30 to 50 amp. Problem adapter/converter melting and failing

driller wrote:
The receptacle is fine it's only at the adapter on the 30 amp plug side! All the signs point to pulling to much power.

Often it is the weak crimp connection on a moulded adapter.

You could try this premium replacement plug from progressive industries.

http://www.progressiveindustries.net/tt-30p-connector

Of course best would be to upgrade service. If you can pull just one #10 wire and pop in a double 30a breaker you could double your power and use a 14-30 outlet.