I don't know if this is a good idea ..
Perhaps Dana and Jim can comment.

But what I have used for touch-up and remelting
wax in small areas, is a Weller adjustable
temperature solder station adjusted to a very low
temperature. It has a small chisel tip.

It seemed to work well for me. I can melt or puddle the
wax with no danger of burning anything because of
the low temperature setting.

--Big Nick

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