Woodworker's Journal 2009-33-2, страница 16

Questions & Answers

Making Wood Hold Fast

THIS ISSUE'S EXPERTS

Rob Johnstone is editor in chief 0/Woodworker's Journal.

Bruce Kieffer is a professional woodworker from Minneapolis and frequent contributor to Woodworker's Journal.

WINNER! For simply sending in his question on unbacked veneer, Tom Vest of Maryland Heights, Missouri, wins a Steel City Model 25200 Bench Mortiser. Each issue we toss new questions into a hat and draw a winner.

Contact us by writing to "Q&A," Woodworker's Journal, 4365 Willow Drive, Medina, MN 55340, by faxing us at (763) 478-8396 or by emailing us at: QandA@woodwori<ersjoumal.com Please include your home address, phone number and email address (if you have one) with your question.

QI am new to woodworking but pretty good at building other things. I am building (or rather re-building) a large pantry cabinet in my kitchen, and I want to make sure it holds together this time. I thought about using a biscuit and dado for each joint. Is this advisable and, if so, how would I go about creating a biscuit slot within the dado?

Roland Schaer Richardson, Texas

AWhile the concept of reinforcing a joint is not out of the ordinary, adding a biscuit to a dado joint is one I've never heard of. It is common to reinforce a long dado joint with nails or screws (often taking the place of clamps when building the joint) but not biscuits. There are a couple of reasons for this: first, biscuits will not strengthen the joint. A well-made dado joint is remarkably strong, so adding the biscuit would simply introduce a degree of complexity with no clear benefit. Second, it would be tricky to get the biscuit slot cut into the bottom of a dado — not impossible, just really, really complicated. (After which I refer you back to my first point.)

— Rob Johnstone

Q Here's my two-part question: Why are there so many different screw head styles — i.e., Phillips head, slotted, star-shaped, hexagonal, etc.? And, how many screws are in a one-pound and five-pound box?

Robert Davenport Warren, Ohio

In a dado joint, a flat-bottomed slot is plowed into one of the pieces being joined together, to house the mating piece. A well-fitting dado joint is strong in use and generally easy to make in various ways.

A The primary reason for the wide variety of screw head drive types is to ensure the fact that you will never have the proper screwdriver close at hand when you need it. Now, with my spleen properly vented (punctured no doubt by a cheese-headed Torx drive ...), I will attempt a more reasoned response. Each different style of drive head (Phillips, spanner head,

Torx, tri-wing, etc.) was created to more effectively transfer energy (torque) from a drive mechanism (a flat-blade screwdriver, battery-powered drill/driver, Yankee screwdriver, etc.) to the screw — rotating it so that the threaded, cone-shaped shaft will twist into or out of a hole. All of the centered and symmetrical drive heads — Phillips being the prime example — were developed to work better with a ' mechanized drive system. (If you've ever tried to use a slotted screw with a powered drill/driver, you know why other styles were created. The slotted screwdriver bit slides out of the slot too easily when driven by mechanical power.)

When it comes to woodworking, just about any sort of drive head

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April 2009 Woodworker's Journal