***The below is referring to the 5-cut method of squaring a table saw sled fence to 90 degrees.

Unless I am mistaken, it is a misconception to think that the 5-cut method squares your table saw blade to the sled fence. What it really does is square your fence to 90 degrees of the direction of travel (miter track). If the blade was angled by a small amount the process would still align the fence 90 degrees to the direction of sled travel.

If the table saw blade were a cutting laser projecting 90 degrees to the table, the 5-cut method would still work. Because this is true, the thought that the 5-cut method squares your fence 90 degrees to a blade can not be true.

Am I missing something? I know it's picky but it makes me cringe when people make that claim.

On 10/2/2013 8:25 AM, wrote:
***The below is referring to the 5-cut method of squaring a table saw sled fence to 90 degrees.

Unless I am mistaken, it is a misconception to think that the 5-cut method squares your table saw blade to the sled fence.

What it really does is square your fence to 90 degrees of the direction
of travel (miter track). If the blade

was angled by a small amount the process would still align the fence
90 degrees to the direction of sled travel.

If the table saw blade were a cutting laser projecting 90 degrees to the table, the 5-cut method would still work.

Because this is true, the thought that the 5-cut method squares your
fence 90 degrees to a blade can not be true.

Am I missing something? I know it's picky but it makes me cringe when people make that claim.


I have always questioned the 5-cut process. If the blade were not
parallel to the fence. the blade would cut a wider kerf.

Once the angle between the blade and fence became large enough I suspect
there would be problem.

Has any body tried to measure the parallelism by measuring the width of
the teeth on the blade, to the width of the kerf?

On Wednesday, October 2, 2013 8:35:37 AM UTC-4, wrote:
On 10/2/2013 8:25 AM, wrote:

***The below is referring to the 5-cut method of squaring a table saw sled fence to 90 degrees.



Unless I am mistaken, it is a misconception to think that the 5-cut method squares your table saw blade to the sled fence.



What it really does is square your fence to 90 degrees of the direction

of travel (miter track). If the blade



was angled by a small amount the process would still align the fence

90 degrees to the direction of sled travel.



If the table saw blade were a cutting laser projecting 90 degrees to the table, the 5-cut method would still work.



Because this is true, the thought that the 5-cut method squares your

fence 90 degrees to a blade can not be true.



Am I missing something? I know it's picky but it makes me cringe when people make that claim.





I have always questioned the 5-cut process. If the blade were not

parallel to the fence.


I assume you mean perpendicular and not parallel.

the blade would cut a wider kerf.

Exactly. Analogous to a fatter or skinnier cutting laser. The process does NOT consider the squareness of the blade to the sled fence. Only that the process involves cutting.






Once the angle between the blade and fence became large enough I suspect

there would be problem.



Has any body tried to measure the parallelism by measuring the width of

the teeth on the blade, to the width of the kerf?

** Should have read:

It only matters that the process involves cutting.

On 10/2/2013 9:10 AM, wrote:
I have always questioned the 5-cut process. If the blade were not

parallel to the fence.

I assume you mean perpendicular and not parallel.


Basic geometry:

Parallel lines never meet. ||

Perpendicular lines met at a 90 degree angle _|

On 10/2/2013 7:35 AM, Keith Nuttle wrote:
....

Has any body tried to measure the parallelism by measuring the width of
the teeth on the blade, to the width of the kerf?

That would also add any runout in the blade/spindle to the indication of
misalignment.

--

On 10/2/2013 7:25 AM, wrote:
***The below is referring to the 5-cut method of squaring a table saw sled fence to 90 degrees.

Unless I am mistaken, it is a misconception to think that the 5-cut method squares your table saw blade to the sled fence. What it really does is square your fence to 90 degrees of the direction of travel (miter track). If the blade was angled by a small amount the process would still align the fence 90 degrees to the direction of sled travel.

If the table saw blade were a cutting laser projecting 90 degrees to the table, the 5-cut method would still work. Because this is true, the thought that the 5-cut method squares your fence 90 degrees to a blade can not be true.

Am I missing something? I know it's picky but it makes me cringe when people make that claim.



Your thoughts are mostly correct. With the assumption that the saw is
set up precisely to begin with, the 5 cut works for squaring the miter
fence to the blade "ONLY" if the blade is parallel to the miter guide
slot to begin with. It does this by squaring the miter fence to the
direction of travel, therefore the blade is square to the miter fence also.

If you blade is parallel to the miter slot to start with it works, if
not it does not.

