Since I duck hunt in this boat, I'm posting in this forum.

I have a riveted boat with a slightly rounded hull where these ribs are attached. The ribs have cracked in a few places and need replacing. I could weld this up, but the metal is super thin and and I don't see that being a strong solution.

Possible to remove, replace with some wide (4"?) 1/8" flat bar and bolt it up with some 5200? Any reason why I should have new ribs fabricated vs just bend some bar? Because of the rounded hull I think having custom ribs fabricated will be more trouble than it's worth, and I'd like to get another season or two out of it.



These cracks are in the middle, but the ribs are similarly cracked on the ends:

I"d wear a life jacket and tie a rope to my gun ------- when it falls apart it will be an adventure you can talk about for years to come.

The bottom of our jon boat at home had been held together with kitchen screen and JB Weld for the last 15 years. 1 strip up a seam, and 1 hole about 4" round from a shotgun falling over and discharging in the boat.
(That guys hasn't been invited back)

I bet you can form an aluminum flat bar over it and braze it on. A mig welder will handle that thin stuff as well. Just do spot welds until it is filled in. I would drill out the rivets and add another layer after it is mig welded.

Why even use all that aluminum? I could be using flex tape for this whole thing.




That would be easy enough. I can weld it up and see if it doesn't break again. I'm really wondering if the formed ribs hole any advantage over thick flat bar.

I expect the do since the formed ribs resist stress from many angles. I'm wondering how hard it would be to form another thin sheet of aluminum over the existing one and rivet it down.

You're right. I'll do just this, or maybe just some angle on the flat parts of the rib. Should hold well enough and I don't need to worry about heat tempering the metal (and more cracks) down the line.

That flex seal stuff actually works really good. I'd fix it and coat it in that and call it a day. Without any worries

I wouldn't waste my time welding it. Aluminum is really porous so far as a metals are concerned. It would be really hard to get it clean enough to weld and when you do, you're dealing with a really thin piece of aluminum anyway. Find a way to bolt something on, use some kind of whatever "gorilla snot" sealant and roll with it until the wheels come off. The cheapest fix will be a ten dollar gallon of roof tar cement. I use it to fix decoys after I go hunting with Dave Speer and GR Elliot.

gluvit
http://marinetex.com/products/marine-tex-products/gluvit/

I would take it to the scrap yard and know that 6 months down the road it would be a natty light can.

My old Tracker Grizzly did that. 2-3 breaks on each rib. McGill Propeller welded it up and I never had another issue.