I take my hat off to the designers at Lego, who have created a model that resembles the original to such a great degree. One thing is to design just some fancy locomotive. Another matter is to design something that should be a scale model replica. But they ended up with a design hundred times more pragmatic than I thought possible.
Fig.1
It took me a lot of studying of the pictures before I detected the gross on-purpose design trick. I won’t call if «fault» since it’s to any degree done so much on purpose. This is no «crocodile» at all. It’s a small center locomotive with a wagon attached in each end. Still I forgive its designers, since it will indeed twist around in curves, and is so true to the look and feel. I even thank them, since I assume that without these approximations there would be no such model at all.
Some of these photos are shot at my partially finished My Shelf’s Railway Strip MSRS v.5.0.
Fig.2
A locomotive of type “crocodile” would have a motor unit in each end (the two round pieces have been well shown also on the Lego model, they are the ends [sides] of the two motors) making up for two end bogies or «noses». I have called them bogies here, even if I am not sure whether this is standard wording for these older locos. 
The centre box would be sitting on these bogies, and they would be hinged onto that centre box, but the bogies would also be connected to each other. The centre box would have no axles of its own, whereas this Lego loco’s centre box has two axles. The whole locomotive (or just the centre box?) thus is articulated, meaning that the loco twists around curves more or less like a crocodile. The nick-name was introduced by toy model maker Märklin for the first tin models of it, in the nineteen-thirties. This was some 15 years after the first real locos appeared on the rails. The first was a German (short) loco (EG 511-537 or DR E71.11-.37, with two axles per bogie), the second was the “real” Swiss (long) crocodile around 1920 (SBB Ce 6/8 II and III, with three axles per bogie plus a pilot axle). Both are seen as 1/32 steel models on some of these pictures. I also have some blog notes about this, see My Crocodile locomotive pages.
Fig.3
On the side of this Lego model it says Ce 6/8 II, which probably has been coined by, yes – flipping a coin – between the II and III model. See the difference in real life at 201:[II and III].
And the road number 10277, I don’t know. Some Lego numenclature?
Very much aside, since I started with trying to find out whether the starting 10 might have any relevance to the real locos. So I ended up pondering about 12 instead. This photo in Wikipedia commons, explained as «SBB Ce 6/8 II 12251 – 14283″ is called «SBB Ce 6/8II 12251″ or «Ce 6/8II Nr. 14251 aus dem Typenblatt der SLM» on the two places it’s used. Studying the picture it certainly has «12251″ on it. It may be so early that SBB had not decided on the range yet? This is the only place where I have seen 12. Except for the Märklin tinplate model 12960 (here). The smallest SBB 12xxx number I have found is 12301, here – an entirely different locomotive.
SBB Historic. Jin Chei of SBB Historic (here) as usual to the rescue. Thank you! Here is her response:
- 10277 is simply the Lego article number for the Crocodile set
- The three crocodiles Ce 6/8 II 14251, 14252, and 14253 were the first of their series. Initially, they did have the numbers 12251, 12252, and 12253. The numbering system was however changed soon (unfortunately I cannot find a proper date anywhere, but the book «Die elektrischen und Dieseltriebfahrzeuge der SBB, Band I: Baujahre 1904-1955» basically says «whoever is looking for logic or consequence in this system is looking in the wrong place» which seems a bit rough, but it seems to be true that for a while, there was a bit of a mess).
After the change, Ce locomotives received numbers starting with 14 and Be locomotives numbers starting with 12 or 13. Ce 6/8 II 14254 started out its life already with a 14-number. - (Also, if we apply that logic to the Lego number 10277, it would make it a Re or Ae 6/8 – a faster loco 😉)»
I now see that some of this is also mentioned in Zellweger 201:[12], page 156, small point 3: «bis 1920 Nr. 12251 statt 14251..» etc.
