Composite Drill Selection Guide

Harvey Tool’s Miniature High Performance Drills for Composites are specifically designed with point geometry optimized for the unique properties of composite materials. Our Double Angle style is engineered to overcome common problems in layered composites and our Brad Point style is built to avoid the issues frequently experienced in fibrous composites.

Contact Engman-Taylor for more information on drilling, milling, and machining composites and plastics.

Identify your Problem
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 drill for your job.

Delamination & Push-Out
What It Is: 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.

What It Looks Like: The separation of layers may be difficult to identify through visible scrutiny. Closely inspecting and testing the hole quality is ideal when looking for delamination.

Ideal Drill Choice: Double Angle Composite Drills - Shop Now

Uncut Fibers
What It Is: 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.

What It Looks Like: Uncut fibers should be easily noticed: look for splintered or frayed fibers around the edges of your hole.

Ideal Drill Choice: Brad Point Composite Drills - Shop Now

Tear-Out
What It Is: 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.

What It Looks Like: 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.

Ideal Drill Choice: Brad Point Composite Drills - Shop Now

Choose Your Drill

Our new Composite Drills are engineered with point geometry optimized for fibrous and layered composite materials. Each design is specifically built to overcome common composite drilling challenges and achieve excellent results.

Double Angle

Avoid Delamination and Push-Out
Our 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

Avoid Uncut Fibers and Tear Out
Our 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.


Miniature High Performance Drills for Other Materials

Our Composite Drills are only our newest addition to our line of Miniature High Performance Drills. We also offer miniature drills specifically designed for Prehardened and Hardened Steels, Aluminum Alloys, and for Deep-Hole Drilling.
















Engman-Taylor is an authorized Harvey Tool distributor.  Since 1985, Harvey Tool Company has been providing specialty carbide end mills and cutting tools to the metalworking industry.

Information originally posted on Harvey Tool's website.  http://www.harveytool.com/cms/compositedrills_444.aspx

See also: Harvey Tool Plastic Cutter Selection Guide

Shop For End Mills for Plastics and Composites

Compression Cutter for Composite Materials

This week we took an in-depth look at Harvey Tool compression cutters.  This one was an easy choice; first off we have had a few requests lately for tools specifically designed for composites and secondly Harvey Tool provides some excellent technical articles on their website.  If you do any machining at all you are already familiar with Harvey tool but on the outside chance that you are unfamiliar contact Engman-Taylor - we would be delighted to ship or deliver a catalog you.

Composite Materials

First of all let's explain "composite" materials.  Composites are materials, and the machining of, are growing in popularity mostly because of the aerospace industry and in performance automobile manufacturing.  These materials though are also appearing in bicycles, bathtubs, guitars and other commonly produced products.


Composites are a group of materials made up of at least two unique constituents, that when combined produce mechanical and physical properties favorable for a wide array of applications. These materials usually contain a binding ingredient, known as a matrix, filled with particles or fibers called reinforcements. Composites have become increasingly popular in the Aerospace, Automotive, and Sporting Goods industries because they combine the strength of metal, light weight of plastic, and rigidity of ceramics. Many times a composite is used in cases where an extremely high strength to weight ratio is needed. A composite is also often layered with varying fiber and tape orientations, which help to increase strength in the material.

Composite materials are generally machined using standard metal cutting end mills. These unidirectional helix mills bring a few issues to the machining process such as lifting, fiber pullout, and de-lamination in layered composites.

Machining composites can be difficult because of two primary factors.  First of all composites are very abrasive, and can prematurely wear most cutting tools including carbide tools.  Secondly, composites tend to de-laminate during milling and drilling operations.  Sharp edges and space -age coating can increase tool-life but tool geometries can help here too.

Harvey Tool Compression Cutters 

To combat these machining challenges, the compression cutter has both an up and down-cut helix. The top half of the flute, closest to the shank, has right hand cutting teeth with a left hand spiral, forcing chips down. The bottom portion of the flute, closest to the end, has right hand cutting teeth and a right hand spiral, forcing the chips up. When cutting, the opposing flute directions generate counteracting up and down-cut forces. The opposing cutting forces stabilize the material removal, which causes a superb finish on both the bottom and top of the workpeice, limits fiber pullout, and stops de-lamination.

Choosing the Right Diamond

Another factor to consider when machining composites is the abrasiveness of the material. Glass and carbon fiber filled materials have the tendency to wear down the edges of carbide cutting tools. To account for the rough nature of composites, the compression cutter is offered coated with Amorphous Diamond, a PVD coating with DLC properties, and CVD Diamond, a diamond coating that is chemically grown onto the carbide. Each coating is better suited for different materials. The Amorphous Diamond is a thin layer of diamond that does not experience edge rounding from the thickness of the coating, making it suitable for materials that contain less than 30% of abrasive fill. Since these materials are more matrix than fill, they will create a chip when machined. When cutting materials with a higher concentration of fill, the CVD diamond coating is found to be very beneficial. The CVD coating is five times thicker, and has superior abrasion resistance to the Amorphous Diamond. At the micro-level, the cutting action is similar to that of a grinding operation, which makes the coating best suited for heavily filled composites that will produce a powder-like chip when machined.

Example of Milling Carbon Fiber: https://youtu.be/6-RjLwMOQBk

Sources:
http://www.harveytool.com/cms/TechnicalResources_266.aspx
https://en.wikipedia.org/wiki/Composite_material

Let us know some of the challenges you face in machining composites or show your composite material finished products.

Harvey Tool Double Angle Shank Cutters

With so many tools, from so many suppliers, we just can't share them all - but some are so useful we just have to tell you about them.

Take the Harvey Tool Double Angle Cutters:

Six Tools in One!

Double Angle Shank Cutters are often overlooked by many machine shops but these tools have some incredible applications that nearly every shop could use. Ideal for back chamfering, deburring, and milling a V-groove, Harvey Tool's Double Angle Shank Cutters solve a diversity of problems and improve efficiency.

Technical Resources

Speeds & Feeds

Downloadable and printer-friendly Speeds & Feeds are available to help you optimize running all your Harvey Tools. IMPORTANT NOTE: Each PDF is multiple pages long. Please scroll within the PDF to find the correct series number associated with your tool.

• Double Angle Shank Cutters - 30°-55° Included
• Double Angle Shank Cutters - 40°-50° Included
• Double Angle Shank Cutters - 60°-120° Included
• Double Angle Shank Cutters - 90° Included, Radiused

Simulation Files

Harvey Tool offers its master library of Simulation Files specifically scaled to the geometry of each tool to help you simulate running parameters and create tool paths.

Technical Articles

Use Angles Untangled to uncover the ins and outs of machining angles. This informative guide will help you select the exact tool for your application.

Have a cool use for double angle cutters that you want to share?  We would love to hear from you.

Contact us for question regarding Harvey Tool or any of the brands we represent.