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Avoid table saw burn marks
Every time I make a cut on my tablesaw, I get burn marks on my stock. What can I do to stop this? - Jim See, Kingston, Ont.
The burning is caused by the friction of the blade against the wood, and can generally be attributed to one of three main causes.
1. A dull or dirty blade. The first step is to make sure the blade is sharp. Sharp blades cut away the material, while a dull blade tends to wear it away. The result is the same, but the heat gener-ated by the dull teeth ploughing through the material will cause scorching during the cut. If your blade seems sharp, check to ensure it’s clean. Pitch and resin have a tendency to build up behind the carbide teeth and cause poor cuts and heat buildup. Often, what seems to be a dull blade can be brought back to cutting like new with just a cleaning. There are many blade cleaners available, both commercial and homemade, that will make quick work of removing the deposits.
2. Fence alignment. If your fence is not perfectly parallel to your blade, the stock will push sideways against the blade as it is fed through. Check the alignment of your fence by putting a straightedge, such as a ruler, against the blade and ensuring that it is touching a tooth at both ends. Slide the fence over until it touches the ruler and check for gaps at either end. If a gap is present, you need to adjust the fence.
3. Technique. Different woods require different feed speeds through the saw to avoid burning. Woods such as cherry and soft maple have a tendency to burn even with a sharp blade and good alignment. Try feeding these burn-prone woods through the saw faster to reduce heat buildup and burning. Also, make sure that the edge of the board riding against the fence is perfectly straight, as even a slight bow will cause the wood to bind against the blade partway through the cut and cause burning or kickback.