Brazing Aluminum - Boat

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I am a hobyist and thinking of fabricating a small sail boat. I would like to use Aluminum and also propane braze it. What I have seen on u-tube is that the durafix rods or whatever brand is strong if aplied correctly. My question would be about the zinc content and its durability to water exposure (fresh water). Boat would be in and out of water not constant. Dont want brazing welds to fall apart after a year from electrolosis.
Reply:NO no noSqWave 200Millermatic 190Airco 200 ACHypertherm PM45Boice-Crane Band SawVictor O/A
Reply:Aircraft rivets. Manual bucking.Bubble gumTooth pixDuct tapeBlack glueGBMF hammerScrew gun --bad battery (see above)
Reply:Bubble gumTooth pixDuct tapeBlack glueGBMF hammerScrew gun --bad battery (see above)
Reply:I can't imagine that working, even brazing a model boat.  You are in spool gun territory, everything else will have too much heat input and warpage.  However if you did, it would probably be the first brazed boat in history.  Have you ever tried those rods?  They always seem to work at the trade shows but never when you get home.  I still have some from an impulse trade show buy 25 years ago.
Reply:Originally Posted by blackbartI can't imagine that working, even brazing a model boat.  You are in spool gun territory, everything else will have too much heat input and warpage.  However if you did, it would probably be the first brazed boat in history.  Have you ever tried those rods?  They always seem to work at the trade shows but never when you get home.  I still have some from an impulse trade show buy 25 years ago.
Reply:Paul, the main issue with a small, soldered aluminum boat could be; the seams. You'd have to provide some form of overlap for the solder to adhere between the two pieces or hull panels of the boat.  Let's look for second at the chine where the bottom meets the topsides. One of these two pieces would have to have a 'flap' all along the seam so that it could be held to the surface of the other part of that seam.  This flap is not just a simple feat to design, to cut or to form and it surely would be an interesting feat to solder!If the boat is 14' long the flap might only be 3/4" to 1" wide and evenly spaced extending the shape of the seam at the bottom of the topsides? But how are you going to form a bend in the topsides along that seam to fold the topsides under the bottom so you can solder it?  Riveted hulls are done in this way but every single riveted boat is the result of more thousands of $ of machine tooling that we can describe unless Lund, Gregor, Monarch comes on here to post! The fixtures used to hold riveted boats while they're laid up and then riveted are highly precise and worth plenty more than 20 of the boats they're used to build.The thinner the aluminum the more sensitive it is to handling, skill, joints and heat.  Do you notice that there are virtually NO homemade boats of the size and scantlings/proportional thicknesses you're contemplating?  I mean where has anyone done what you're asking about?Last, let's just consider soldering a long thin seam of aluminum.  What holds this temporarily while its heated?  In welding we can tack weld, but if we "tack solder", the adjacent 3" of 0.060" or 0.040" is going to go 'nutz' and warp and have to be 'rollered' back to fair along the joints?I've built a couple hundred welded aluminum boats, and while I'm enthusiastic about all aluminum boats, I'm not sure you're realistically giving the various aspects of this idea and the materials an honest and real world evaluation?If soldering were effectively more efficient would the rivet boat manufacturers (notice I did not use the term builders) have stayed with rivets and sealing strips?  If soldering a boat was realistic- wouldn't there be at least one U-Tuber: wouldn't there?Good luck but, count me skeptical- interested but skeptical.Cheers,Kevin MorinKenai, AK