JET Tools 608003 User Manual - Page 22

Sanding Imperfect Stock When sanding stock with a cup or crown, place the crown up. This will stabilize the stock to help prevent tipping or rocking during sanding. (After the crown has been removed and the top is flat, turn the stock over and sand the opposite side.) To avoid personal injury, take special care when sanding stock that is twisted, bowed, or otherwise varies in thickness from end to end. If possible, support such stock as it is being sanded to keep it from slipping or tipping. Use extra roller stands, help from another person, or hand pressure on the stock, to minimize potentially hazardous situations. Face Frames and Raised Panel Doors It is very important to have the proper abrasive contact when doing this type of sanding. If the machine is set to take an excessive depth of cut, the result can be a gouge or dip as the drum goes from sanding the rails at full width to sanding just a few inches of width on the stiles. To prevent this, make sure that when using abrasives finer than 80 grit the drum is in contact with the wood but can still be spun by hand. If there is room, angling the stock on the conveyor belt can also help. Slowing the conveyor feed when coming to a rail in the stock can help prevent a dip or gouge. This allows the abrasive to work the wider width with less effort, and to achieve better consistency of the finished surface. Stock Feeding Angle Some pieces, because of their dimensions, will need to be fed into the machine at a 90° angle (perpendicular to the drums). However, even a slight offset angle of the stock will provide for more effective stock removal. The optimum feeding angle for stock removal is about 60° (see Figure 32). mineral streaks in the stock, more even wear of abrasive strips, potentially faster feed rates, and lighter loads on the motor. Note that to get the best final finish, however, the stock should be fed through the machine so it will be sanded in line with the grain of the wood on the final one or two passes. Keeping the Machine Clean For best results, make cleaning the machine a regular shop procedure. Allowing excess buildup of dust and debris can adversely affect performance through the loading of the abrasives, slippage on the conveyor table, and/or the accumulation of material inside the drums which can throw off the center of balance. Leave the dust collector on when cleaning dust from the drums. Also brush the conveyor belt after cleaning operations. If not cleaned, the conveyor belt could allow stock to slip during sanding operations. Maintenance Before doing maintenance on the machine, disconnect it from the electrical supply by pulling out the plug or switching off the main switch! Failure to comply may cause serious injury. For best results, perform the following recommended procedures on a monthly basis: • Lubricate conveyor bushings and check for wear. • Lubricate all moving parts, such as threaded rods, washers, and bushings. (Bearings are pre-sealed and require no lubrication.) • Clean sawdust from the abrasive strip and the conveyor belt. • Blow dust from motors and switches. Blow dust from inside of sanding drum. • Check all set screws for tightness on parts such as bearings, conveyor and couplings. Figure 32 Angling the workpiece for stock removal provides other advantages, such as less loading of certain areas of the drums due to glue lines or 22