Sanding medium – Metabo Wood Sanding Machine User Manual
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SANDING MEDIUM
A quality machine also needs a quality accessory. For
sanders a wide range of accessories are required to give
the best finish for a wide range of materials. Be it for
wood, metal, stone, paint, varnish or filler Metabo has the
right accessory for the machine and the material.
At Metabo we do not just make accessories for our own
machines but for other manufactures as well.
SOUND ARGUMENTS.
The sanding compound
carries the grains and transfers the chip removal forces. Besides high 
strength and small expansion, the sanding compound has to render 
a sanding process matching flexibility .
Carriers are
– Highly compressed papers of various thicknesses.
– Fabric based on polyester and cotton wool of various strengths.
– 
Vulcanized fibre as a strong and tear-proof base is the base 
material for the (Vulcan) fibre disc.
The abrasive grain
is the actual sanding tool. It penetrates the material to be worked on 
and removes the surface. The abrasive grain is anchored on the grain-
holding medium. High hardness, toughness and a sharp edged 
geometry are the most important attributes of the abrasive grain.
For top quality sanding medium only synthetic abrasive grain materials 
are used.
Abrasive grain types are
– 
Corundum (Aluminiumoxide) as a hard, slightly brittle grain 
for the processing of metal, wood, lacquers.... of rough- and 
fine ground finishes.
–
Silicon carbide as a hard, sharp-edged abrasive grain for 
processing of lacquer, wood, ceramic, glass, rubber... for rough 
and fine ground finish.
–
Aluminous zircon as a tough and fine crystalline combination 
of Aluminiumoxide and aluminous zircon for the processing 
of metal and non-rusting materials.
The bonding agent
anchors the abrasive grain in the sanding compound carrier and 
supports it against the forces generated by the removal of the 
surface material.
Bonding agents are
– 
Phenolic resins and partially synthetic resins for sufficient 
support with a certain elasticity.
Sanding compound carrier: Paper, fabric, fibre or a 
P-G-combination
Abrasive grain
(Corundum,
silicone 
carbide)
Covering
bonding
material
(Phenolic resin)
More 
grind-
active
Coat
Basic
bond
(Phenolic
resin)
Structure and purpose of Metabo abrasive mediums