Well, it seems that my varnish has a problem and unless I find a way to sort it out, I shall have to remove the varnish applied so far and start again.
As you can see from this photo, the varnish hasn't covered properly.
Here's a closer view and it looks just like water on a glass surface.
I think this is known as Crawling Varnish and although there are a number of reasons for this issue, the only one that I can see applying in this case it that the varnish is, in effect, too shiny. Too much of a glossy surface make the wet varnish act as though there was oil or grease on the surface to which it is being applied.
So, how to remove the shine?
Well, one of the things you can do when varnishing if you want a satin finish, is to polish the final coat with 000 grade steel wool. This removes the gloss and leaves you with a fine satin finish without removing much of the varnish.
I've never done this myself but it sounds like just the thing to solve this problem.
Tina uses this to polish up her armour. It is only 00 grade steel wool, but since I'm not worried about a super fine satin finish, this will do the trick.
So I set to and after 20 minutes or so I have apparently removed the gloss from the varnish. Unfortunately I now have fine steel wool dust all over the place and if I don't get it all out, I'll soon have very fine rust everywhere. Still, I bought a small vacuum cleaner for this very thing and used that to remove as much of the steel dust as I could see.
Here is the result taken about about the same place as the second photo from the top. Not much shine left here, so now to put on another coat of varnish and see how that comes out. I expect that the crawling varnish problem will be sorted but the uneven surface left as seen in the first two photos will probably mean that the varnish now has an uneven surface which I will need to lightly sand flat once the latest coat of varnish has dried. Hopefully a fair bit of the unevenness of the varnish will be smoothed out by the latest coat of varnish and I may just need to use the steel wool again between a few more coats of varnish to remove the uneven surface completely.
I shall see how this comes out tomorrow.
Time for a cup of tea.
[Edited 2020.09.20] I left the next coat of varnish for several days to harden properly.
As you can see from this photo (just) the varnish has lost the water on a waxy surface look but it is still lumpy, too lumpy for subsequent layers of varnish to flatten out, so I'll sand this all flat, or flatter and see how varnishing it after that works. I probably will not flatten the bits under the side decks, you can't really see those so the finish doesn't look too bad, but I will remove the gloss from all the varnish before putting on the next coat since it is obvious that the high gloss was the cause of the crawling varnish.
Having left the last coat for a number, it should sand fairly easily without clogging the sandpaper and the flatter I get it now, the easier it will be to sand off the gloss on subsequent coats.
Time for a cup of tea.