I think about improving DE from time to time (whenever I'm cleaning-up
after a messy job) but don't seem to find the necessary tuit. My saw has
a small hose from the crown guard (hinged on the riving knife) that goes
inside and joins the under-saw 50mm hose to come out to a 100mm port
that I connect to my 2HP HVLP cyclone extractor. I frequently operate
without the crown guard(!!) so plug the crown guard hose.
I'd like to devise a pivoting and self-adjusting crown guard that's
suspended from a hollow tube that's attached to the saw in some way and
can be used for DE. The crown extraction would be connected to the
under-saw hose with a throttle'able Y connection and then go to the LVHP
extractor.
Issues: how to make the suspension rigid enough (but allow the saw to be
moved), how to improve collection beneath the saw, ...
Suggestions and comments invited.

wrote:

I think about improving DE from time to time

check mike farrington on youtube, ISTR he built a table saw dust
extraction system ...

On Thursday, 15 April 2021 at 09:37:10 UTC+1, Andy Burns wrote:
wrote:

I think about improving DE from time to time
check mike farrington on youtube, ISTR he built a table saw dust
extraction system ...
For dust extraction to be fully effective it needs to be extracted at the point it is produced. On a table saw that is the point at the front of the blade as it passes under the table. On industrial scale saws you will find nozzles directed as close as possible to that point under the table. What is not captured at that point and spins round with the blade is usually sucked up by the outlet at the back of the saw.

Richard

On 15/04/2021 10:12, Tricky Dicky wrote:
On Thursday, 15 April 2021 at 09:37:10 UTC+1, Andy Burns wrote:
wrote:

I think about improving DE from time to time
check mike farrington on youtube, ISTR he built a table saw dust
extraction system ...
For dust extraction to be fully effective it needs to be extracted at the point it is produced. On a table saw that is the point at the front of the blade as it passes under the table. On industrial scale saws you will find nozzles directed as close as possible to that point under the table. What is not captured at that point and spins round with the blade is usually sucked up by the outlet at the back of the saw.

Richard

That makes sense, but I'm still using the manufacturer's under-sawblade
collection casing because I haven't (yet) managed to devise a better way
to collect the dust at the front and not get in the way of the tilting
arbour.

On 15/04/2021 09:37, Andy Burns wrote:
wrote:

I think about improving DE from time to time

check mike farrington on youtube, ISTR he built a table saw dust
extraction system ...


Thanks, he's got some good videos (and an envy-makingly HUGE workshop)

On 15/04/2021 09:08, wrote:

I think about improving DE from time to time (whenever I'm cleaning-up
after a messy job) but don't seem to find the necessary tuit. My saw has
a small hose from the crown guard (hinged on the riving knife) that goes
inside and joins the under-saw 50mm hose to come out to a 100mm port
that I connect to my 2HP HVLP cyclone extractor. I frequently operate
without the crown guard(!!) so plug the crown guard hose.

One of the problems you might find with the smaller hose up top is that
its not as well suited to the HVLP extractor because of its higher back
pressure. Some people find running a separate LVHP collector (e.g a shop
vac style collector) just for the top hose works better.

I'd like to devise a pivoting and self-adjusting crown guard that's
suspended from a hollow tube that's attached to the saw in some way and
can be used for DE. The crown extraction would be connected to the
under-saw hose with a throttle'able Y connection and then go to the LVHP
extractor.
Issues: how to make the suspension rigid enough (but allow the saw to be
moved), how to improve collection beneath the saw, ...
Suggestions and comments invited.

There are quite a few examples of this kind of thing about - most are
quite large since they need to reach over the saw from far enough away
as to not curtail the maximum size of sheet you can process.

https://wayofwood.com/diy-tablesaw-o...d-blade-guard/

or

https://www.axminstertools.com/axmin...e-guard-104504

You may find that building a cowl to mount under the table to enclose as
much of the blade as you can (either fixed to the trunnions so that it
an tilt, or just wide enough that it can accommodate the tilt, and
connecting that to the HVLP collector will increase the air speed under
the blade high enough that it can capture everything flying off the tips
of the blade, before it gets a chance to escape again.

My saw was basically designed to just dump dust into its base for later
manual removal. However I added a 4" port to it. Running that into the
HVLP does reduce the amount that gets out of the case - but not
completely. (not helped by other piercings through the case like by the
blade height adjust wheel that let air be sucked in via alternate routes).

I found just adding a bit of tube split round the blade where it exits
the underside of the table, was quite effective on this contraption:

http://wiki.diyfaq.org.uk/index.php/...awbench#In_Use

That might not be too difficult to mount such that it moves in sympathy
with the blade tilt.


