Hi all, I recently purchased a “Metal Blackening kit” from EW and put it to work yesterday. Some nuts and bolts came out OK, but I have some grade 8 bolts and hardened nuts that didn’t respond to the blackening at all! Do I need to bead blast before or is it a lost cause? By the way, it’s going to be about 74 degrees out here in sunny California hope all have a Happy Thanksgiving. Thanks for all the input.
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