I (finally) bought an 8" "General International" jointer but
I've been having problems with my cuts; the work piece gets
progressively narrower or thinner - I've been getting 1/32" -
3/64" per 7'. After most of a weekend working on this I am
baffled. I understand that an outfeed table set too high can cause
this. So I tried setting it at several levels, including one so low to
the knives that it sniped at the end of the piece and still got a
taper. I also tried to finesse it by bearing down harder at the start
of the cut, then backing off on the pressure towards the end. This
knocked off about 1/64" but still resulted in a taper. I've worked
with a few industrial strength jointers in a wood class and in a mill
but never seemed to have this kind of problem. Then again, I never
measured the result quite so closely.
Could I have done something wrong with the set-up? Is there some kind
of flaw with the jointer? Or is 1/32" - 3/64" within normal
tolerances?

I'd really appreciate any comments and suggestions.

Check that the outfeed table isn't too high at the far end, meaning the
two tables aren't parallel. That's the scenario that would result in a
progressively deeper cut. Either shim the ways or return the unit.

This assumes that your technique is correct; transfer pressure to the
outfeed table instead of bearing down on the infeed side as you joint
your boards. You've used other units with no problem, so I think the
tables aren't parallel.

Dave



spalted wrote:

I (finally) bought an 8" "General International" jointer but
I've been having problems with my cuts; the work piece gets
progressively narrower or thinner - I've been getting 1/32" -
3/64" per 7'. After most of a weekend working on this I am
baffled. I understand that an outfeed table set too high can cause
this. So I tried setting it at several levels, including one so low to
the knives that it sniped at the end of the piece and still got a
taper. I also tried to finesse it by bearing down harder at the start
of the cut, then backing off on the pressure towards the end. This
knocked off about 1/64" but still resulted in a taper. I've worked
with a few industrial strength jointers in a wood class and in a mill
but never seemed to have this kind of problem. Then again, I never
measured the result quite so closely.
Could I have done something wrong with the set-up? Is there some kind
of flaw with the jointer? Or is 1/32" - 3/64" within normal
tolerances?

I'd really appreciate any comments and suggestions.

"spalted" wrote in message
oups.com...
I (finally) bought an 8" "General International" jointer but
I've been having problems with my cuts; the work piece gets
progressively narrower or thinner - I've been getting 1/32" -
3/64" per 7'. After most of a weekend working on this I am
baffled. I understand that an outfeed table set too high can cause
this. So I tried setting it at several levels, including one so low to
the knives that it sniped at the end of the piece and still got a
taper. I also tried to finesse it by bearing down harder at the start
of the cut, then backing off on the pressure towards the end. This
knocked off about 1/64" but still resulted in a taper. I've worked
with a few industrial strength jointers in a wood class and in a mill
but never seemed to have this kind of problem. Then again, I never
measured the result quite so closely.
Could I have done something wrong with the set-up? Is there some kind
of flaw with the jointer? Or is 1/32" - 3/64" within normal
tolerances?

It really sounds like you are expecting the jointer to do what it was not
designed to so.
IF the board ends up with a curved edge or surface, the out feed table
adjustment is probably the culprit.
IF the edge or surface that you are running through the jointer is "straight
and flat" after the pass regardless of how that edge or surface compares to
the opposite surface or edge, it is working correctly. A jointer is not to
be used to make parallel edges or surfaces. Opposite parallel edges and
surfaces are acquired by using a table saw and thickness planer
respectively.

I didn't get from his post the same thing you did, Leon. What I got was
that the jointer is making a tapered cut, which WILL happen either if
the outfeed is too high (progressively SHALLOWER cut), or if the outfeed
table isn't parallel, but sits high at the far end, in which case you'll
get a progressively DEEPER cut. I agree you don't use a jointer to make
parallel surfaces, but you also don't want the jointer to whittle away
more of the wood from one end than the other, either!