--
Cheers,

John.

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

On 15/04/2021 14:03, John Rumm wrote:
On 15/04/2021 09:08, wrote:

I think about improving DE from time to time (whenever I'm cleaning-up
after a messy job) but don't seem to find the necessary tuit. My saw
has a small hose from the crown guard (hinged on the riving knife)
that goes inside and joins the under-saw 50mm hose to come out to a
100mm port that I connect to my 2HP HVLP cyclone extractor. I
frequently operate without the crown guard(!!) so plug the crown guard
hose.

One of the problems you might find with the smaller hose up top is that
its not as well suited to the HVLP extractor because of its higher back
pressure. Some people find running a separate LVHP collector (e.g a shop
vac style collector) just for the top hose works better.
Yes, a little experimentation makes it seem that LVHP is better for both
top and bottom with the current internal plumbing.

I'd like to devise a pivoting and self-adjusting crown guard that's
suspended from a hollow tube that's attached to the saw in some way
and can be used for DE. The crown extraction would be connected to the
under-saw hose with a throttle'able Y connection and then go to the
LVHP extractor.
Issues: how to make the suspension rigid enough (but allow the saw to
be moved), how to improve collection beneath the saw, ...
Suggestions and comments invited.

There are quite a few examples of this kind of thing about - most are
quite large since they need to reach over the saw from far enough away
as to not curtail the maximum size of sheet you can process.

https://wayofwood.com/diy-tablesaw-o...d-blade-guard/

or

https://www.axminstertools.com/axmin...e-guard-104504
Thanks for those - thought-provoking and similar to what I had in mind
(but I can't believe Axminster sell many at that price)


You may find that building a cowl to mount under the table to enclose as
much of the blade as you can (either fixed to the trunnions so that it
an tilt, or just wide enough that it can accommodate the tilt, and
connecting that to the HVLP collector will increase the air speed under
the blade high enough that it can capture everything flying off the tips
of the blade, before it gets a chance to escape again.

My saw was basically designed to just dump dust into its base for later
manual removal. However I added a 4" port to it. Running that into the
HVLP does reduce the amount that gets out of the case - but not
completely. (not helped by other piercings through the case like by the
blade height adjust wheel that let air be sucked in via alternate routes).

I found just adding a bit of tube split round the blade where it exits
the underside of the table, was quite effective on this contraption:

http://wiki.diyfaq.org.uk/index.php/...awbench#In_Use

That might not be too difficult to mount such that it moves in sympathy
with the blade tilt.


I'm moving towards using a good LVHP almost everywhere (with cyclone,
50mm plastic ducting and home-made blast gates) and only using the HVLP
for the planer thicknesser, and maybe the (rarely used) wood lathe. I
suppose, if I ever get around to inventing something, a dust catcher for
the chop saw might be HVLP as well.

On 16/04/2021 11:11, wrote:
On 15/04/2021 14:03, John Rumm wrote:
On 15/04/2021 09:08, wrote:

I think about improving DE from time to time (whenever I'm
cleaning-up after a messy job) but don't seem to find the necessary
tuit. My saw has a small hose from the crown guard (hinged on the
riving knife) that goes inside and joins the under-saw 50mm hose to
come out to a 100mm port that I connect to my 2HP HVLP cyclone
extractor. I frequently operate without the crown guard(!!) so plug
the crown guard hose.

One of the problems you might find with the smaller hose up top is
that its not as well suited to the HVLP extractor because of its
higher back pressure. Some people find running a separate LVHP
collector (e.g a shop vac style collector) just for the top hose works
better.
Yes, a little experimentation makes it seem that LVHP is better for both
top and bottom with the current internal plumbing.

I'd like to devise a pivoting and self-adjusting crown guard that's
suspended from a hollow tube that's attached to the saw in some way
and can be used for DE. The crown extraction would be connected to
the under-saw hose with a throttle'able Y connection and then go to
the LVHP extractor.
Issues: how to make the suspension rigid enough (but allow the saw to
be moved), how to improve collection beneath the saw, ...
Suggestions and comments invited.

There are quite a few examples of this kind of thing about - most are
quite large since they need to reach over the saw from far enough away
as to not curtail the maximum size of sheet you can process.

https://wayofwood.com/diy-tablesaw-o...d-blade-guard/

or

https://www.axminstertools.com/axmin...e-guard-104504

Thanks for those - thought-provoking and similar to what I had in mind
(but I can't believe Axminster sell many at that price)

Probably not - and there are probably cheaper alternatives about. It was
more just an example. Some of the saw makers do their own ones as well.



