I'm wondering if a different penetrating oil might work better. I know it is a pain in the pocket book to have a variety of penetrating oils. Many of the comparisons of penetrating oils have a variety of outcomes. I picked up some Kroil at a yard sale and my brother said that was really good penetrating oil. I've used it some, but don't remember what on. We had a stuck screw on a White that we put Tri-Flo on one night and the next morning it came out, but I don't think it was rusted.
I'm wondering if tapping the top and/or the bottom of the plate some to give the penetrating some place to go into. It seems like after reapplying penetrating oil and letting it set, reapply and then heat and tap. One of the videos I watched comparing various oils applied 3 times and let it set for 24 hours.
I hope you are using a piece of wood against the plate as you are. trying to tap it out.
Janey - Neat people never make the exciting discoveries I do.
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