Creative Woodworks & crafts 2004-06, страница 19

Then there are the spiral blades that cut from any side because the teeth are wrapped around the whole blade. When using this blade, you can move the wood left, right., forward, or back to make the cut. With other blade types, the cutting is on the front, side of the blade only, so the wood has to be rotated to make the cuts. Many scrollers like spiral blades, while others can't seem to control them. They are the only way to make cuts in wood that is too long to turn on the saw, so there are special cuts that only this type of blade will do.

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Creative Woodworks S Crafts June 2UU4 • 13

Noticc the burn marks on the first and third pieces from the left. These burns resulted from the use of reverse tooth blades. Sawdust seems to build up in the gap where the teeth reverse direction, and can then cause the burn. Pieces 2 and 4 were cut with the PGT blades and do not usually burn like that. The biggest drawback to these blades is the cost. They cost about double the price of the skip tooth blades, so many scrollers choose not. to use them.

Some Other Options

Since the advent of PGT blades, a larger selection of blades has become available. The newest styles arc the Flying Dutchman and Olson Ultra blades. These blades are a cross between the skip tooth and the PGT and many people like them and do all of their cutting with them. Others find that they cut a little loo aggressively and leave a bigger hole at the corners and turns. The bigger hole is due partially to the fact that these blades are a little wider front to back than the skip tooth blades.

Sometimes, the blade wanders too hard to the right and it is not caused by tension or feed rate, but by the blade itself. If you look closely at the bottom blade in the photo above, you can see a larger burr on it than the one on the top. This blade cut a good 30" to the right from a straight line. There is no way you can cut anything with a bad blade like this; just throw it away and hope that there aren't any similar ones in the pack!

Spiral Blades

Crown Tooth Blades

There arc also many other blade designs from which to choose. There are the crown tooth and 2-vvay cut types, which can be used with either end down, because the teeth face both directions. Tn general, we know that a scroll saw blade has a tendency to wander to the right because of the burr on the right side. Crown tooth blades are made the same way, and have the same drift factor. So when the blade is in the saw the correct way, it works like a normal blade with the right-hand drift, but when we turn it over, the drift now goes to the left. This can be a little difficult to get used to, but can be compensated for once you understand the cause.