You may find that building a cowl to mount under the table to enclose
as much of the blade as you can (either fixed to the trunnions so that
it an tilt, or just wide enough that it can accommodate the tilt, and
connecting that to the HVLP collector will increase the air speed
under the blade high enough that it can capture everything flying off
the tips of the blade, before it gets a chance to escape again.

My saw was basically designed to just dump dust into its base for
later manual removal. However I added a 4" port to it. Running that
into the HVLP does reduce the amount that gets out of the case - but
not completely. (not helped by other piercings through the case like
by the blade height adjust wheel that let air be sucked in via
alternate routes).

I found just adding a bit of tube split round the blade where it exits
the underside of the table, was quite effective on this contraption:

http://wiki.diyfaq.org.uk/index.php/...awbench#In_Use

That might not be too difficult to mount such that it moves in
sympathy with the blade tilt.


I'm moving towards using a good LVHP almost everywhere (with cyclone,
50mm plastic ducting and home-made blast gates) and only using the HVLP
for the planer thicknesser, and maybe the (rarely used) wood lathe. I
suppose, if I ever get around to inventing something, a dust catcher for
the chop saw might be HVLP as well.

IME HVLP shines for really high volume dust or chip creation (so
planners / thicknessers), and anything where its difficult to catch the
dust in something first and need to rely on really high speed airflow to
capture stuff being ejected from a blade tip.

--
Cheers,

John.

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

On 17/04/2021 01:11, John Rumm wrote:
On 16/04/2021 11:11, wrote:
On 15/04/2021 14:03, John Rumm wrote:
On 15/04/2021 09:08, wrote:

I think about improving DE from time to time (whenever I'm
cleaning-up after a messy job) but don't seem to find the necessary
tuit. My saw has a small hose from the crown guard (hinged on the
riving knife) that goes inside and joins the under-saw 50mm hose to
come out to a 100mm port that I connect to my 2HP HVLP cyclone
extractor. I frequently operate without the crown guard(!!) so plug
the crown guard hose.

One of the problems you might find with the smaller hose up top is
that its not as well suited to the HVLP extractor because of its
higher back pressure. Some people find running a separate LVHP
collector (e.g a shop vac style collector) just for the top hose
works better.
Yes, a little experimentation makes it seem that LVHP is better for
both top and bottom with the current internal plumbing.

I'd like to devise a pivoting and self-adjusting crown guard that's
suspended from a hollow tube that's attached to the saw in some way
and can be used for DE. The crown extraction would be connected to
the under-saw hose with a throttle'able Y connection and then go to
the LVHP extractor.
Issues: how to make the suspension rigid enough (but allow the saw
to be moved), how to improve collection beneath the saw, ...
Suggestions and comments invited.

There are quite a few examples of this kind of thing about - most are
quite large since they need to reach over the saw from far enough
away as to not curtail the maximum size of sheet you can process.

https://wayofwood.com/diy-tablesaw-o...d-blade-guard/

or

https://www.axminstertools.com/axmin...e-guard-104504


Thanks for those - thought-provoking and similar to what I had in mind
(but I can't believe Axminster sell many at that price)

Probably not - and there are probably cheaper alternatives about. It was
more just an example. Some of the saw makers do their own ones as well.



You may find that building a cowl to mount under the table to enclose
as much of the blade as you can (either fixed to the trunnions so
that it an tilt, or just wide enough that it can accommodate the
tilt, and connecting that to the HVLP collector will increase the air
speed under the blade high enough that it can capture everything
flying off the tips of the blade, before it gets a chance to escape
again.

My saw was basically designed to just dump dust into its base for
later manual removal. However I added a 4" port to it. Running that
into the HVLP does reduce the amount that gets out of the case - but
not completely. (not helped by other piercings through the case like
by the blade height adjust wheel that let air be sucked in via
alternate routes).

I found just adding a bit of tube split round the blade where it
exits the underside of the table, was quite effective on this
contraption:

http://wiki.diyfaq.org.uk/index.php/...awbench#In_Use

That might not be too difficult to mount such that it moves in
sympathy with the blade tilt.


I'm moving towards using a good LVHP almost everywhere (with cyclone,
50mm plastic ducting and home-made blast gates) and only using the
HVLP for the planer thicknesser, and maybe the (rarely used) wood
lathe. I suppose, if I ever get around to inventing something, a dust
catcher for the chop saw might be HVLP as well.

