"George Max" wrote in message
...

I bought a planer because it's possible to use it as a jointer



Wrong. It is *never* possible to use a planer as a jointer.

Wrong, tell that to the 200 BF of 8' long oak I have that was all rough cut
and not perfectly flat or straight.


The two machines serve completely different functions.

From the factory, yes. With a jig, no.


The fence on the jointer is used to make one of the edges adjacent to that
flat face perpendicular to it.

On long boards this is easier and faster on a TS with a jig.

Various
adjustments to the tables and fence on a jointer can vary the results
from flat and perpendicular.

True

The reason a planer cannot joint is that the pressure of the feed
rollers can temporarily flatten the board so that it gets planed, but
the board returns to it's formerly cupped/twisted/warped original
shape after that pressure is relieved. Of course, if you're board is
"flat enough" or you otherwise use any clever jigs or other
contraptions to hold your board as it goes through the planer, you
*might* get away with making the surfaces flat and reasonably parallel
to each other.

You mention flat enough. If your board is not "flat enough" you should not
even consider using a jointer to flatten it. There will simply be too much
waste. Better to rip the piece on a band saw to get rid of most of the cup
or cross cut to a shorter length to get rid of most of the bow.
The planer jigs work really well.