Recently, any time I tried to flatten one side of a board, my jointer
would start the cut OK but would remove less wood on the last 2/3 of
the board. Eventually my board was wedge-shaped with the front edge
narrower than the rear. I knew this is caused by the infeed and
outfeed tables not being parallel. To get a true read on how much they
are off you need to use a perfect straightedge the length of both
tables. A good method of making a straight "test bar" is in Fine
Woodworking issue 142. I checked all the other adjustments, blade
height, gib screws, table height, etc, and they were all OK. I was
going to shim my outfeed but I was puzzled as to how two perfectly flat
tables can go out of parallel. After all, how much wear can occur in
the gib and dovetail areas from the minor amount of table height
adjusting done on a normal basis? Instead, I removed both of the
tables and cleaned the gibs and dovetail areas. I reassembled and
tested. It worked perfectly. Something, most likely sawdust, must
have built up in the top edges of the dovetails to cause the out of
parallel condition. Shimming the table would have also fixed the
problem but all I would have been doing was compensating for dirty
gib/dovetails.
Dave
That can also happen when your outfeed table is slightly above your
blade height.
bc
[email protected] wrote:
> Recently, any time I tried to flatten one side of a board, my jointer
> would start the cut OK but would remove less wood on the last 2/3 of
> the board. Eventually my board was wedge-shaped with the front edge
> narrower than the rear. I knew this is caused by the infeed and
> outfeed tables not being parallel. To get a true read on how much they
> are off you need to use a perfect straightedge the length of both
> tables. A good method of making a straight "test bar" is in Fine
> Woodworking issue 142. I checked all the other adjustments, blade
> height, gib screws, table height, etc, and they were all OK. I was
> going to shim my outfeed but I was puzzled as to how two perfectly flat
> tables can go out of parallel. After all, how much wear can occur in
> the gib and dovetail areas from the minor amount of table height
> adjusting done on a normal basis? Instead, I removed both of the
> tables and cleaned the gibs and dovetail areas. I reassembled and
> tested. It worked perfectly. Something, most likely sawdust, must
> have built up in the top edges of the dovetails to cause the out of
> parallel condition. Shimming the table would have also fixed the
> problem but all I would have been doing was compensating for dirty
> gib/dovetails.
>
> Dave
I agree that a slight wedge shape can be normal while flattening one
side. But this was extreme. By the time I surfaced one side I had
already lost over 1/4" of a 4/4" board. After the first few passes I
knew something was wrong. There are times when shims are the only way
to make the tables parallel. The purpose of my post was to alert guys
that you might want to clean the dovetails before shimming.
Swingman wrote:
> <[email protected]> wrote in message
>
> > Recently, any time I tried to flatten one side of a board, my jointer
> > would start the cut OK but would remove less wood on the last 2/3 of
> > the board. Eventually my board was wedge-shaped with the front edge
> > narrower than the rear.
>
> This is not uncommon, even with a well setup jointer. Despite the "wedge"
> shape, was the jointed surface of the board flat?
>
> If so, that's all you can expect from the jointer.
>
> To get rid of the wedge shape, and make the opposite surface/edge parallel
> to the jointed surface/edge, enter a planer for the surfaces, and the well
> setup table saw/fence for edges.
>
> --
> www.e-woodshop.net
> Last update: 12/13/05
Thanks for the post, Dave. I just purchased a used 8" jointer, and
removed the infeed table for transport (and weight reduction). I'll be
cleaning up the ways and gibs before reattaching (may or may not remove
the outfeed table ...)
I was doing some edge jointing on my router table a month or so ago was
getting this same behaviour - wedge shape forming. Turns out the two
faces of my fence weren't perfectly coplaner because there was the
slightest bit of schmutz (sp?) on the shim stock for the outfeed fence
face.
Regards,
Chris
There is a book out by the shop foreman for FWW. The title is
something like "setting up 5 basic power machines". I took it out
at the local library. His section on the jointer would be worth
purchasing the book. I had shimmed and diddled with my old 6"
Rockwell until it was unusable. I used his directions, took the
machine apart and cleaned and reassembled as per his suggestions.
It is running absolutely great. Would highly recommend.
______________________________
Keep the whole world singing . . . .
DanG (remove the sevens)
[email protected]
<[email protected]> wrote in message
news:[email protected]...
> Recently, any time I tried to flatten one side of a board, my
> jointer
> would start the cut OK but would remove less wood on the last
> 2/3 of
> the board. Eventually my board was wedge-shaped with the front
> edge
> narrower than the rear. I knew this is caused by the infeed and
> outfeed tables not being parallel. To get a true read on how
> much they
> are off you need to use a perfect straightedge the length of
> both
> tables. A good method of making a straight "test bar" is in
> Fine
> Woodworking issue 142. I checked all the other adjustments,
> blade
> height, gib screws, table height, etc, and they were all OK. I
> was
> going to shim my outfeed but I was puzzled as to how two
> perfectly flat
> tables can go out of parallel. After all, how much wear can
> occur in
> the gib and dovetail areas from the minor amount of table height
> adjusting done on a normal basis? Instead, I removed both of
> the
> tables and cleaned the gibs and dovetail areas. I reassembled
> and
> tested. It worked perfectly. Something, most likely sawdust,
> must
> have built up in the top edges of the dovetails to cause the out
> of
> parallel condition. Shimming the table would have also fixed
> the
> problem but all I would have been doing was compensating for
> dirty
> gib/dovetails.
>
> Dave
>
<[email protected]> wrote in message
> Recently, any time I tried to flatten one side of a board, my jointer
> would start the cut OK but would remove less wood on the last 2/3 of
> the board. Eventually my board was wedge-shaped with the front edge
> narrower than the rear.
This is not uncommon, even with a well setup jointer. Despite the "wedge"
shape, was the jointed surface of the board flat?
If so, that's all you can expect from the jointer.
To get rid of the wedge shape, and make the opposite surface/edge parallel
to the jointed surface/edge, enter a planer for the surfaces, and the well
setup table saw/fence for edges.
--
www.e-woodshop.net
Last update: 12/13/05
On 1 Mar 2006 05:08:27 -0800, [email protected] wrote:
>adjusting done on a normal basis? Instead, I removed both of the
>tables and cleaned the gibs and dovetail areas. I reassembled and
>tested. It worked perfectly. Something, most likely sawdust, must
>have built up in the top edges of the dovetails to cause the out of
>parallel condition.
Petty common maintenance issue especially with a lot of use.
>Shimming the table would have also fixed the
>problem but all I would have been doing was compensating for dirty
>gib/dovetails.
Assuming a quality machine to start with, it would take a lot of
moving of the tables to wear out the dovetails. I've seen 50 year old
joiners, that once cleaned up, have tables that are still quite good
to each other.
Mike O.