IME HVLP shines for really high volume dust or chip creation (so
planners / thicknessers), and anything where its difficult to catch the
dust in something first and need to rely on really high speed airflow to
capture stuff being ejected from a blade tip.

Yes, HV for chips and large areas (chop saw), and HP for dust. I
upgraded my bandsaw to a Sabre-350 a while ago, the saw is great but the
dust collection is just a 100mm port into the lower casing - the top of
that casing only has a hole for the blade so most of the dust falls on
the floor; one day I'll make a cowl to go directly under the table and
switch it to LVHP. Ooo, perhaps this is the justification for a 3D
printer :-)

On 17/04/2021 09:58, wrote:
On 17/04/2021 01:11, John Rumm wrote:
On 16/04/2021 11:11, wrote:
On 15/04/2021 14:03, John Rumm wrote:
On 15/04/2021 09:08, wrote:

I think about improving DE from time to time (whenever I'm
cleaning-up after a messy job) but don't seem to find the necessary
tuit. My saw has a small hose from the crown guard (hinged on the
riving knife) that goes inside and joins the under-saw 50mm hose to
come out to a 100mm port that I connect to my 2HP HVLP cyclone
extractor. I frequently operate without the crown guard(!!) so plug
the crown guard hose.

One of the problems you might find with the smaller hose up top is
that its not as well suited to the HVLP extractor because of its
higher back pressure. Some people find running a separate LVHP
collector (e.g a shop vac style collector) just for the top hose
works better.
Yes, a little experimentation makes it seem that LVHP is better for
both top and bottom with the current internal plumbing.

I'd like to devise a pivoting and self-adjusting crown guard that's
suspended from a hollow tube that's attached to the saw in some way
and can be used for DE. The crown extraction would be connected to
the under-saw hose with a throttle'able Y connection and then go to
the LVHP extractor.
Issues: how to make the suspension rigid enough (but allow the saw
to be moved), how to improve collection beneath the saw, ...
Suggestions and comments invited.

There are quite a few examples of this kind of thing about - most
are quite large since they need to reach over the saw from far
enough away as to not curtail the maximum size of sheet you can
process.

https://wayofwood.com/diy-tablesaw-o...d-blade-guard/

or

https://www.axminstertools.com/axmin...e-guard-104504



Thanks for those - thought-provoking and similar to what I had in
mind (but I can't believe Axminster sell many at that price)

Probably not - and there are probably cheaper alternatives about. It
was more just an example. Some of the saw makers do their own ones as
well.



You may find that building a cowl to mount under the table to
enclose as much of the blade as you can (either fixed to the
trunnions so that it an tilt, or just wide enough that it can
accommodate the tilt, and connecting that to the HVLP collector will
increase the air speed under the blade high enough that it can
capture everything flying off the tips of the blade, before it gets
a chance to escape again.

My saw was basically designed to just dump dust into its base for
later manual removal. However I added a 4" port to it. Running that
into the HVLP does reduce the amount that gets out of the case - but
not completely. (not helped by other piercings through the case like
by the blade height adjust wheel that let air be sucked in via
alternate routes).

I found just adding a bit of tube split round the blade where it
exits the underside of the table, was quite effective on this
contraption:

http://wiki.diyfaq.org.uk/index.php/...awbench#In_Use

That might not be too difficult to mount such that it moves in
sympathy with the blade tilt.


I'm moving towards using a good LVHP almost everywhere (with cyclone,
50mm plastic ducting and home-made blast gates) and only using the
HVLP for the planer thicknesser, and maybe the (rarely used) wood
lathe. I suppose, if I ever get around to inventing something, a dust
catcher for the chop saw might be HVLP as well.

IME HVLP shines for really high volume dust or chip creation (so
planners / thicknessers), and anything where its difficult to catch
the dust in something first and need to rely on really high speed
airflow to capture stuff being ejected from a blade tip.

Yes, HV for chips and large areas (chop saw), and HP for dust. I
upgraded my bandsaw to a Sabre-350 a while ago, the saw is great but the
dust collection is just a 100mm port into the lower casing - the top of
that casing only has a hole for the blade so most of the dust falls on
the floor; one day I'll make a cowl to go directly under the table and
switch it to LVHP. Ooo, perhaps this is the justification for a 3D
printer :-)

My EB band-saw is similar - 100mm port on the back of the bottom case.
In reality it works to some extent - it seems to stop any dust getting
recirculated round and dropped out of the top housing, and there is a
grid of holes around the table inset that allows some dust to get sucked
away. However its far from perfect. A cowl around the underside could
work well.


--
Cheers,

John.

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