How do I square the blade? My blade runs out by 2mm .

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On 30/03/2021 16:01, Collie1956 wrote:

How do I square the blade? My blade runs out by 2mm .

There are three different "squares" you can check. The vertical square -
i.e. is the tilt 90 degrees to the table surface in the full upright
position. Most saws have adjustment screws on the limits of the tilt
mechanism to set this.

Next thing is to get it parallel to the slots on the table surface. Many
saws will allow the bolts retaining the table to be slackened and the
angle of the table shifted slightly. To check this place a bit of wood
in the slot and slide something about the right width up to it, and
align the blade so it looks parallel to the wood. Then use a dial test
indicator so that you can run it along the blade against something in
the slot. Again tapping the table gently until they are properly parallel.

Last thing it to align the fence. There are usually adjustment screws
for this - you can line that up with a table slot to start with, and do
a final check against the blade. (if you did the previous step right,
then the blade and the slot should be parallel anyway).



--
Cheers,

John.

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On 30/03/2021 16:09, John Rumm wrote:
On 30/03/2021 16:01, Collie1956 wrote:

How do I square the blade? My blade runs out by 2mm .

There are three different "squares" you can check. The vertical square -
i.e. is the tilt 90 degrees to the table surface in the full upright
position. Most saws have adjustment screws on the limits of the tilt
mechanism to set this.

Next thing is to get it parallel to the slots on the table surface. Many
saws will allow the bolts retaining the table to be slackened and the
angle of the table shifted slightly. To check this place a bit of wood
in the slot and slide something about the right width up to it, and
align the blade so it looks parallel to the wood. Then use a dial test
indicator so that you can run it along the blade against something in
the slot. Again tapping the table gently until they are properly parallel.

Last thing it to align the fence. There are usually adjustment screws
for this - you can line that up with a table slot to start with, and do
a final check against the blade. (if you did the previous step right,
then the blade and the slot should be parallel anyway).



I guess the other possible fault that could need "squaring" is swash in
the blade, caused by poor seating in the washers or distortion of the
blade itself.

On 30/03/2021 16:21, newshound wrote:
On 30/03/2021 16:09, John Rumm wrote:
On 30/03/2021 16:01, Collie1956 wrote:

How do I square the blade? My blade runs out by 2mm .

There are three different "squares" you can check. The vertical square
- i.e. is the tilt 90 degrees to the table surface in the full upright
position. Most saws have adjustment screws on the limits of the tilt
mechanism to set this.

Next thing is to get it parallel to the slots on the table surface.
Many saws will allow the bolts retaining the table to be slackened and
the angle of the table shifted slightly. To check this place a bit of
wood in the slot and slide something about the right width up to it,
and align the blade so it looks parallel to the wood. Then use a dial
test indicator so that you can run it along the blade against
something in the slot. Again tapping the table gently until they are
properly parallel.

Last thing it to align the fence. There are usually adjustment screws
for this - you can line that up with a table slot to start with, and
do a final check against the blade. (if you did the previous step
right, then the blade and the slot should be parallel anyway).



I guess the other possible fault that could need "squaring" is swash in
the blade, caused by poor seating in the washers or distortion of the
blade itself.

True, but that is not something that you can typically "tune out" so
easily.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 30/03/2021 16:01, Collie1956 wrote:
How do I square the blade? My blade runs out by 2mm .


It took me a while to visualise it, but if the fence isn't parallel to
the blade you still get a parallel cut - just one with a wider kerf.

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Reentrant

On 31/03/2021 17:03, Reentrant wrote:
On 30/03/2021 16:01, Collie1956 wrote:
How do I square the blade? My blade runs out by 2mm .


It took me a while to visualise it, but if the fence isn't parallel to
the blade you still get a parallel cut - just one with a wider kerf.

Its also potentially very dangerous - since if the fence is closer to
the back of the blade than the front, it will cause the wood to pinch at
the back where the blade is rising from the table. That has the habit of
grabbing the wood and throwing it up and at you! The other way round is
slightly less dangerous, but still best avoided for a number of reasons.




--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 31/03/2021 17:10, John Rumm wrote:
On 31/03/2021 17:03, Reentrant wrote:
On 30/03/2021 16:01, Collie1956 wrote:
How do I square the blade? My blade runs out by 2mm .


