In a nutshell, I cut a piece of brass rod that fits the length of the mold I want to core color. Semis pic shows what it should look like with the pins in place. You just have to make sure your pin diameter doesn't close off the gate too much. Gate = the hole that leads directly to the bait cavity. Once your pins are cut , I rub a little worm oil on them, set them in the mold, then shoot the outer color. Once the baits cool off enough to handle I remove the baits then remove the pins. The worm oil helps ease pulling the pins out of the baits. Now you have baits with a core hole all or most of the way through your bait. I then make sure the core hole doesn't have any obstructions on the ends, I place the cored baits back in the mold then shoot my core color. There is a slight learning curve/trial and error to shooting baits like this but it's not too difficult. You will have the process down in no time with a little practice. The main thing ( I think ) is to not use to large a diameter core pin and shoot your plastic a little hotter than you normally would.
I use brass rod but you could use any metal rod. I like using brass rods and buy them at the local True Value hardware store.
Some molds are super easy to E core while others are not worth the hassle. I've never shot any Senkos before but just by looking at the pics it should be a super easy one to E core. What bait/baits are you wanting to E core ?
Oh , and with semis baits above. I think I would try a slightly thinner diameter pin and/or try filing the end of the pin to a point on the gate end of the mold.
I have no clue what your experience level is but I suggest you get a little experience shooting one color baits first. Once you have those down and understand the process then try doing some E core baits.
Welcome to the board and don't be afraid to ask questions if/when you run into any problems.
