SAWING

WITH THE BAND SAW

Here's how to choose the right blade, set up your saw and make the cut. Follow these simple instructions and soon you'll be slicing wood as thin as you please.

saw will adequately tension a wide blade. The problem is that the average 14" band saw just can't muster the force required to properly tension a ^V'-wide blade. So the best choice of blades is one your band saw can tension. I've gotten great results resawing with ³/s" and ¹/2" blades. Although this seems small for resawing, a narrow blade under sufficient tension performs much better than a wide blade with too little tension.

Selecting the Best Pitch

Pitch is the number of teeth per inch (TPI). Fine-pitch blades, those with a greater number of teeth, are the best choice for smooth cuts in relatively thin stock (less than 2"). In contrast, coarse-pitch blades, those with fewer teeth, are your best bet for resawing. It works like this: Behind each tooth is a space called a gullet. The gullets do the work of hauling the sawdust out of the kerf as the stock is cut. If the blade pitch is too fine, the small gullets quickly fill with sawdust and cutting slows dramatically. Also, the greater number of teeth that are

in contact with the stock at any given time, the more friction that's created at the tooth tip, causing overheating. Even worse, the blade may buckle and bow during the cut, distorting in the kerf and spoiling the stock.

To reduce vibration and increase the smoothness of the cut, manufacturers of band saw blades have begun to offer variable-pitch blades. As the name implies, the pitch of a variable-pitch blade changes repeatedly along the length of the blade. This unique tooth design limits the intensity of vibrations, resulting in a smoother surface that requires less cleanup. This is obviously a plus, especially when you are band sawing veneer.

Tooth Material

The teeth of a band-saw blade are subjected to tremendous heat and stress when resawing. Choosing the best tooth materi

al dramatically affects the life of the blade. Contrary to popular belief, the heat is generated by friction at the tooth tip, not by the blade guides. If you've ever used a cabinet scraper to smooth a board, you know how quickly the edge heats up and burns your thumbs. The same phenomenon occurs at the cutting edge of a band-saw blade. So don't expect to keep the blade significantly cooler by switching to a different type of guide. Instead, use the money to purchase a better blade.

Unfortunately, ordinary carbon-steel band saw blades quickly lose their temper and consequently their edge when subjected to the heat from resawing. Carbide, when compared to carbon steel, has much greater heat resistance and will retain its sharp edge much longer. As an added benefit, carbide-tipped band saw blades leave the surface smoother, too. That's because the teeth are precisely

by Lonnie Bird

ground after brazing to the blade. Although you're sure to get sticker shock the first time you price a carbide blade, just remember that they're more economical in the long run. As a rule, even though a carbide blade will cost 10 times more than a steel blade, it will typically hold its edge 25 times longer.

Tooth Type

Flip through the pages of a catalog and you'll see that band saw blades are available in three tooth types: regular, skip and hook.

My favorite blade is this Lenox ³/s^M-wide variable-pitch blade. It has a 2/3 variable-tooth-pitch hook tooth that is carbide-tipped. It cuts smoothly and aggressively and lasts a long time. For more information on this blade, go to www.lenoxsaw.com or call 800-628-8810.

Lonnie Bird (www.lonniebird.com) is author of "The Bandsaw Book" (The Taunton Press). He builds period furniture and conducts woodworking seminars in Dandrige, Tennessee.

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