We present an improved version of an earlier Larson-type model of amph
iphiles. Detailed descriptions of the algorithms are given and some si
tuations where care must be taken are pointed out. We use the model to
calculate the condensation transition temperature of amphiphiles in a
ternary mixture. The concentration percolation threshold and percolat
ion critical exponent of amphiphile clusters at the oil-water interfac
e are also calculated.