for automatic uncoupling). This makes them extremely easy to assemble. The following pictures shows the assembly process:
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| The parts. Note the absence of coil springs, the whiskers on the ends of the coupler halves serve that purpose. |
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| First the lower coupler half is positioned over the mounting stud |
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| and then the upper half. |
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| The coupler box lid is then pressed into place, and just like that the coupler assembly is complete. |
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| Flipping the completed coupler assembly over reveals the mounting hole for the brake hose. |
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| Actually fitting this hose is optional, it does nothing for the operation of the coupler and is there strictly for appearances. |
Assembly was so very easy, in fact, that I found myself becoming quite annoyed that Micro Trains hasn't seen fit to redesign the rest of their couplers along these lines. Not only is the assembly very easy, but since the coupler halves have a fixed pivot point the bounce is completely eliminated. Also, true to their name, the size is close enough to scale (smaller than even the Z scale coupler) to make purists smile.
Another good thing is the True Scale couplers are a drop-in replacement for the Micro Trains 1015 or 1016 coupler that is used in many body mount applications. The 1300 short shank True Scale is used to replace the 1015 and the long shank 1301 True Scale is used to replace the 1016. Many diesel locomotives made by Atlas, Life-Like, Kato and increasingly Bachmann, also use this size and style of coupler draft boxes if not the entire coupler, so retrofitting those locomotives is a snap. If your rolling stock came equipped with body mounted couplers there is a very good chance one of these will be a drop in replacement, and if not they are as easy to body mount as the 1015/1016.
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| The true-scale couplers comes as either long or short shank. |
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| A size comparison. The top couplers are a Bachmann medium shank EZ Mate fitted to a Micro Trains 1016 draft box on the left and a Z scale coupler on the right. The middle couplers are the long shank True Scale on the left and the short shank True Scale on the right. The bottom couplers are the standard N scale Micro Trains 1016 on the left and 1015 on the right. Note the size difference between the N scale EZ Mate at the top left and the N scale Micro Trains 1016 on the bottom left. Also notice the size difference between the Z scale coupler on the top right and the True Scale couplers in the middle. |
And now for the disadvantages.
First off is their size. They are small. Smaller even than the Z scale couplers, as I mentioned before and as clearly visible in the picture above. What that means is they will not couple with any other coupler, either N or Z, by any manufacturer. This means you either have to convert your entire fleet at once, made more difficult by the fact that there are only two offerings (short and long shank, both body mounted) so converting most cars is going to mean body mounting, or you are going to have to make conversion cars to use as you convert your fleet slowly. That's not such a big deal to those of us who started out with Rapido couplers, but anyone that is new-ish to the hobby will likely find this very annoying.
A comparison of size mounted on cabooses. The caboose on the left has the standard size N scale Micro Trains coupler, the one in the middle is the True Scale coupler. The caboose on the right is Nn3, fitted with a Micro Trains Z scale coupler. This difference in horizontal dimensions is great enough to prevent the use of True Scale couplers with either N standard or Nn3/Z scale couplers.
The second issue is their size. Not only is the coupler smaller in the horizontal dimensions, it is also smaller in the vertical dimension (this is called "gather" and refers to the dimension of the coupler face). The reduced gather means there is little to no wiggle room for mounting height, you will have to make certain the coupler is mounted to exactly the right height as measured by the Micro Trains height gauge or there is a high likelihood the couplers will not couple.
A side shot of the previously pictured cabooses showing the difference in gather between the standard, True Scale, and Z scale couplers. 
This photo is a better illustration of the gather size difference between the standard N scale coupler on the left and the True Scale coupler on the right. 
Although closer, it is apparent that the gather of the Z scale coupler on the left is also bigger than that of the True Scale coupler on the right.
Another disadvantage to the reduced gather is that the coupler does not tolerate sloppy track work. While we should all strive to be perfect in our track work to improve the running qualities of our railroads, in the real world we are not all skilled enough to get every level perfect and every grade transition flawless. The True Scale coupler demands both.
A third issue is their size. Because the shanks are so much shorter the coupler swing, the angle it can deviate from centerline, is greatly reduced. And, since they are all body mounted, this means that tight curves will cause freight cars to be on the ground instead of on the rails. So in addition to the tight tolerances in vertical variation required, larger radius curves are also a must-have.
So far I have one locomotive, a handful of freight cars and a caboose converted to the True Scale couplers. I have adjusted heights to match perfectly, but my trackwork is not pristine enough to ensure flawless operation. I am happy to report that Kato Unitrack assembled on a flat surface is sufficient to run this train, however, and I am pleased with the results. No bounce, closer coupling (not a good thing on tight curves but it looks great on the straights), and more prototypical size.
Since my current layout uses curves tight enough to derail body mounted couplers (especially these body mounted couplers) and has vertical variations in excess of their gather (meaning, great enough to cause them to uncouple by lifting one over the other) this train will not see service on my home layout. I am almost positive that vertical variations will limit their use on show or club layouts as well, T-TRAK and N-Trak layouts often have large enough vertical variations at the module joins to cause problems on standard size N scale couplers so these will never work. When I build the next version of my home layout I will pay closer attention to my trackwork and use bigger curves, so hopefully they will work there.
In the meantime, they sure do look great on my display shelf!
