Ub sleeping car ACME

Ub sleeping car

Anonymous photo, coll. P.-Yves Toussirot in Trains d’exception, Éditions LR Presse 2022.

ACME 51021


Ub sleeping car, ex YTb EIC 1950

UIC Number (DB) ex-CIWL Rev. date
71 80 71-40 648-9 3957 5.5.72

140 g (NEM: 108 to 140 g)

The overall scale is respected, except for the height and the wheel diameter. Apparently it was difficult to reconcile these two dimensions.

Many parts remain to be assembled:

  • in metal, small steps, marking plates (for the latter, the fact that they are not mounted from the beginning has an explanation: they limit the bogie pivoting);
  • in plastic, jumpers, mooring rings, all difficult to fit. For the rings, there is no housing provided, and they are impossible to fit in certain positions as described in the instructions.

The underside of the chassis is detailed, with plastic and metal linkage. The dynamo is fixed and its belt hinders the movement of the corresponding bogie. Other brands have been able to make a pivoting dynamo.

The running is good, despite the presence of current pickup strips! How can this little miracle be explained? Well, very simply: they don’t touch the axle shafts, and are therefore useless!

The bogies have real suspension springs, which are not functional of course, but which tend not to stay straight. There are also metal anti-fall hoops. Beware: some of them don’t hold, they have to be glued back on. The wheel back-to-back distance ranges from 14.2 to 14.3 mm, which is insufficient according to NEM (14.5 ± 0.1). The flanges are 0.8 mm.

Folded bellows are included in the parts bag, but the mounted bellows are almost impossible to remove… In any case, I didn’t succeed.

The interior is uniformly light brown, with a touch of silver paint on the door handles. The ladders are correctly positioned. Some grey blinds are more or less down on the compartment side.



To improve the running in curve, down to R 500 mm, while keeping the end marking plates in place, milling of a bogie side beam, 1 mm in width and height, at an angle of about 12°. See photo.Milling of the bogie

Max. rotation before milling. After milling.Bogie rotation before millingBogie rotation after milling

Note that the dynamo belt had to be shortened so as not to interfere with the bogie rotation.

This coach belongs to the YTb series CIWL No. 3933 to 3962 built in 1950 by Entreprises Industrielles Charentaises (EIC) at Aytré. In the 1960s, the CIWL workshops at Saint-Denis near Paris converted ten of these coaches into Ub, and removed an access platform, similarly to the Breda dining cars. These are Nos. 3949, 51 to 55, 57, 58, 60, 62 (Source: Trains d'exception by J.-Marc Dupuy and P.-Yves Toussirot, Éditions LR Presse 2022).


  • The coach pictured, no. 3832 (Nivelles 1941), from the TEN pool, SNCF manage­ment, is of the same type and has under­gone the same transformations. It is seen at the Ourcq maintenance, in March 1978, from the removed platform end. It has been fitted with UIC rubber joints.
  • The name YTb referred to coaches with eleven compartments, seven of which were double and four were triple.
  • In the Ub designation, the U stands for Universal, i.e. each compartment can be fitted out for one (single), two (double) or three (triple) passengers. The b means that the interior partitions were originally made of wood, although they were later replaced, usually by laminate.


ACME Ub sleeping carACME Ub sleeping car

ACME Ub sleeping carACME Ub sleeping car

Ub sleeping car

Anonymous photo, coll. P.-Yves Toussirot in Trains d’exception, Éditions LR Presse 2022.

23 450 270.0 270.0
22 200 255.2 256.0
2 822 32.4 32.6
4 005 46.0 46.6
16 000 184.0 184.0
(PPs) 2 500 28.7 28.8
1 050 12.1 11.0