The figure I was taught was 5.5 to 6.5 lb of honey to make 1 lb of wax,
with the source quoted as Huber (the famous blind Swiss beekeeper-over
200 yrs ago) , confirmed by Simmins (1886)
Since honey is only about 80% sugar this would equal about 4.8 lb of
sugar and since nectar (in the UK anyway) is often only 30% sugar it
would require 18 lb of raw nectar for a lb of wax.
1 lb of wax will produce about 500 square inches of  foundation (note -
not drawn)
I seem to also remember a figure of 10,000 bees taking 3 days to produce
a pound of wax, at 1/2 million wax scales per pound.
However, the point is well made that young bees "want" to produce wax so
allowing some wax production is probably a good thing.
Alan Riach
Bathgate,Edinburgh