aluminum boat repair ?

[smokin-joe]

I went out on willard sunday but didn't get very far when i noticed i was taken on a bit of water[pirate]. I headed back in and went home to take my boat apart. I share a boat with my bro[angelic] i fish in the summer and he duck hunts in the fall and he must of hit something last fall cause i took the floor out and found two cracks one in the center seem about 5 inches long and one on the corner bout three inches long[pirate][pirate]. So my question is should i tig weld it or mig weld it my bro says if i mig weld it the heat will make it more brittle and i'm not set up for tig welding any thoughts or suggestions would be greatly appreciated. Thanks in advance Joe
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