Re: PAINTS AND PRIMERS 4 ALUM. BOAT???
Any paint shop will have self etching primer, since it's covered by the final coat, I have never worried about using a particular marine grade paint. I buy mine from a local body shop supply, it comes in quart or larger cans with a tube or bottle of clear additive that you mix in prior to painting. I then lightly sand and coat with a good zinc chromate primer/sealer then the final coat or which ever marine paint you choose.
The self etching primer is also used on fiberglass and plastic parts, so I buy it in larger quanities, but it's not cheap. The last I checked it ran about $37 per qt. I also use it when repainting lower units and outboards, if you don't then most likely the paint will peel or flake off. I have had some luck with a few rattle can paints on aluminum, but I never tried painting anything large. I did the lower unit on my one boat with Mercury's OEM rattle can Phantom Black and it's lasted the last two years just fine. I have an old jon boat out back that someone painted with plain old paint, it looks like a lizard shedding it's skin, and it's just sitting turned over out back not being used.
As far as rolling the boat over, it depends on the hull design, I have seen a few that I wouln't try it with, but most are fine so long as they are complete and you make some attempt at supporting them across the top when they are on their side.
When I found my Duracraft, it was sitting turned over and on a rusted out trailer, it took four of us to flip it. Knowing that the floor was bad and that the side rod boxes had come unriveted, we chose to flip it over end wise on the transom. I slid it back off the trailer, stood it up on the transom and walked it down carefully back onto the trailer which a buddy has maneuvered around the other side. It took a few poles and three of us to walk it down but it worked with no damage.
It was a case of take it now or not at all, so we did what we had to to get it loaded and away. The hull and transom was sound, it was just that the guy that had it had already begun tearing it apart to replace the floor. If we would have rolled it sideways, the unsupported sides would have flattened at the very least.
The hull on mine gains most of it's side strength from the rod boxes and the secondary supports. The rub rail caps it all off and adds some rigidity as well.
