Believe it or not, this contraption works (at least in a MD summer).
 
You will need:
 
An old picnic cooler w/o the lid
A piece of Plexiglass big enough to cover the cooler
A black plastic trash bag
An embroidery hoop large enough to be held up by friction in the cooler
Nylon bridal veil cloth (enough to put in the embroidery hoop)
Two bricks
A clean aluminum pan that once held a frozen dinner
 
 
Line the old picnic cooler with the trash bag, and then put in the aluminum
pan.  Put your bridal veil cloth in the embroidery hoop, then wedge the hoop
and cloth in the cooler.   Put your cappings on the cloth, then put the whole
thing out in the sun before noon.  Put on the Plexiglass, and weight it in
place with the bricks.   The melted wax will solidify by dusk; remove it
then.
 
This melter will do about 1 1/2 pounds of cappings a day.
 
W. G. Miller
Gaithersburg, MD