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:

http://thedowerhouse.com/pics/bench.jpg

The photo shows one end of the seat.

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.

--
Mike Barnes

Probably dew.

cheers,
Pete.

Mike Barnes wrote:
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:

http://thedowerhouse.com/pics/bench.jpg

The photo shows one end of the seat.

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.


The colour you've got on the left hand plank is what I'd expect from an
oil finish on a sanded board. The right side looks like there's a
previous finish that the sanding hasn't completely removed.

In uk.d-i-y, stuart noble wrote:
Mike Barnes wrote:
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:
http://thedowerhouse.com/pics/bench.jpg
The photo shows one end of the seat.
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.


The colour you've got on the left hand plank is what I'd expect from an
oil finish on a sanded board. The right side looks like there's a
previous finish that the sanding hasn't completely removed.

I can understand why you'd think that, but there are some places (on the
back) where some traces of the previous finish (also Danish oil)
remained, and they've now blended in nicely. The current variation in
finish wasn't apparent after any of the first four new coats went on.

I'm going with the "dew" theory.

--
Mike Barnes