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Join Date: Aug 2016
Location: Northern Florida (Almost Alabama)
Re: Best way to fix a bad bolt thread
Where are you getting these bolts from? Just like the SAE bolts, metric bolts also have different grades. Standard grade is 800-830 MPa, next toughest is 1040 MPa and the step up from that is 1220 MPa. You definitely do not want to put a lesser grade bolt there and try to torque it to something it is not, hardened bolts are a royal PITA to get out when they break.