Recently Hornby have released their 6 wheeled Sentinel in the guise of L81 which represents the first of three Sentinel's acquired second hand to replace the venerable LT Pannier tanks.

Unfortunately with the prototypes their wheelbase was insufficient to operate track circuits on the main line. To address this a tender was attached fitted with a trip cock. 

The tenders were manufactured from 'Q' stock bogies. The tender and Sentinel carried conventional coupling gear as well as Ward-Lock couplings.  This allowed the shunting of other Underground stock. 

Difficulties in fitting the Ward-Lock couplings made fitting of normal buffers to the Sentinel's problematic. To address this wooden buffers we're fitted to the Sentinel's front end with a Ward-Lock coupling.

The tenders were able to accommodate Ward-Lock couplings as well as standard hinged oval buffers. 

CDC Kits have come to the rescue with a 3D printed tender. A choice of buffer positions are available.

https://www.ebay.co.uk/itm/225753447991?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=0CsmXNqgQWK&sssrc=4429486&ssuid=MNMqJGNPSxi&var=&widget_ver=artemis&media=COPY

I chose the buffers down version. On arrival other than paint and couplings the kit is ready to go. Unless...

If you look at prototype pictures of these tenders coupled to the Sentinel's you will see tender runs at the same height as the Sentinel's buffer beam.

The CDC kit is supplied running on 12mm Dapol wagon wheels. This then gives a stepped appearance between tender/Sentinel.

To address this holes were drilled out for brass axle bearings. Then Gibson 10mm Lowmac were fitted which lowers the ride height of the tender correcting it.

In using tension lock couplings, lowering the tender then ensures coupling height is the same as the representation of the Ward-Lock coupling housings on the tender. 

As you can see from the photo below markings have been set out for drilling holes for Bachmann NEM fitting tension locks.

Finer handrails will be soldered up for the tender as well to match the Sentinel. 

Livery wise on the prototype the tender was finished in black with a red buffer beam, white handrails and collector shoes. 

More soon once I've fired up the soldering iron.

Cheers,

Mark