Cooling-Channels

I’ve drilled a lot of mold cooling channels. Injection molds, blow molds, extrusion dies — they all need holes for water to flow through, and those holes need to be straight, smooth, and exactly where the print says. (It’s a different challenge from drilling long shafts — with molds, the angles and material hardness are what get you.) The standard approach is gun drilling, and for good reason. A gun drill can put a hole through a block of H13 that’s straight to within 0.1mm per meter and leave a surface finish that doesn’t need any cleanup. You can’t do that with a twist drill. ...

Cooling channels get most of the attention in mold deep hole drilling — I wrote about those here. But molds have other holes that need to be right, and some of them are harder than the cooling circuits. Ejector pin holes, guide pin bores, and insert pockets all have their own requirements. I’ve worked on all of them, and each type has tricks you learn by doing. Getting these holes wrong can ruin a mold that took weeks to design and thousands of dollars to machine. ...