Just wondering how to get the darkest black dye job from using walnut hulls ?.

Don’t scrimp on the amount of hulls you use and be careful to start out with enough water so that repeated heatings will continually reduce your dye solution making for a darker & stronger dye.

Pretty simple, just put a big pile of walnuts in a barrel, bring it to a boil add your traps, wait 5-10 min and remove the traps from the dye. If your traps have a nice light coating of rust they dye very dark. If they are shiny they would dye as dark.