How To Add Dimple Holes On A Bumper
The first step to adding dimpled holes, or lightening holes, is laying out your pattern. Masking tape works well to use as a canvas. Using the upper side of the metal as a guide, draw a line to help align the holes. Dimple dies work great as a template to find where you want the most inner and outer holes. Using a straight edge, mark the top of the holes.
Using a pattern maker or stencil the same diameter as your die trace out the remainder of the holes on the tape. Center punch where you need to drill and make pilot holes before using a step bit to finish it off. Depending on how you stack the dies on your panel will determine whether the holes flare up or down. Once in place, you want to apply just enough pressure to completely compress the dies together, not so much that it distorts or mars the metal.