If the plate is soup plate shape suggest minimal pressure ie dont walk on it!!!!!!
Maurice, February 2011
Just an idea---
Depends upon how warped the plate is and how thick the brass is. If thin then
Place the plate on an even very flat surface cover it with a polythene sheet and then place a large sheet of wood over the plate add weight till flat.(even walk on the wood )
Or take it to a local sheet metal company who may be able to roll or beat it flat
Maurice, February 2011
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I can answer this question...
How to unwarp a brass plate that is 36" diameter which is used for a table ?