It took me a while to visualise it, but if the fence isn't parallel to
the blade you still get a parallel cut - just one with a wider kerf.

Its also potentially very dangerous - since if the fence is closer to
the back of the blade than the front, it will cause the wood to pinch at
the back where the blade is rising from the table. That has the habit of
grabbing the wood and throwing it up and at you! The other way round is
slightly less dangerous, but still best avoided for a number of reasons.

Don't ask me where I got it from but I am certain that I read in a
manual or text book once to set the fence so the blade was just ever so
slightly toe-in. eg the front of the blade closer to the fence than the
rear.

TW

On 02/04/2021 10:27, TimW wrote:
On 31/03/2021 17:10, John Rumm wrote:
On 31/03/2021 17:03, Reentrant wrote:
On 30/03/2021 16:01, Collie1956 wrote:
How do I square the blade? My blade runs out by 2mm .


It took me a while to visualise it, but if the fence isn't parallel
to the blade you still get a parallel cut - just one with a wider kerf.

Its also potentially very dangerous - since if the fence is closer to
the back of the blade than the front, it will cause the wood to pinch
at the back where the blade is rising from the table. That has the
habit of grabbing the wood and throwing it up and at you! The other
way round is slightly less dangerous, but still best avoided for a
number of reasons.

Don't ask me where I got it from but I am certain that I read in a
manual or text book once to set the fence so the blade was just ever so
slightly toe-in. eg the front of the blade closer to the fence than the
rear.

TW

I've seen that too, I always assumed it was to help to keep you just
clear of the more dangerous case.

On 02/04/2021 10:27, TimW wrote:
On 31/03/2021 17:10, John Rumm wrote:
On 31/03/2021 17:03, Reentrant wrote:
On 30/03/2021 16:01, Collie1956 wrote:
How do I square the blade? My blade runs out by 2mm .


It took me a while to visualise it, but if the fence isn't parallel
to the blade you still get a parallel cut - just one with a wider kerf.

Its also potentially very dangerous - since if the fence is closer to
the back of the blade than the front, it will cause the wood to pinch
at the back where the blade is rising from the table. That has the
habit of grabbing the wood and throwing it up and at you! The other
way round is slightly less dangerous, but still best avoided for a
number of reasons.

Don't ask me where I got it from but I am certain that I read in a
manual or text book once to set the fence so the blade was just ever so
slightly toe-in. eg the front of the blade closer to the fence than the
rear.

Best you can say of that is if you are going to have an error in
alignment, then that is the safer direction to have it.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Fri, 2 Apr 2021 18:39:09 +0100, John Rumm
wrote:

Best you can say of that is if you are going to have an error in
alignment, then that is the safer direction to have it.

Eh... depends?

I know of a table saw, large, cross slide over a meter, and the cross slide and
fence were not a 90° to each other, but very slightly off. It bothered me, but
the machine was new, and rather than fool with it myself, I asked when it was
first serviced by the manufacturer:

This saw was (also) used for melamine-faced chipboard, generally using
many-toothed carbide blades with specialized tooth shapes.

It is set assuming that the "good" piece from a cut was either between the fence
and the blade, or against the cross slide. Cutting against the fence, the saw
blade enters into the material from the top, leaving an unchipped edge on the
top. At the back end of the kerf, where the blade comes up, there is a bit of
clearance. This keeps the edge unchipped. The clearance was below 1/10th of a
millimeter. Cutting with the material held against the cross slide, the
clearance was on the other side, i.e. the piece on the fence side got the teeth
where they came "up", with more noticeable chipping.

(Some of these table saws have a pre-cutter to avoid tearing on the underside of
the chipboard, but this machine was also used for solid wood, where the
pre-cutter is in the way...)

The machine was a similar model to this one:

https://www.felder-group.com/en-gb/products/5-function-combination-machines-c1952/combination-machine-cf-741-p142858

Cutting with material against both the slide and the fence is a no-no, for one
because the two are not at 90° to each other. (Also because there is no place
for the wood to fall away freely, and scrap can get caught between fence and
blade, and shoot out the back...)



Thomas Prufer