Dave

Leon wrote:

"spalted" wrote in message
oups.com...

I (finally) bought an 8" "General International" jointer but
I've been having problems with my cuts; the work piece gets
progressively narrower or thinner - I've been getting 1/32" -
3/64" per 7'. After most of a weekend working on this I am
baffled. I understand that an outfeed table set too high can cause
this. So I tried setting it at several levels, including one so low to
the knives that it sniped at the end of the piece and still got a
taper. I also tried to finesse it by bearing down harder at the start
of the cut, then backing off on the pressure towards the end. This
knocked off about 1/64" but still resulted in a taper. I've worked
with a few industrial strength jointers in a wood class and in a mill
but never seemed to have this kind of problem. Then again, I never
measured the result quite so closely.
Could I have done something wrong with the set-up? Is there some kind
of flaw with the jointer? Or is 1/32" - 3/64" within normal
tolerances?


It really sounds like you are expecting the jointer to do what it was not
designed to so.
IF the board ends up with a curved edge or surface, the out feed table
adjustment is probably the culprit.
IF the edge or surface that you are running through the jointer is "straight
and flat" after the pass regardless of how that edge or surface compares to
the opposite surface or edge, it is working correctly. A jointer is not to
be used to make parallel edges or surfaces. Opposite parallel edges and
surfaces are acquired by using a table saw and thickness planer
respectively.

"David" wrote in message
...
I didn't get from his post the same thing you did, Leon. What I got was
that the jointer is making a tapered cut, which WILL happen either if the
outfeed is too high (progressively SHALLOWER cut),

Too high, the board tends to have a convex bow on the side run through the
cutter. Too low and the board tends to have a concave bow on the side run
through the cutter. The out feed table is not used to create a taper.



or if the outfeed
table isn't parallel, but sits high at the far end, in which case you'll
get a progressively DEEPER cut. I agree you don't use a jointer to make
parallel surfaces, but you also don't want the jointer to whittle away
more of the wood from one end than the other, either!

It is almost impossible to prevent straight line taper on a jointer because
the human hand does not provide a very good solid index constant like the
table on a thickness planer or the fence on a TS. With lots of practice and
fewer passes through the jointer you can keep the taper to a minimum. If
the board is not straight to start with a taper is hard to avoid.

You are miles off tolerance. This is a common setup problem. Your manual
should explain how to correct this. The input table and output tables are
out of plane. The infeed table must be lower than the outfeed but still
must be in same plane.

On 23 May 2005 12:28:34 -0700, "spalted" wrote:

I (finally) bought an 8" "General International" jointer but
I've been having problems with my cuts; the work piece gets
progressively narrower or thinner - I've been getting 1/32" -
3/64" per 7'
============snip snip snip.===========

Once I pass the blades almost all of the pressure I "put" downward on
the board is on the outfeed table... almost nothing on the infeed side
of the blades... But no matter how good your technique is if the
tables are not co-planer... ya got problems...

Like others have noted . cutting on a taper suggests to me that your
outfeed table is NOT co-planer to the infeed ...thus the end (of the
outfeed) table may be slightly higher or lower then the leading edge
of the outfeed table...

I have been using an old Rockwell jointer for close to 40 years and
the outfeed table is fixed...no adjustments possible ..except maybe a
machine shop...

The first few months I had it I blamed the poor results on my newbie
techique...Visited my Dad one weekend and I mentioned my problems
and a quick visit to his shop proved my technique was ok... When I
got home I had to shim the infeed table ....that adjustment held for
over 20 years before I had to re-shim the infeed table,...

Honestly I do not know how badly I could have screwed it up if both
tables were adjustable as most of them are,...

Lots of luck...

Bob Griffiths

"Leon" wrote in message
m...

