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I need to make a thick base gasket cut from aluminum. 2, 2.5. Pictured is the shape i need, not the material. Does anyone have a way to do this. In the past I have tried a hole saw with the same diameter as the bore. The cut hole is sloppy. If I get it laser cut at companies around me its very expensive. $100+. Machine shops say its to small for there equipment (code for they dont want to do it.)

Thanks for the help!