For most people, words are simply a way of *relating* to ideas, not
*defining* them. As long as the right idea is communicated,
communication has happened successfully.

Perhaps they mean "[...] the cut made by your blade by moving the sled
along the miter slot" but abbreviate it to "[...] the blade" because
everyone's blade is true enough that it doesn't matter?

Also, to true the blade to the cut it makes, I cross-cut some hardwood
and inspect the teeth marks in the wood, to make sure I have as deep
marks from both "front teeth cutting down" and "back teeth cutting up".
Just an FYI aside :-)

On Wednesday, October 2, 2013 11:31:30 AM UTC-4, DJ Delorie wrote:
For most people, words are simply a way of *relating* to ideas, not

*defining* them. As long as the right idea is communicated,

communication has happened successfully.



Perhaps they mean "[...] the cut made by your blade by moving the sled

along the miter slot" but abbreviate it to "[...] the blade" because

everyone's blade is true enough that it doesn't matter?


I only wish that were true. There is a common misconception that is quite wide spread (in my encounters w/ folks discussing alignment) that the 5-cut method aligns the fence with the blade to 90 degrees.

A common criticism that I receive from folks when I discuss using a dial indicator and a square to align a sled fence to 90 (see link below for an example in the comments) is that the 5-cut method is superior BECAUSE it aligns the fence to the blade while the dial indicator only aligns the fence to the miter track. While their logic is flawed as discussed in my original post, it is also flawed in other ways as well. Assuming they are correct, they would still need to have a blade aligned with the miter track regardless.


See he
http://www.youtube.com/watch?v=YTlpY_chcio

Alignment method is at 5:30. See first comment.







Also, to true the blade to the cut it makes, I cross-cut some hardwood

and inspect the teeth marks in the wood, to make sure I have as deep

marks from both "front teeth cutting down" and "back teeth cutting up".

Just an FYI aside :-)

Am I missing something? I know it's picky but it makes me cringe when people make that claim.

You are correct but even if the blade is out of square a bit or perfectly square at some position but has runout so it is not square at other positions, it just cuts a wider kerf but results in a square cut so you end up in the same place.

I think typically people would first align the top to the blade (you usually move the top, not the blade\trunnion) using some prescribed method (usually a dial indicator). Then the 5 cut can give you a quick way to line up fences\accesories.

On 10/2/2013 9:10 AM, Leon wrote:
On 10/2/2013 7:25 AM, wrote:
***The below is referring to the 5-cut method of squaring a table saw
sled fence to 90 degrees.

Unless I am mistaken, it is a misconception to think that the 5-cut
method squares your table saw blade to the sled fence. What it really
does is square your fence to 90 degrees of the direction of travel
(miter track). If the blade was angled by a small amount the process
would still align the fence 90 degrees to the direction of sled travel.

If the table saw blade were a cutting laser projecting 90 degrees to
the table, the 5-cut method would still work. Because this is true,
the thought that the 5-cut method squares your fence 90 degrees to a
blade can not be true.

Am I missing something? I know it's picky but it makes me cringe when
people make that claim.



Your thoughts are mostly correct. With the assumption that the saw is
set up precisely to begin with, the 5 cut works for squaring the miter
fence to the blade "ONLY" if the blade is parallel to the miter guide
slot to begin with. It does this by squaring the miter fence to the
direction of travel, therefore the blade is square to the miter fence also.

If you blade is parallel to the miter slot to start with it works, if
not it does not.

You are supposed to square the blade to the miter slot first.

On 10/2/2013 1:02 PM, Just Wondering wrote:
On 10/2/2013 9:10 AM, Leon wrote:
On 10/2/2013 7:25 AM, wrote:
***The below is referring to the 5-cut method of squaring a table saw
sled fence to 90 degrees.

Unless I am mistaken, it is a misconception to think that the 5-cut
method squares your table saw blade to the sled fence. What it really
does is square your fence to 90 degrees of the direction of travel
(miter track). If the blade was angled by a small amount the process
would still align the fence 90 degrees to the direction of sled travel.

If the table saw blade were a cutting laser projecting 90 degrees to
the table, the 5-cut method would still work. Because this is true,
the thought that the 5-cut method squares your fence 90 degrees to a
blade can not be true.

Am I missing something? I know it's picky but it makes me cringe when
people make that claim.



Your thoughts are mostly correct. With the assumption that the saw is
set up precisely to begin with, the 5 cut works for squaring the miter
fence to the blade "ONLY" if the blade is parallel to the miter guide
slot to begin with. It does this by squaring the miter fence to the
direction of travel, therefore the blade is square to the miter fence
also.

