|I started work on a project for a
Christmas present last weekend, and was in the process of cutting some big
boards down to size when I realized that my saw wasn't cutting very well. I
took a look at the saw blade, and was I surprised. What a mess.
I can't believe I didn't notice it before. But this sort of thing happens so
slowly that you don't even realize it's happening.
If I were doing things right, before starting a project, I'd check the angle of
the blade to the miter gauge. They must be precisely 90 degrees for clean
But a perfectly adjusted saw doesn't guarantee perfect cuts. That's the job of
the cross-cut blade, and there are a couple of things to check. Start with the
The condition of the teeth will determine if the blade cuts cleanly or leaves
ragged or chipped-out edges. No blade will cut well if the teeth are all gunked
up with pitch and resin. So, if necessary, I soak the blade in a pizza pan
filled with commercial blade cleaner.
When the blade is clean, I use a magnifier to look closely at the teeth (a 30X
illuminated pocket microscope -- about $10 at Radio Shack). Check the top,
front, and edges of a few teeth.
Each tooth has two cutting edges. The first is where the top and front surfaces
of the tooth come together. And the second is where the side(s) and front of
the tooth come together. These edges are where the actual cutting takes place.
If the edges look beat up or ragged, it's probably time to have the blade
sharpened. But just to be sure, make a test cut. If the blade is really dull,
it will show up on the wood. So take a good close look at the cut.
What really matters is the look and feel of the cut off piece. So I take a
piece of scrap and cut a 3" piece off one end. If the teeth are sharp,
there shouldn't be any chip out or raggedness on any of the edges.
Next examine the cut-off end. The end should look shiny and feel like it's been
sanded. You can see this best when holding the end up to a bright incandescent
light. If the blade is dull, you'll be able to see rough tooth marks or burns.
So if the cut surface isn't clean and shiny with sharp edges, consider
sharpening the blade.
Go to Tip #36