Actually a rubber mallet is pretty effective. So is a "spreader", which is like a clamp, but works in reverse. The two thoughts are that a quick smack can just pop the parts apart. A slow steady outward pressure can pull them apart. In both cases, the possibility exists that there may be tearout from the disassembly.
If the joint is glued, try a heat gun. That should loosen the bond.
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If the joint is glued, try a heat gun. That should loosen the bond.


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