If you blade is parallel to the miter slot to start with it works, if
not it does not.

You are supposed to square the blade to the miter slot first.

Yes you are but some don't realize this.

On 10/2/2013 10:31 AM, DJ Delorie wrote:

For most people, words are simply a way of *relating* to ideas, not
*defining* them. As long as the right idea is communicated,
communication has happened successfully.

Perhaps they mean "[...] the cut made by your blade by moving the sled
along the miter slot" but abbreviate it to "[...] the blade" because
everyone's blade is true enough that it doesn't matter?

Also, to true the blade to the cut it makes, I cross-cut some hardwood
and inspect the teeth marks in the wood, to make sure I have as deep
marks from both "front teeth cutting down" and "back teeth cutting up".
Just an FYI aside :-)



If you see tooth marks on the front and back of the cut you need a
better blade. Tooth marks on a crosscut is something I DO NOT tolerate
I barely tolerate them on a rip. ;~)

On 10/2/2013 10:41 AM, wrote:
On Wednesday, October 2, 2013 11:31:30 AM UTC-4, DJ Delorie wrote:
For most people, words are simply a way of *relating* to ideas, not

*defining* them. As long as the right idea is communicated,

communication has happened successfully.



Perhaps they mean "[...] the cut made by your blade by moving the sled

along the miter slot" but abbreviate it to "[...] the blade" because

everyone's blade is true enough that it doesn't matter?


I only wish that were true. There is a common misconception that is quite wide spread (in my encounters w/ folks discussing alignment) that the 5-cut method aligns the fence with the blade to 90 degrees.

A common criticism that I receive from folks when I discuss using a dial indicator and a square to align a sled fence to 90 (see link below for an example in the comments) is that the 5-cut method is superior BECAUSE it aligns the fence to the blade while the dial indicator only aligns the fence to the miter track. While their logic is flawed as discussed in my original post, it is also flawed in other ways as well. Assuming they are correct, they would still need to have a blade aligned with the miter track regardless.


See he
http://www.youtube.com/watch?v=YTlpY_chcio

Alignment method is at 5:30. See first comment.


I see two things that can introduce error.

1. If you square is not square.

2. And what ever threw your fence out between squaring it and locking
it in place.

Food for thought for your next sled, In-Line Industries makes a cross
cut sled called the Dubby. I have been using both a left and right hand
for 14+ years with great results.

FWIW Rockler has attempted to copy the design but falls short.

I think if one was spartan enough he could duplicate the Dubby and save
a couple hundred dollars.

The Dubby sled fence adjusts a lot like your fence did for squaring
purposes. The Dubby fences adjusts so that you can have an infinite
number of miter angles. The Dubby also has a fixed back stop with an
adjustment screw to square and insure the fence returns square after
cutting an angle.

Additionally the Dubby sled is extremely accurate at setting angles, it
has a stainless steel angle gauge that runs along the edge of the sled
to align with the front of the fence. The fence moves an average of
1/4" between each degree marker so setting the fence to a specific
degree mark is going to get you dead close to perfect with out effort.

Leon lcb11211@swbelldotnet writes:
If you see tooth marks on the front and back of the cut you need a
better blade.

Normally true, except I use a magnifier to see them. Which just makes
them more accurate as a means of squaring ;-)

I suppose you could keep a cheap blade around just to square the blade
to the table! :-)

On 10/2/2013 3:21 PM, Leon wrote:
On 10/2/2013 10:41 AM, wrote:
On Wednesday, October 2, 2013 11:31:30 AM UTC-4, DJ Delorie wrote:
For most people, words are simply a way of *relating* to ideas, not

*defining* them. As long as the right idea is communicated,

communication has happened successfully.



Perhaps they mean "[...] the cut made by your blade by moving the sled

along the miter slot" but abbreviate it to "[...] the blade" because

everyone's blade is true enough that it doesn't matter?


I only wish that were true. There is a common misconception that is
quite wide spread (in my encounters w/ folks discussing alignment)
that the 5-cut method aligns the fence with the blade to 90 degrees.

A common criticism that I receive from folks when I discuss using a
dial indicator and a square to align a sled fence to 90 (see link
below for an example in the comments) is that the 5-cut method is
superior BECAUSE it aligns the fence to the blade while the dial
indicator only aligns the fence to the miter track. While their logic
is flawed as discussed in my original post, it is also flawed in other
ways as well. Assuming they are correct, they would still need to
have a blade aligned with the miter track regardless.


See he
http://www.youtube.com/watch?v=YTlpY_chcio

Alignment method is at 5:30. See first comment.


