Drilling and Boring Tools
General Tips for Drilling
- Back the workpiece with scrapwood to minimize splintering when the bit breaks through. This doesn't always guarantee a splinter-free hole when you're using twist drills, however.
- Feed the bit steadily into the work. Don't force the bit, trying to make it cut faster than it's able to. On the other hand, don't feed it with such light pressure that the bit rubs without cutting. Either situation can overheat the bit, dulling it and possibly burning your project part.
- Always secure the workpiece solidly. When possible, use a drill press, and clamp the piece being drilled to the table. When using a portable drill, clamp the workpiece, and use both hands to hold the drill. Be sure to use an auxiliary side handle when using a large bit in the portable drill.
- Before you start the drill, chuck the bit tightly. Give the chuck key a twist in each of the three holes around the chuck body.
- Where eye protection whenever you're drilling.
- Clear chips from the hole as you drill. If you're drilling metal, don't sweep the chips away with your hand -- they can be razor sharp. Instead, blow them away or use a brush.
- Remember that the bit will be hot, possibly very hot, after drilling. Don't grab hold of it as soon as you pull it from the hole.
- Use only sharp bits. You can sharpen twist drills yourself -- although the smaller ones can be difficult to sharpen well. Spade bits sharpen easily.
- When you have a choice, buy bits made of high-speed steel (HSS). They'll hold an edge longer, even if you run them hot. Carbide-tipped tools last a long time, too. (But don't think that carbide-tipped twist drills for masonry drilling will help you in woodworking. They won't.)
To receive a comprehensive drill-press speed chart for use in your shop, send $1 for postage and handling to WOODŽ magazine Speed Chart, 1912 Grand Ave., Des Moines, IA 50309-3379.
Add your comment
Please confirm your comment by answering the question below and clicking "Submit Comment."