DeWalt 340 Sanding Procedure, Fine Finishing, Removing Paint and Varnish, Cabinets and Doors

USING THE TOOL

SANDING PROCEDURE

The normal weight of the machine is sufficient for efficient sanding. Do not put additional pressure on the machine. This would only slow down the speed of the pad, reducing the sanding efficiency and put an additional burden on the motor. In addition, it might cause the sander to jump on the work. Let the sander do the work.

FINE FINISHING

The action of the Porter-Cable Finishing Sander causes thousands of tiny abrasive grits to move in circular orbits against the work at high speed. Each grain moves in the same direction at a constant speed so the cutting action is uniform over the entire pad surface. Crossing and re-crossing of the abrasive grits from all directions quickly levels surface irregularities to a fine, uniform smoothness. Start the work with an abrasive grit just coarse enough to remove the high spots and excessive roughness. Follow with a second sanding using a grit one or two grades finer. Continue with successively finer grits until the desired finish is obtained. DO NOT GO FROM A COARSE GRIT TO A VERY FINE GRIT IN ONE STEP.

Going from a coarse grit to a very fine grit in one step could make it difficult to remove swirl marks that might have been made by the coarse grit abrasive. Use the finest grits practical for the roughing operation and then finish by using successively finer grits.

REMOVING PAINT AND VARNISH

Read and follow all instructions in the "ADDITIONAL SAFETY RULES FOR PAINT REMOVAL" section of this manual.

Your sander will do a good job of removing old paint and varnish if two precautions are taken. First, be sure to use a coarse, open coat abrasive to avoid the usual clogging of the abrasive surfaces. Second, keep the machine moving over new areas to avoid heating and softening the material being removed. Try to work the entire surface down at the same time by working in wide, overlapping arcs. Do not concentrate on small areas. If liquid removers or heaters are used to speed the work, be sure the surface is cool and dry and the excess material has been scraped away with a putty knife or other suitable scraping tool before applying the sander.

CABINETS AND DOORS

The orbital motion of the Porter-Cable Finishing Sander is ideally suited for finishing doors, cabinet fronts and other installations where wood grain is often perpendicular to that of a joining piece. Since the motion is circular, the machine may be moved in any direction and crossed from one part to the other without regard to direction of grain. A uniform and smooth finish will result on both parts. The same procedure may be used when evening joints in all types of cabinet work. The sander may be worked on both sides and in all directions to obtain a smooth, matching joint. By properly changing from coarser to finer grit abrasives, an excellent finish will result.

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