COMMON COMPOSITE PROBLEMS
Drilling in composite materials is a unique challenge. There are a wide variety of regularly machined composites, each requiring different considerations and approaches.Overcome common composite holemaking problems by identifying and selecting the right composite drill for your job.
Delamination occurs when high drilling forces cause laminated layers to separate, yielding less structurally-sound parts. The more blunt a drill point is, the more force it will take to move through a part, increasing the chance of delamination.
The separation of layers may be difficult to identify through visible scrutiny. Closely inspecting and testing the hole quality is ideal when looking for delaminatio
Defining Uncut Fibers
Uncut fibers are largely caused by dull tooling. If a drill' s cutting edge is not sharp enough, fibers will remain uncut, frayed, or splintered, potentially ruining the part.
Identifying Uncut Fibers
Uncut fibers should be easily noticed: look for splintered or frayed fibers around the edges of your hole.
Rather than leaving uncut fibers hanging on to a workpiece, dull tools can also grab fibers and tear them out of the material altogether. This can leave voids in your material and cause damage to even greater areas of the workpiece.
Tear-out can be more difficult to spot than uncut fibers. However, it is often seen as an area of material completely removed around the edge of a hole.
CHOOSE YOUR COMPOSITE DRILL
Double Angle Composite Drills
The Double Angle Composite Drills help combat delamination and push-out in layered composite materials with specialized point geometry. The primary 130° point angle allows the drill to efficiently engage laminated composites without lifting the top layer of material. The shallower secondary 60° point angle reduces the amount of force required to move the drill through the material, further reducing the probability of delamination. The higher shear angle also aids in reducing push-out at the back of the workpiece by more gradually breaking through the part.
Brad Point Composite Drills
The Brad Point Composite Drills are designed specifically for superior performance in fibrous composite materials. The trident-like brad point ensures that holes in fiber filled and reinforced materials come out clear and free of fraying. The outer points accurately score the outer diameter of drilled holes, eliminating uncut fibers, tear-out, and splintering.