The wax needs to be hot enough to boil the sap from the first two mm or so. I find brushing it on will leave it white and not sticking to the wood, so I use a hot air paint stripper to melt it in, just play the air stream on the wax until it looks 'wet'
I use a redundant chip fryer to melt my wax - no flame there, we are eating healthily now!
On the other hand edbanger has the right idea, use pva or any spare paint.
Ron