"David" wrote in message
...
I didn't get from his post the same thing you did, Leon. What I got was
that the jointer is making a tapered cut, which WILL happen either if the
outfeed is too high (progressively SHALLOWER cut),

Too high, the board tends to have a convex bow on the side run through the
cutter. Too low and the board tends to have a concave bow on the side run
through the cutter. The out feed table is not used to create a taper.



or if the outfeed
table isn't parallel, but sits high at the far end, in which case you'll
get a progressively DEEPER cut. I agree you don't use a jointer to make
parallel surfaces, but you also don't want the jointer to whittle away
more of the wood from one end than the other, either!

It is almost impossible to prevent straight line taper on a jointer
because
the human hand does not provide a very good solid index constant like the
table on a thickness planer or the fence on a TS. With lots of practice
and
fewer passes through the jointer you can keep the taper to a minimum. If
the board is not straight to start with a taper is hard to avoid.



This is why I usually make two light passes flipping the board end to end
between passes.
Mis-aligned tables will indeed result in curved edges, not "tapered but
straight"

That will help, IF the wood isn't tear-out prone in one direction.

Dave

TaskMule wrote:




This is why I usually make two light passes flipping the board end to end
between passes.
Mis-aligned tables will indeed result in curved edges, not "tapered but
straight"

In article , "Leon" wrote:

It is almost impossible to prevent straight line taper on a jointer because
the human hand does not provide a very good solid index constant like the
table on a thickness planer or the fence on a TS. With lots of practice and
fewer passes through the jointer you can keep the taper to a minimum. If
the board is not straight to start with a taper is hard to avoid.

You're missing the point, Leon. The unavoidable slight taper you're talking
about is on the order of a few thousandths of an inch over three or four feet,
if the jointer is set up properly and the operator's technique is good.

The OP is seeing _an_order_of_magnitude_ more taper than that. 3/64" over
seven feet is WAY TOO MUCH.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?

"Doug Miller" wrote in message
. ..
In article , "Leon"


You're missing the point, Leon. The unavoidable slight taper you're
talking
about is on the order of a few thousandths of an inch over three or four
feet,
if the jointer is set up properly and the operator's technique is good.

The OP is seeing _an_order_of_magnitude_ more taper than that. 3/64" over
seven feet is WAY TOO MUCH.

Understood but maybe you missed the subtitle indicator that he gave,

" the work piece gets progressively narrower or thinner - I've been getting
1/32" -
3/64" per 7'. After most of a weekend working on this I am
baffled.

If you run a piece through the jointer enough times it is going to add up
and especially if you are a beginner on a board that is not straight.
"The" work piece gets progressively narrower or thinner over most of the
weekend. I read that as he has been going over and over and over on the
same board.

In article , "Leon" wrote:

"Doug Miller" wrote in message
...
In article , "Leon"


You're missing the point, Leon. The unavoidable slight taper you're
talking
about is on the order of a few thousandths of an inch over three or four
feet,
if the jointer is set up properly and the operator's technique is good.

The OP is seeing _an_order_of_magnitude_ more taper than that. 3/64" over
seven feet is WAY TOO MUCH.

Understood but maybe you missed the subtitle indicator that he gave,

" the work piece gets progressively narrower or thinner - I've been getting
1/32" -
3/64" per 7'. After most of a weekend working on this I am
baffled.

If you run a piece through the jointer enough times it is going to add up
and especially if you are a beginner on a board that is not straight.
"The" work piece gets progressively narrower or thinner over most of the
weekend. I read that as he has been going over and over and over on the
same board.

And I took it to mean that he's seeing that much taper on a _single_pass_ and
has been trying all weekend to correct the problem - *not* that he's been
running the *same* board through the jointer all weekend.

Perhaps the OP can clarify.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?

"Doug Miller" wrote in message
. ..

And I took it to mean that he's seeing that much taper on a _single_pass_
and
has been trying all weekend to correct the problem - *not* that he's been
running the *same* board through the jointer all weekend.

Perhaps the OP can clarify.


Yeah, I think some pertinent details may have been left out.