Hi Gill. I have made quite a few name signs for stables. I use Wilkinson's own brand of Danish oil. What I like about this is that it is thin so gets into all the little nooks and crannies. It also dries quite quickly and during the couse of a day four coats can be applied, which is more than adequate. Another solution is to use Sadolin, the advantage with this is that it is micropourous so wont crack or peel with the changing weather conditions and temperatures during the various seasons. I am not sure if you can get it in clear though, if you can then two coats will suffice after applying a sealer.