Bob, many thanks buddy. I had gone in Czech for a few days, and returned last night, so here is more progress....
I have found some unexpected issue that needs to be solved... I worked on base of two different drawings, one from my collection, which is more complex, but some small details missing, and another that sent me friend of mine scaned on paper, very large one, with many detailed drawings and cuts. I used it to create exactly the frame and some other parts, some brake parts I made on base of my drawing - in digital format in my PC just ideal to do PE design and prints for further work - so far so good - but never noticed that both drawings had different brake model. Large brake cylinder in one - Hildebrand brake I mentioned earlier, which I used - thin brake cylinder - probably the same manufacturer, but older make - in other. Well, I made more advanced large cylinder from one drawing, and the brake arms to operate whole system from another, where the cylinder was smaller - and the result is that 2 of 3 holes on one side are too close to the third one - all right for thin cylinder, but trouble for the other one - there is a crossing rod to be assembled in second holes - it has to pass the cylinder body, but that is too thick and it just wont
Not a problem to fix it, I could do either new older cylinder or change the PE parts for production. Easier way is to keep the advanced cylinder and change the PE parts. It is just about to move two holes a small bit inside, following the other drawing with large cylinder now... exactly what the test build is here for - to get everything right for the kit. For my test build I filled wrong hole with solder and made new one in correct distance.
I have added all the resin reinforcements underneath (thin pieces with holes are simply cut by the side edge, and then pushed in and securet with a drop of glue) and also other small details - another part of hand brake equipment - little cogwheel is placet exactly opposite to the sliding rod at the other side. Next picture shows final version of brake arms, which are now used to get together whole thing. There are some plastic rods involved, exact dimensions will be shown in assembly instructions, so just to mention that they have flattened ends which are to be placed between two PE arms. This is easy done with suitable pliers








Cheers
Libor