Just got a "new" old boat. I think it's a 16' Lone Star, but nothing really matches up.

[sonny1]

I plan on running mine with a 8 HP Mercury. Everyone on here has mentioned to stay away from the single cylinder 4 strokes. Eight Horse power should be plenty for getting around the lake. The plate on my 14 footer says Ten HP max.

 

[WolframM]

Finding some more information. Got the holes patched up too.

Here's the hole in the bottom of the boat, before I started scraping off the JB weld that was there.

This was easy enough to fix once I got the boat up on the sawhorses and started cleaning off the old paint.

You can kinda see the big dent right there on the riveted seam, but

Took a lot more cleaning to get the panel ready to weld, but it cleaned up fine.

Next up is the float test. Gonna go float it on a local pond to make sure it doesn't leak, and if it does, we'll mark them up and I'll swell rivets or replace them if I need to.

 

[sonny1]

Welded up fair. After seeing your results may go ahead and weld crack on mine.

 

[WolframM]

Stainless wire brush, make sure your patch is at least 3/8" longer than the crack you're patching, and wipe with acetone before welding. Same rules for using "alumi-weld" too, you could braze the patch on with a (admittedly large) propane torch, and it'd work just as good as long as your patch fits the curves and distortions in the panel well.

Never use a flap disk or sandpaper, they are most likely aluminum oxide grit and are just going to add to the oxide layer you're removing, and never a carbon steel brush, as it'll embed iron and iron oxides into the aluminum and both will cause trouble, during the weld and after welding.

 

[Steph Boeker]

Finding some more information. Got the holes patched up too.

Here's the hole in the bottom of the boat, before I started scraping off the JB weld that was there.

This was easy enough to fix once I got the boat up on the sawhorses and started cleaning off the old paint.

You can kinda see the big dent right there on the riveted seam, but

Took a lot more cleaning to get the panel ready to weld, but it cleaned up fine.

Next up is the float test. Gonna go float it on a local pond to make sure it doesn't leak, and if it does, we'll mark them up and I'll swell rivets or replace them if I need to.

BTW, can you grind that flat or smooth it out in any way or will it weaken the fix ? I don't mean to offend , but think it looks like a very talented nice weld job. But , I'm not really knowledgeable about these things and want to know the details ??

 

[WolframM]

Nope. The skin of the boat is too thin to grind that down, that's another layer welded over the crack. You could grind out the crack, drill both ends, and weld the (very thin) aluminum hull, but you'd be asking for problems.

You could smooth it out with a sanding block and some elbow grease but there isn't any need to, it's not like it's gonna go more than 10MPH at any point in it's life.

 

[sonny1]

So Mr WolframM how long have you been welding?

 

[WolframM]

Nearly 18 years now. Before I became a high school teacher I did aluminum casting repair for about half my business in the machine shop. Fixed a few boat hulls, trying to treat them like regular sheetmetal always resulted in a comeback. Put a patch over the crack instead, and the repair lasts.

 

[sonny1]

When your dealing with old contaminated stressed out aluminum a patch is a wise choice. I have a small crack on my boat and it had been repaired with 650K epoxy and fiber tape. The patch was on the boat when my wife's brother bought the boat. So I know it was at least 5 years old and it did not leak. Kind of sitting on the fence on making repair. Weld or go back with same patch? By trade a Tig Welder. Everything from military planes to military ships. Over 20 years experience. Knowing how old aluminum sometimes does not work out as planned I am not sure which route to take. After reading your post kind of thinking about welding the crack.

 

[Steph Boeker]

Nope. The skin of the boat is too thin to grind that down, that's another layer welded over the crack. You could grind out the crack, drill both ends, and weld the (very thin) aluminum hull, but you'd be asking for problems.

You could smooth it out with a sanding block and some elbow grease but there isn't any need to, it's not like it's gonna go more than 10MPH at any point in it's life.

BTW, I'm no welder but have been studying lately to learn and even have my welder , a line on a bottle of Argon and plenty of alum scrap for practice w/good material for framing my floor , boxes and such. I'll be spool gunning or mig welding it but your work looks so nice I wonder :
Is that tig welding you've done ??

 

[WolframM]

Yes, it was tig welded.