Adding a rib to an aluminum boat

[68camaro 1]

My older lund 16' boat has a leaky rivet. I was going to replace the rivet but the guy at Norm's said I should add a rib. Has anyone ever done this? I'm not sure this is necessary but if it's not too difficult I would tackle the job. Any info would be very helpful, Thanks.

[naden 131]

Replacing the rivet is pretty easy but not sure why you would need the rib. Most ribs that I can think of could not be made with normal tooling and would have to be bought. Only reason I could think of to add a rib would be if there is a lack of support in the area and the skin is oil canning in that area and causing the rivets to loosen up. If the rivet hasnt been tightened up before and isnt work hardened yet you could probably just buck the rivet some more and stop or slow the leak at the rivet. If the rivet has been loose for a while the hole is probably enlarged and you should replace with an oversize rivet. It wouldnt be difficult to add a rib, it would just involve drilling and deburring appropriate sized holes and then bucking the rivets. Just make sure to leave enough edge distance when drilling your holes. Usually the hole should be 2 times the diameter of the rivet from the edge of the aluminum. When the unbucked rivet is put into the hole in the aluminum the tail of the rivet should protrude by one and a half times the diameter of the rivet. Make sure to match the rivet material to the material of your boat, which is probably 5052. Holes for rivets are usually drilled with wire size drill bits. For a 1/8 rivet use a #30 drill, for 5\32 use a #20, 3\16 use a #10 drill. If reusing existing rivet holes drill the old rivet out with a slightly undersized bit, #31, #21, or #11 so that you dont enlarge the holes.

Hope that helps!!

[68camaro 1]

Wow, thanks for the details Naden! To answer some of your questions, the rivet has been tightened up before and stayed tight for over a year. The area around the rivet is oil canning and thats why the tech at Norm's suggested to add a rib. It sounds like you've done this before. I'll have to ask Norm's if they can make or order a rib for my boat. Thanks for the help Naden.

[naden 131]

No problem