Your options for a modern level crossing barrier with skirt are either Viessmann (two barriers with operating skirt; HO gauge (ebay approx. £156 including automation) or, Peco Wills SSM 318 four barriers with fixed skirt and accessories; 00 gauge (RRP £42.85 without automation. Over £100 with automation and DCC). Are there other manufacturer options? I don't know. How hard can it be to design one with an operating skirt myself? Answer: difficult.
First I had to find a dimensioned drawing. None found but, I did find a manufacturer's brochure here that has useful images from which I could scale the barrier for a two lane road width of 112 mm.
Designing it in CAD was straightforward for me but making the skirt move correctly is another matter.
The principle of operation for the model is for each upright stay to be bent 90 degrees at the ends and locating holes made in the boom and skirt base runner.
First, I made the upright stays from bent wire and it soon became apparent that it is critical for the stays to be uniform and all the holes to be perfectly in line. Otherwise, sticking will occur.
A eureka moment solved the stay uniformity problem when I found my office staples were the right length and thickness and I had loads of them. To hold them in place I used the sleeve stripped from copper wire making sure a small gap was left between the sleeve and boom/skirt base runner. Nevertheless sticking was evident, which I thought was due to friction between sleeve and boom/runner where the sleeve had moved towards the boom and runner. A more likely cause was the holes being very slightly out of line.
Final solution was to bend the staple ends at 90 degrees leaving a small gap between the bend and boom/runner and opening out the holes on the runner. This provides a sloppy fit of stays giving them free movement. As the boom rises the skirt folds up nicely - most of the time.
This project is for my Grandson's 'plank' layout. He wanted this style of barrier and wants it automated as well!
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