Re: aluminum boat hull restore/repair
Welcome to iboats John! I'm trying to grasp exactly what happened... is the hull bending under power? What size motor is on your boat?
8 of the 9 ribs were cracked in the center,the keel was hit by a log cutting a 0.5 inch slice out of the bottom of the keel.When I tried to plane off with a person sitting in the bow seat, the keel kinked and the ribs were already cracked so the boat tried to bend in half at the point were the keel had been
pinched.The bottom was pushing upward from just in front of the rear seat to
just behind the bow seat during plane .I decided to push the bottom of the hull back out slowly using a scissor jack from my truck, a chain running under the trailer and a 4x4 on the bottom(longways) and a 4x4 on top of the jack like a yoke/beam.The jack pushed up on the beam and don on the 4x4 at the same time.This worked surprisingly well.After that each rib was Mig welded and the
flanges hammered back into place.All rivets that were compromised were replaced and sealed with silicone upon bucking.I decided to add doublers to the ribs to help stiffen the ribs for I understand that welding aluminum can weaken the material.After that I installed stringers over top of the doublers and installed vertical tubing under the seats to keep the stringer down against the doublers.The stringers are 1.5 x 3/16 6061 aluminum 10 ft long.Then to keep the doublers in place I installed an outer set of angle on each side .The angle stringer also adds lateral strenght by helping to spread the load,and under the seat are the vetical tubes that intersect with another piece of 3/16 6061 riveted in place under the seat.I also had a doubler piece
welded over the damaged part of the keel which I will have to feather in using crc minute mend,sand and then paint.WHEW,WAS A lot of work but I am having a great time experimenting in the lab and sharing on i boat forum..Thanks for ques....John