Back again. I tried to get the boat booked in for some repairs, but I guess its a busy time of the year and I was wanting to take it on holiday in 3 weeks time. So I took the plunge and brought some supplies to make a few repairs.
Ive had the boat on my stand and while scurrying around earlier in the week realised that I could see daylight through the floor in a few places. probably about 20 tiny pinholes. The pinholes were in lines, which I think align with the board joints. I reckon the previous owner using the boat without the stretchers might have contributed to this. Most of the holes had been sealed with some gummy stuff, but it was quite easy to rub it off, so this was an added issue, in addition to the stuff I'd already found when I did the leak test.
My plan had been to remove the loose patches and re patch them.
The ones on the transom pulled off pretty easy
I'm not sure what they were covering.
From what I have read and been told, patching near a seam is not very sucsesfull, because the water can just track along the seam. I decided to try and increase my chanced of sucsess by putting a big patch, with healthy overlaps across the whole transom. My theory being that at least the large overlaps would be sitting nice and flat on the tubes and floor and be well sealed.
It started off like this:
Then I cut a bit of a pattern (forgot to take photo) and it ended up looking like this:
It was very stresfull trying to glue something with 2 part contact adhesive that was so large and went over so many uneven surface, but I think it looks fairly neat.
Next I removed another loose patch. There was a little tear under this:
I made a patch from the offcuts of the transom repair. Peeled off the loose glue and then removed the rest with the MEK solvent.
I decided to patch the little pinholes from inside. Firstly there was a lot of manky sealer on the outside. Secondly, it made it easy to see the light coming through. I just went patch crazy, making my own from more offcuts. The downside of this method is that I couldnt apply as much pressure upside down, but they seem to have taken well (once the glue is going off it sticks on instantly), so we will see what happens...
While scramballing around underneath the boat I did notice a bit of degregation at the base of the transom, which I couldnt see when the boat was right way up. I got a cloth with some solvent and was able to work my finger in cleaning the joint out as best I could, until I got back to what I felt was sound joint. In both cases it was about an inch. I then glued it up (or to be more precise glue - dry - glue - dry - stick) and made some props to hold the seam together tight.
Props in place:
Ive got to leave it all to dry now. I may try another leak test tomorrow to see if I have stopped any of them!