I see two things that can introduce error.

1. If you square is not square.

2. And what ever threw your fence out between squaring it and locking
it in place.

Food for thought for your next sled, In-Line Industries makes a cross
cut sled called the Dubby. I have been using both a left and right hand
for 14+ years with great results.

FWIW Rockler has attempted to copy the design but falls short.

I think if one was spartan enough he could duplicate the Dubby and save
a couple hundred dollars.

The Dubby sled fence adjusts a lot like your fence did for squaring
purposes. The Dubby fences adjusts so that you can have an infinite
number of miter angles. The Dubby also has a fixed back stop with an
adjustment screw to square and insure the fence returns square after
cutting an angle.

Additionally the Dubby sled is extremely accurate at setting angles, it
has a stainless steel angle gauge that runs along the edge of the sled
to align with the front of the fence. The fence moves an average of
1/4" between each degree marker so setting the fence to a specific
degree mark is going to get you dead close to perfect with out effort.




And you forgot to mention that the stainless angle gauge can be reset
to zero it out after making a dead on square cut and getting the stop set.

--
Jeff

On 10/2/2013 5:29 PM, Edward A. Falk wrote:
In article ,
wrote:
***The below is referring to the 5-cut method of squaring a table saw sled fence to 90 degrees.

Unless I am mistaken, it is a misconception to think that the 5-cut method squares your table saw
blade to the sled fence. What it really does is square your fence to 90 degrees of the direction of
travel (miter track). If the blade was angled by a small amount the process would still align the
fence 90 degrees to the direction of sled travel.

If the table saw blade were a cutting laser projecting 90 degrees to the table, the 5-cut method
would still work. Because this is true, the thought that the 5-cut method squares your fence 90
degrees to a blade can not be true.

Am I missing something? I know it's picky but it makes me cringe when people make that claim.


The best you can hope for on a table saw is to use the slots in the
table as your "master". That's because those are the one thing
you can't adjust.


Actually with cabinet saws, you do adjust the location of the slots.

Everything else must either be parallel to the slots (blade, fence),
or square to the slots (cross-cut sled).

If your blade is not parallel to the fence, the cuts you make on it
will still be true, but the kerf will be wider, and narrower on the
top than at the bottom, which is a bad thing, but for small errors,
usually unnoticable.


Up to a point, if the back of the blade is enough further away than the
front, from the fence. the work will taper as you feed it. the blade
will pull the work away from the fence.

On 10/2/2013 4:51 PM, DJ Delorie wrote:

Leon lcb11211@swbelldotnet writes:
If you see tooth marks on the front and back of the cut you need a
better blade.

Normally true, except I use a magnifier to see them. Which just makes
them more accurate as a means of squaring ;-)

I doubt you would see tooth marks with a magnifier, except perhaps a
microscope, with the cuts I am getting when cross cutting. ;~)


I suppose you could keep a cheap blade around just to square the blade
to the table! :-)

On Wed, 02 Oct 2013 22:16:39 -0500, Leon lcb11211@swbelldotnet
wrote:

On 10/2/2013 5:29 PM, Edward A. Falk wrote:
In article ,
wrote:
***The below is referring to the 5-cut method of squaring a table saw sled fence to 90 degrees.

Unless I am mistaken, it is a misconception to think that the 5-cut method squares your table saw
blade to the sled fence. What it really does is square your fence to 90 degrees of the direction of
travel (miter track). If the blade was angled by a small amount the process would still align the
fence 90 degrees to the direction of sled travel.

If the table saw blade were a cutting laser projecting 90 degrees to the table, the 5-cut method
would still work. Because this is true, the thought that the 5-cut method squares your fence 90
degrees to a blade can not be true.

Am I missing something? I know it's picky but it makes me cringe when people make that claim.


The best you can hope for on a table saw is to use the slots in the
table as your "master". That's because those are the one thing
you can't adjust.


Actually with cabinet saws, you do adjust the location of the slots.

Yep. The blade is fixed and you align the top to it.

Everything else must either be parallel to the slots (blade, fence),
or square to the slots (cross-cut sled).

If your blade is not parallel to the fence, the cuts you make on it
will still be true, but the kerf will be wider, and narrower on the
top than at the bottom, which is a bad thing, but for small errors,
usually unnoticable.


Up to a point, if the back of the blade is enough further away than the
front, from the fence. the work will taper as you feed it. the blade
will pull the work away from the fence.

Or pinches the wood between the fence and the blade, bending the blade
and burning the wood.