It didn't matter what words I used I knew that part might come back to haunt me
Try and get a wrench size that allows for a piece of paper to be slid between the wrench and the blank to protect the blank, you want a wrench that is real close to the size of the male section so that the lip of the female section will sit on the flat part of the wrench, tap the wrench close to the blank making sure it's squared off 90* not at an angle so it is making the maximun amount of contact.
You can place the whole rod down on a blanket or a carpeted floor and just weight the bottom half to resist moving while you use a quick sharp tap on wrench side parellel to the female lip. This allows the rod to move yet hits the female portion with full impact gun type force which should pop it loose. It spooked the hell out of me doing it to an arra I built, but I took my time and got it to release. If the towel wasn't on the top half it would have went flying so remember the towel if you have to get this extreme.
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