I’m sorry it’s taken so long to reply. In the heat of battle I forgot to take pics during the work. However, I have attached a few of the finished product.
The client chose the Australian Jarrah from your website from Istanbul. Everybody is especially pleased with the railway sleepers themselves. So the free standing boards impressed many and those technically minded asked, "How the hell did I route that groove?"
We routed a 12mm central channel lengthways to a halfway depth (approx. 67.5 mm). We simply fixed a batten to the top of the sleeper and ran the router’s baseplate up against it. I knew my visits to the gym came in handy when I was able to control the movement of the router and, in several deepening passes (7-10mm) at a time and using 2 cutting bits (short then long), was able to cut a neat groove for the upstanding 12mm plyboard to the said depth. We pressure washed the railway sleepers too to make them interior friendly. All In all the freestanding blackboards were a resounding success to finish off the showroom and turned out better than expected by the client who ordered the work.
Thank you very, very much for you advice and prompt delivery.
RAILWAY SLEEPERS USED
Used Jarrah grade 1 railway sleepers
Many thanks for the detailed description of your work. As you say, there are always people to whom such precise information is invaluable. I'm glad that your gym exertions paid handsome dividends when it came to routing the Jarrah railway sleepers. They are pretty tough!