It is best if the wood is very dry before sealing with wood preservative.
This helps to ensure the ladder line wood dowels don’t become slight electrical conductors.
Bake the wood long enough to dry them. This takes a variable amount of time. What I found is the wood will generate smells for a while and eventually stop smelling when mostly dry.
I used a very low oven temperature of about 200-250 degrees F. You don’t want to burn the wood, but you want it hot enough to drive off the water content.