This looks very good and I think the Silhouette cutter works better with card than with plasticard, where it can only cut very thin sheet.  Your roof moulding is a real tour de force

I wrote about the Dean clasp brake at  https://www.rmweb.co.uk/blogs/entry/19076-broad-gauge-mail-coach-part-5/   The important thing to recognise is that the pivots work in two planes.

5 hours ago, Dave John said:

these subtle roof shapes are so difficult to get right

Thanks Dave for your kind comments - much appreciated.  Yes, the GWR (like other companies) seem to have employed subtle roof shapes and in some variety, so one former will do horseboxes in the early diagrams but later diagrams will need another - thankfully, the formers don't actually take very long to make as the arcs are in a single plane.  Much more difficult would be, for instance, the American style MET coaching stock with the ends rounded in both longitudinal and transverse directions.  The overall roof thickness at just under 1mm would, I think, make the system viable for 4mm scale.

2 hours ago, MikeOxon said:

I wrote about the Dean clasp brake

Many thanks Mike for your comments and for taking time to find and post your reference to earlier research which I've looked hard at and I think I've understood!  It looks as if I'm on the right track in the above diagram but there are a couple of things which I'm not so clear about. The first is the connection between the pull rod worked by the vacuum/hand lever and the outer lever arm on which the brake block sits (A to C in my diagram).  If I've understood your illustration correctly, you have the pull rod connected to a crank on the lever arm.  There is a drawing of a diagram 25 6 wheel fish wagon on page 38 of Russell's Great Western Coaches part one: unusually, the drawing actually shows the brake rigging.  It looks from that drawing as if the pull rod is attached directly to the lever arm without a crank.  I've scanned that bit of the drawing (and I hope not offended copyright - if I have, I'll delete it).  The other end shows the same thing but with the pull rod rising to the same position relative to the wheel. It's this piece of reference which determined the point of connection between pull rod and lever arm in my diagram. The other thing I wasn't sure about is whether there is a single pull rod reaching to each brake set or whether there are two - one left and one right: again from Russell, it looks as if there might be a pair so each wheel is braked by its own pull rod.  I'd be interested in your thoughts if you've a moment to comment!  Many thanks...

2 hours ago, kitpw said:

If I've understood your illustration correctly, you have the pull rod connected to a crank on the lever arm.

I think that was a mistake and I've altered my drawing   I hope the new version is clearer,

1 hour ago, Mikkel said:

you simply scrape the comb mutliple times along the same lines?

Thanks Mikkel.  This video explains what old fashioned carpenters/joiners call a "scratch stock".  Usually made in house, they were used for cutting simple mouldings in wood. 

https://www.finewoodworking.com/2008/07/31/how-to-make-a-scratch-stock  There are one or two things to note about the cabinet scraper version I made. 1)  there are two sets of teeth on the one illustrated, only one set is necessary (I should have pointed that out in the original post). 2) the teeth are angled so that as they cut into the wood, they also move sideways slightly to form the characteristic angled louvre rather than just slats - if you see what I mean.... and 3) I start with a small toolmaker's clamp on the scraper so that it's held against the edge of the wood, hopefully to a straight line - a similar "fence" is built into the scratch stocks illustrated in the video.  Once the scraper has cut into the wood a bit, I take off the clamp and the scraper follows the lines it's already cut.:  it's one of those things that you really have to try for yourself, you'll quickly discover the ins and outs of it.  The wood I use is jellutong (I think it's also known as bass wood, particularly in US).  It's favoured by pattern makers, has a close, straight grain and is very workable.

Left: the scraper (used for No 88's louvres) with a toolmaker's clamp attached.  Middle: the scraper beginning to form the louvres (in a bit of mdf to illustrate how it works - not suitable for finished work!) and Right: another corner of the same scraper with a more traditional moulding shape in it -used for building cornice in 7mm scale.

2 hours ago, MikeOxon said:

I hope the new version is clearer,

...it is! And thanks for clarifying - I think I understand what's going on now and I can begin to work out the dimensions of the various parts, just as you did for the very nice broad gauge mail coach.  I meant to say earlier that I thoroughly agree about card stock in the Silhouette - I did manage to get it to cut plastikard quite well but, as you say, only thin stuff.  I seem to be using card (Bristol board) more and more, liberally coated with shellac.  Again, many thanks for your comment and research on the brake question, all very helpful.

Good day Kit,

You wrote "I illustrated the cut out and assembled sides some while ago (2 years+)", well I have gone through the blog end to end and I have not found the words and music about creating the sides.  Please offer a link to the relevant text/photos.

regards, Graham

37 minutes ago, Western Star said:

creating the sides

Hi Graham ...oh dear!  When the images were lost on RMweb a few months ago, I eventually attempted to reload the missing pictures from my files here....but clearly not that: my apologies.  I don't think I wrote much about it but I did have photos of the unpainted sides (only) which I posted again above.  There isn't a lot to say about them.  The artwork for the Silhouette cutter was created as DXF files in layers - the outer layer (1) being the panelling: the next layer (2) the main side which was scored on the Silhouette to represent the planking and with complete cuts for the openings for the side and drop lights of the grooms' compartment together with the louvres to the horses' compartment.  The next layer (3) had oversized cut outs to accomodate the glazing and louvres and the last layer (4) is the "interior" such as it is. I discount the panelling layer as a full layer since it contributes little to overall stability of the assembly. The material is all Bristol board coated both sides with shellac prior to cutting on the machine (I didnt take pictures step by step).  The layers were laminated using regular pva "white" glue, brushed on, and the layers set up on the turn-under former (pictured below) which is no more than a board in the shape of a carriage side with a straightedge at the base so it's pretty similar to the method for forming the roof except that simple weights (my grandfather's "gravity clamps") do the job.  The left hand picture is the whole former - long enough for a 60' coach in 7mm (some hope!) and the right hand picture is the end elevation of the former showing its shape.  Once again, apologies for the wild goose chase - I've been on a few myself, only to find those annoying "placeholders" and no picture.  Best regards - Kit