A
bowmaker recently taught me how to rehair bows. He recommended that I prepare the bow for the customer with powdered rosin to give the customer's rosin something to stick to. I use an old toothbrush to lightly brush some rosin into the fresh hair. That's how I do it.
Less work for the customer results in happier customers, and that's what it's all about. If the customer doesn't want me to do it, that's fine with me.
Michael