Using The Tool - Porter Cable 340 Manual De Instrucciones

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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