Q: We are getting a lot of chipped grain with our newly purchased (used) planer. Our knife angles seem okay. We are feeding at 45 fpm which is quite slow. Can you help?
A: To be helpful in solving this problem, someone has to be there to see what exactly is going on. However, from the samples that you sent, the defect is not chipped grain but is actually an edge splitting problem. This problem occurs only when the grain at the edge is at a 45 degree angle. The knife has a choice of cutting off the wood or pushing it away.
With oak lumber when the grain is 45 degrees at the edge, it is easier (especially with a dull knife, excessively deep cut, very slow cut, or poor clearance angle) to push the wood out of the way. Over-dried lumber or excessive pressure from the chip breaker or pressure bar can also accentuate the problem.
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