Tool Review – Loren Sievila SHARPENING YOUR DRILL BITS A few months ago we discussed using a good cutting fluid when drill or taping operations on your project. Even if you always use cutting fluid, your drill bits will get dull and it will take more effort to drill a hole. You can always go out and buy new bits as the smaller one we often use aren't that expensive, usually less than $2.00 a piece. But if you have to get a new 1/4" x 12 " aircraft extension bit it will set you back $10.00 to $15.00 a piece. Investing in a drill bit sharpener will pay off in the long run. I have a Drill Doctor 750X which will sharpen up to a 3/4 " bit but there are smaller less expensive versions that will do the job. A Drill Doctor 350 will sharpen bits from 3/32" up to 1/2" and cost about $60.00. Of course there are other brands as well so just shop around. Keep in mind there are different ways to sharpen a bit so you should be familiar with the different kinds of points and make sure the sharpener you buy will do what you need it to. The standard point is the general purpose point that is used for softer materials like cold rolled steel, aluminum, and wood. The point can be 118 degrees or 135 degrees depending on what you are drilling. Soft metals like aluminum require 118 degrees and harder metals such as stainless steel and tool steel require 135 degrees. A split point bit is self centering and are generally used for tempered steels, hard alloys, or hard cast material. Titanium would require a slit point for example. All sharpeners are not capable of grinding a split point so be aware of that before purchasing. Keep your bits sharp and use cutting fluid and your drilling processes will be easier and you will have fewer broken bits and you probably won't need as many band aids!! 4 EAA1111.org .