I have always used turps for thinning, about 30% for first coat and 10% thereafter.

Thanks Jur about the China Oil, the cattledog says "containing pure tung oil".
I'll get my local guys to get some in and give it a whirl. I'm actually going to do my letterbox in Tung Oil just to see how it goes. My jarrah barbie is fairly exposed to the afternoon sun and sou-westerly weather and it has had Tung Oil (of what concoction??) on for four years. It is holding up well but gets a re-coat whenever I get guilty about it.

Cheers for the info.