I have this Radisson 12’ birch bark painted double pointed canoe. On the bottom of the canoe it has 3 keels, the main center and then 2 side keels for stability. Well let me say this about the side keels they suck! Well I got tired of hanging up on rocks every time on the sides keels. I turned the canoe over and decided to remove them, at first I had to see how they were attached. They had screws in them and then just the bow & stern of the keel had putty substance that made it waterproof. I got my grinder out and away I went. I had to get a thin plate grinder, now the biggest thing is patching the area after removing. I have used all types of patching items, now this is my choice in the BEST patching. It’s called LABMETAL by ALVIN Products. It can be put on by putty knife, or any type of blade, also can be thinned out to be sprayed on and roller brushed and paint brushed. After application is put on, let dry about hour to 2 hours can be applied again for 2nd coat. Then can be grind down and sanded real smooth. Then painting can be done after that it is completed and start paddling on the water once again!.
J B Weld - available in any good auto parts store. Probably not economical enough in the quantities you may need for that kind of repair. It is the toughest stuff for metal repair outside of actual welding. Just an FYI.
You know to use a grinding wheel designed for the metal you are grinding? The problem is that some of the steel designed grinding wheels load up, heat up and fracture.