Fig.4
Some of the pictures here show the model with the Märklin 55681(of SBB Ae 6/8 III) and a model from Fine Models (EG113 / E71.13). They are 1/32 (scale 1 = 1/32, gauge 45 mm) metal replicas. The length of the Lego loco is 44.4 cm which scale-wise should be something like the length of Ce 6/8 II → 19460 mm / 444 mm ≈ 1:43. I think the width’s scale is smaller since it looks rather thin. The Lego gauge is 37.5 mm between the inner side of the rails, as explained in the Lego trains Wikipedia article – «corresponding with a circa 1:38 scale». Standard gauge is 1435 mm / 37.5 mm ≈ 38.266, which is pretty close. (The length of the Märklin 55681is the length of Ce 6/8 III → 20060 mm / 32 ≈ 62.6 cm.)
Fig.5
It’s easy to see «the gap» between the centre box and the ends. It should ideally not be there. All real crocodiles would have movements here, but only visible for those looking for caskets or the like. No free air.
JANGBRiCKS, on his YouTube channel has an episode where he describes how to fix this. See LEGO Crocodile Locomotive Easy Fixes for gaps & derailing – 10277, and about filling the gap here. The result is quite nice.
Even if the connecting rods must be placed in the correct position for the photo session, when the loco runs, it looks like, in JANGBRiCKS‘ video, that the rods follow in synchrony between each pair of wheels. I have no plans to add an electric motor for my loco, since on a grandchild’s layout I may just do as JANGBRiCKS: use a powered loco as the engine.
I think the colour of the main body is LEGO® colour reddish brown, as Lego piece 4211288, example here.
The two ends would have their inner wheels of a type that does not have any flanges. Peculiar, but I assume it’s to avoid having flanged wheels too close to each other? But this also is one of the points that it takes a while to discover.
The electrical installation on the roof works to me! The pantographs even have isolators. This certainly is electric’ish! One can have fun for a long time digging into the details and looking back to see what they resemble. Well done, Lego designers!
Fig.6
You will find the building instructions of the Lego 12077 here. The instruction PDF is here and the booklet PDF is here. Item 4308468, whatever that means. Lego set 10277. Year 2020. Add Lego hub 88009 and Lego Technic motor 88013 and LEGO® Powered Up app and you can run it around your layout. But be aware of dematerialising bricks, they will never appear before your eyes again. Since..
..the completed model is quite fragile. Pulling the two ends apart from the centre unit and then carrying three friendly pieces is perhaps better than an alive crocodile that tries its best to escape my rather uncertain grip. 1271 pieces scattered on the floor, instead of them coming from numbered plastic bags, do forbid. It is certainly possible to lift the model by the track stand, but the feeling that it creaks at the joints feels evident. For the somewhat permanent placement inside my wardrobe (fig.2 and fig.3) I took a nylon fishing line and a spring underneath, to hold the track stand down at the ends. If not, 2-3 mm raise at each end wasn’t that nice. (If anybody at your work work would ever throw a defect copy of a Luxo or Anglepoise type lamp, make sure you pick out the springs. [If it’s a real one, snatch the whole lamp and fix it!] The springs are ok to keep. Keeping a closet door open shows an example.)
Fig.7
Observe that if you buy this online and you are in the EU or EEA then you can pay VAT to the foreign net shop and not have to pay VAT to your own country. This is called a VOEC number (Wikipedia). Observe that if you buy from Norway, to get this to work, read the Wikipedia link for what you have to ensure that the foreign internet shop must have done. This makes it cheaper, because else you would have to pay the local VAT, plus a fee for the customs work.
The set is labeled age 18+. To use or to enjoy, perhaps. (And to lift?) But my middle-aged team of grandchildren here, aged 7, 9 and 12 (average fast approaching 10+) (the two year kid wasn’t invited to the building session, and the 14 years was, politely, not interested) built the unit as a team, managed by a mild team leader (me), in three to four hours, including a jolly lunch. 
Thank you, Linnéa, Filip and Jakob!
The building scheme went like this. The single one doing the actual building sat in that particular chair, while the two others helped reading the building instructions and finding the right pieces. After some time the builder in charge got tired, for real, and thus actually fancied a break. And I overlooked it all, and made agreements in advance that perhaps after the next page of the manual, or the next, was the time to swap the builder.
Thank you, all the family (now adult) relatives here in Trondheim, who gave me this lovely kit as a summer gift! That I did (and continue to) enjoy, is putting it mildly.