A new product added to the Railway Laser Lines this month is the pack of 15x OO Gauge 3 Panel Concrete sections along with 16 concrete posts that will give you a length of fencing around 475mm.
The panels have 3 engraved lines horizontally on both sides to respresent singular concrete panels and 5 of these make up a block.
Simply use a sharp modelling knife/zippy blade or equivalent to cut the panels from the template. Do the same for the concrete posts and then slide the panels inside the posts and glue along the vertical lines using a very small amount of PVA glue using the dabbing method. Immediately wipe away any excess glue with a small brush. Hold each post in place with you finger/thumb to bond, then release and do the remaining ones. When it comes to joing the two panels together the centre post should be glued half one one side and half on the other to give that perfect join. Add some additional glue to the sides of the ends of each concrete panel. Allow to fully dry. Paint and weather accordingly if desired.
NB: Image shows 3 panel version