Update. I've made a little progress with a bit of a hiccup. I've finally installed the splash-well. I had to get over drilling through the new transom but also because of the way the whole thing went together had to figure out the steps I needed to take. Some bolts only went through the stern and transom while others went through the stern, transom and splash-well. I had to paint some areas first because my access would be lost once the splash-well was back in. Because several old bolt holes in the splash-well and the back of the boat had to align when I drilled new holes through the transom, I had to drill from the outsides to the center hoping they'd meet in the center. They did with only one near miss!
So as I said above I chickened out with the rivets and used 10-24 SS machine screws to put the splash-well back in. I used 3M 5200 under the heads and then caulked the joint inside between the splash-well and the interior of the boat. I also sealed the edge where the rear of the splash-well met the transom with 5200 and clamped it until it had set. I think I did all I could to prevent or at least delay the deterioration of the transom. I hope it'll be good for a generation but for sure it will outlive me.
On the original there were aluminum caps made to cover the top edge of the transom. They were pretty flimsy and had been nailed on so when I removed them they were pretty much ruined. In hindsight I wish I had made some kind of mahogany cap or had made the top half of the transom of mahogany but it was too late. So I was faced with having to become a tin-bender of sorts to make new ones. I'm not too happy with the outcome but it is what it is and I have to move on or I'll never get this thing done.
The old caps were pretty thin but heavier than standard aluminum flashing. I found a small sheet of .025 aluminum at Menard's that I cut into 3" wide strips (scored several times with a utility knife and snapped for a clean edge). I assumed the original caps had not been pre-made but formed in place over the transom. I wanted to make them without nails this time and so attempted to hold the aluminum strips in place with my small arsenal of clamps. It seemed like a good idea but with all the angles and shapes involved the clamps were all kittywampus and I had trouble keeping them in place. I tried a variety of combinations but when I started to pound the aluminum to shape it the clamps inevitably shook lose and I finally gave it up for a lost cause.
Here's one of the original caps.
And the attempted clamping
In the end I had to do what I had to do and used SS screws to hold the aluminum strips in place but at least they stayed put when I was shaping them. I don't like the look of them and the fact that they created even more holes in the transom but given the skills and tools at hand I got over it.
The shaping was fairly straight-forward once the strips were held in place. I used a variety of hammers and mallets I had around. A rubber mallet was most useful but I also had some jeweler's hammers that came in handy. The idea is to do the bending in a series of glancing blows with the mallet. You need to direct the force of the hammer away from the center to the edge. If you pound straight down or from the edge of the strip towards the center you might end up with a wrinkle or a badly fitting piece. Directing the blows from the center to the edge kind of drags the material away and down at the same time keeping the material tight as it bends down. I went the entire length of one side at a time working from each end to the curve at the center. You need to go slowly at the curve or the aluminum will crack. Working slowly, first one side then the other through a series of hammer blows will do the job.
After shaping each piece I removed them and sharpened up the bends on a bench vise by clamping the edge into the vise and a little mallet work from above. With most of the work use as broad faced tool as you can. A broad face will make for a smoother finish whereas a small faced tool will end up making a series of dents rather than one long smooth bend. Don't use a steel hammer. A wooden, rubber, plastic or leather mallet is best and I think the rubber is best as it gives a little and doesn't leave hammer marks.
Last thing yesterday was to clean up the castings with a wire wheel. I used a clear enamel designed for engines to coat the bare aluminum in hopes it might prevent the surfaces from becoming oxidized again. It's also supposed to be gas and solvent resistant. We'll see.
I'm really going to have to put this thing away for the season soon. I've neglected all my house and yard projects all summer in hopes of getting the boat finished by Fall. Well, the first day of Fall found me with a long way to go on the boat and a long list of things I should get done before the snow flies. I did hear a long-range forecast yesterday that suggested an el nino winter with warmer than normal temps. If that's true I may be able to make more progress on the boat and still fulfill my house/yard duties. Again, we'll see.
