Air Board File or Inline Sander
Precautions: Use safety glasses and a dust mask with this tool. This sander is to be used flat against the surface not on end or on the edges, this type of misuse will damage the pad and gears. Inlet pressure should be no greater than 90 psi.
Usage: The inline sander is named after its inline, back and forth, motion. They are typically used to sand, cut, and shape filler materials. The board file is one of the tools used for the initial cutting of fillers and use 36-40 grit sandpaper for this operation. They can also be used with finer grit papers if desired.
Six Inch Dual Action Sander or DA
Usage: The DA sander is used on painted surfaces that require leveling. It should be kept flat to the surface, any lifting of an edge will dig a hole and create a bulls eye when painted over. The DA oscillates and Spins thus the dual action. There are three main pattern sizes each DA has a specific patter built in, some have a very fine oscillating pattern, others large, the larger the oscillating pattern the more aggressive the cutting action and courser grit paper is used. Note, the beginner should never use a DA directly over filler materials, it is too easy to create flat spots and dish out the filled surface.
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Six vs Eight Inch Dual Action Sander or DA
Usage: This picture is a comparison of the six inch dual action sander to the eight inch dual action sander.
Eight Inch Dual Action Sander / Mud Hog
Usage: Many refer to this tool as the Mud Hog because it is very aggressive and is typically used to sand, cut, and shape body fillers. You will recall the inline sander does the same job, the basic differences are in the aggressiveness between the two. NOTE, the Mud Hog is the most aggressive and the hardest to control, the Inline Sander is next aggressive and is easier to control, the hand board sander is the least aggressive but has the most control.
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