I've got a Sears Contractor jointer (6 years old) which has given me
pretty good service over the years.

Lately, however, it has lost alignment and I can't seem to recover it.
Run a board over it and the resultant edge is proud in the center.
Perfect for cawls but not very useful for gluing up panels. Very
symetrical, incidentally.

I've adjusted the blade height several times to no avail. One of the
problems is there is an amazing amount of backlash in the outfeed table
adjustment so setting it is problematic at best. Anyone have any
suggestions as to what I might do differently. New jointer isn't an
option right now.

tnx

wrote:


Run a board over it and the resultant edge is proud in the center.
Perfect for cawls but not very useful for gluing up panels. Very
symetrical, incidentally.

I've adjusted the blade height several times to no avail. One of the
problems is there is an amazing amount of backlash in the outfeed table
adjustment so setting it is problematic at best.

I'm guessing it is NOT a blade height problem--I don't see how that
can create a cut proud in the middle. I'd suspect non-coplanar tables.
Raise the infeed table to the same height as the outfeed, and after
rotating the blades out of the way, put a long straight-dedge across
the tables. If the outer ends of the tables are high, this would cause
the cut I understand you to be getting. If the gibs on the outfeed
table are out of adjustment or loose, that might account for slop in
the outfeed table movement (although I can't picture the mechanism
well, and can't figure how it could cause backlash).

Another technique, if you don't have a dependable long straightedge,
is to get two plastic draftsman's triangles, put one on each table and
see if the vertical sides meet perfectly.
--
Alex -- Replace "nospam" with "mail" to reply by email. Checked infrequently.

alexy wrote:
I'm guessing it is NOT a blade height problem--I don't see how that
can create a cut proud in the middle. I'd suspect non-coplanar tables.

elided

--
Alex -- Replace "nospam" with "mail" to reply by email. Checked infrequently.

Infeed and outfeed were WAY out of parallel and the infeed was lower
next to the blades. That would explain the curve I was seeing.

They're now parallel and edges are straight (at least to 2 mils).

tnx for the suggestions.