Yeah I thought that too. I work as a maintenance mechanic in a welding fab shop with tons of welders and I see this a lot and usually it's a loose connection or something. But ive learned that the problem is usually where the heat is. For some reason there is allot of resistance there creating the heat. I may need a bigger fuse though I would've thought if it was to small it would've just popped. I'm thinking it's just inferior metal in the fuse block. It's always gotten hot it's just never been this bad but I've never pushed so hard either