I've treated an old garden bench with Danish oil and the first four coats went on fine, with gradually improving colour and sheen. A couple of days ago in the evening I put on the fifth (and final, I thought) coat, but when I came to look at it in the morning things had gone very wrong.
Most of the horizontal surfaces had gone back to a completely dry, matt finish. I've tried to photograph it but I didn't find it very easy - here's the best I can do:
The expected finish is seen on the vertical centre plank, the areas around the bolts, and the top and right (in the photo) edges of the horizontal outer planks. Other areas (not shown in the picture) that look the same are the undersides of the seat planks and all of the backrest planks. In real life they look wet (but they're not).
The unexpected finish is seen on the rest of the wood, which has gone right back to a completely pale, dry, finish almost as if it had never had any oil on it at all.
Obviously I'm going to recoat it but does anyone know what might have caused this? AFAIK it didn't rain and there wasn't a frost. The bench would have received full morning sun before I saw it. I've left it a couple of days to see if anything changes, but it hasn't.