Jet SandSmart 22-44 Pro, Operating And Parts Manual

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Abrasive Selection Guide
Grit Common Application
24........ Abrasive planing, surfacing rough-sawn boards, maximum stock removal, glue removal.
36........ Abrasive planing, surfacing rough-sawn boards, maximum stock removal, glue removal.
50........ Surfacing and dimensioning boards, trueing warped boards
60........ Surfacing and dimensioning boards, trueing warped boards.
80........ Light dimensioning, removal of planer ripples.
100...... Light surfacing, removal of planer ripples.
120...... Light surfacing, minimal stock removal.
150...... Finish sanding, minimal stock removal.
180...... Finish sanding only, not for stock removal.
220 ..... Finish sanding only, not for stock removal.
Abrasives
The abrasive material you choose will have a
substantial effect on the performance of your
sander. Variations in paper type, weight, coating
and durability all contribute to achieving your
desired finish.
JET Abrasives are available in Ready-To-
Wrap
TM
pre-cut lengths or in the convenient
Ready-To-Cut pre-marked box. Your JET dealer
can recommend the best choice for your
application.
Selecting Drum Abrasives
It is important to select the proper grit of
abrasive for the type of sanding being performed
to achieve maximum results. As with any
sanding operation, first begin sanding with a
coarser grit, depending upon the roughness of
the stock or the amount of stock to be removed.
Then progressively work toward finer grits. The
chart (Figure 44) shows the general uses for the
various grits. JET offers abrasives in the ten
different grits shown – consult the stock
numbers on page 32 to order.
The amount of stock to be removed is a major
consideration when choosing the grit grade with
which to begin. Grits 24, 36, 50 and 60 are
primarily designed for stock removal. Grits 24
and 36 will remove the most material in one
pass, whether you are doing abrasive planing,
cleaning up glued panels, or flattening stock.
Grits from 100 through 220 are primarily
finishing grits designed to remove the scratch
pattern from the previous grit used. For best
results, never skip more than one grit grade
when progressing through a sanding sequence.
For fine work, such as furniture, try not to skip
any grit grades during the sanding process.
In general, premium quality abrasives will
produce a better finish with a less noticeable
scratch pattern.
NOTE: Grits that are too fine can sometimes
burnish the wood and leave a glossy surface
which will not accept stains evenly. This will vary
by type of wood. Oak, for example, is
susceptible to burnishing because of its open
pores.
Cleaning Abrasive Strips
Regularly clean the abrasive strips on the drums
with commercially available cleaning sticks,
following the manufacturer’s directions. When
cleaning, also brush the stick crumbs from the
drum while it is still rotating.
In some cases, build-ups resulting from burns
can also be removed with Plexiglas held on
edge over the rotating drum.
Always wear eye protection
while performing sandpaper cleaning, and
take all precautions to avoid any contact of
hands or clothing with the rotating drum.
Cloth-backed abrasives can be cleaned by
soaking in paint thinner or mineral spirits for 20
minutes to 1 hour, then using a brush to remove
any build-up. Dry the abrasive strips completely
before using. Any used solvents should be
discarded in compliance with environmental
regulations.
Increasing Abrasive Life
Abrasive life can be increased not only by
cleaning, but by removing the abrasive strip from
the drum and reversing it. To do this, remove the
strip and use what was the trailing end as the
starting end on the left (outboard) side of the
drum. Reversing the strip will provide a fresh set
of cutting edges on the abrasive.
Figure 44