Having had a very successful trip to the 'Oak Fair' in Dorset this weekend, I noticed three makers producing oak rustic furniture, who had left the waney edged sapwood on the edges, just like Davetb's bench in another thread. To my surprise when asking what measures they'd taken to weather-proof it, 2 of these sellers had no idea that the sapwood would rot without treatment, they seemed to think because it was oak, it would be fine. Alas, neh- happy days for the woodworm and fungi friends.
One maker was producing a range of deciduous softwood items with no exterior treatment and hadn't given it any thought. He was a bit proturbed when I told him his lovingly made items would decay as they currently stood. 'Spose we'd better look into that', he mooted.
I've subsequently done some googling for a solution as I very much like waney edged stuff and would like to make some myself, but not have it fall apart. I think for anyone wanting to protect benches, seats, tables, arches, or whatever, made from perishable wood left outside, this is a pretty fundamentally useful point worth discussing.
Possible solutions are something like this stuff;
http://www.wood-finishes-direct.com/product/wood-preservative
It seems an exterior preservative every 5 years plus oiling with something like 'decking oil' every year or two will (if as claimed) provide good protection and extend the life of the item into many years hopefully (?).
Anyone tried other treatments with success or can confirm the effectiveness of the above type of gunk?
