A little bit of progress to report but no photos yet...
I've been working on the link bar design - I find sketching ideas out on a note pad, a skill I learnt back at A-level design - really useful. I've gone for 5mm brass tube from Eileen's Emporium - this will have at one end an circular hole to take a pin, and then Roll-wagen will have two 120thou plasticard mountings that the bar slips between and is pinned into...
At the second end, the one that attaches to the other stock, I've gone for a sort of clip. It's going to be made from brass (0.5mm thick 5mm strip is my starting point) and will clip over the buffer. This will make it easy to fit and allow it to be pushed or pulled - and also no modification to the wagon. This also makes it look more prototypical, as in the prototype it would go through a hole in the centre of the buffer for this link and pin arrangement.
I hope to make a start on it this week.
I've also started looking at detailing the bogies with brake shoes and fake spring detail - and adding some brake cylinders and pipe runs to the chassis - this needs working out properly but I've got firm ideas on what to use for the various parts, just need to work out how they work in reality so it sort of makes sense on the model.
In other news - Mike (dutchelm) has helped out (again) with supplying some parts for the steel bodied brake van - a chassis and a roof mainly. I already have the glazing for this, and have ordered the last of the plasticard I need to do the bodywork. That will start when the Roll-wagen is finished