Wood Characteristics
Below is a list of wood characteristics you may encounter when planing. The following descrip- tions of defects will give you some possible answers to problems you may encounter while planing different materials. Possible solutions fol- low the descriptions.
Chipped Grain
Problem: Usually a result of cutting against the grain, planing lumber with knots or excessive amount of cross grain, or using dull knives.
Solution: Decrease depth of cuts. Inspect your lumber and determine if its grain pattern is caus- ing the problem. If the lumber does not show sub- stantial crossgrain, replace your knives.
Fuzzy Grain
Problem: Usually caused by surfacing lumber with too high of a moisture content. Sometimes fuzzy grain is an unavoidable characteristic of some woods, such as basswood. Fuzzy grain can also be caused by dull knives.
Solution: Check the lumber with a moisture meter. If moisture is greater than 20%, sticker the lumber and allow it to dry. Otherwise, inspect the knife condition.
Snipe
Problem: Occurs when board ends have more material removed than the rest of the board. Usually caused when the workpiece is not prop- erly supported as it goes through the machine. In many cases, however, a small amount of snipe is inevitable.
Solution: The best way to deal with snipe is by planing lumber longer than your intended work length and then cutting off the excess after plan- ing is completed.
G0663 12½" Planer
Pitch & Glue Build-up
Problem: Glue and resin buildup on the rollers and cutterhead will cause overheating by decreasing cutting sharpness while increasing drag in the feed mechanism. The result can include scorched lumber as well as uneven knife marks and chat- ter.
Solution: Clean the rollers and cutterhead.
Chip Marks or Indentations
Problem: Chip indentation or chip bruising is the result of wood chips not being thrown away from the cutterhead and out of the machine. Instead they are carried around the cutterhead, deposited on the planed surface and crushed by the outfeed roller. Chip indentations can be caused by a num- ber of reasons, some of which are:
•The type of lumber being planed. Certain species have a tendency to chip bruise.
•A high moisture content (over 15%) or surface moisture. Typically found in air- dried stock where the surface is dry but the inside needs a longer time to sea- son.
•Dull knives.
•Too much material being removed in one pass.
Solution:
•Lumber must be completely dry, prefer- ably
•Make sure planer knives are sharp.
•Reduce depth of cut.
