Would anyone care to recommend a supplier of ducting suitable for a
small woodworking shop? I have the extractor and bagging system but now
need the central spine, branches, gates and flexible pipe to connect up
the machines.

Google throws up endless possibilities with wildly varying prices.

regards
--
Tim Lamb

Tim Lamb wrote:
Would anyone care to recommend a supplier of ducting suitable for a
small woodworking shop? I have the extractor and bagging system but
now need the central spine, branches, gates and flexible pipe to
connect up the machines.

Google throws up endless possibilities with wildly varying prices.

Axminster stock of lot of this stuff.

HTH


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk
01634 717930
07850 597257

Axminster stock of lot of this stuff.

Cheap solution is soil pipe, but I'm told that transparent rigid
tubing is a huge advantage when you get a blockage.

Cheap flexi tends to encourage blockages too - I tend to use a loose
100mm hose to clear up, and keep telling myself to upgrade.

On 2008-03-29 22:23:09 +0000, Tim Lamb said:

Would anyone care to recommend a supplier of ducting suitable for a
small woodworking shop? I have the extractor and bagging system but now
need the central spine, branches, gates and flexible pipe to connect up
the machines.

Google throws up endless possibilities with wildly varying prices.

regards

Nordfab QF Duct.

http://www.danthermfiltration.com/Pr...l/Ducting.aspx

There's

a downloadable brochure.

Contact is

http://www.danthermfiltration.co.uk/Contact-19.aspx

Try their Leeds office.

They can also supply flexible hose and large Jubilee clips to fix it as
well as being able to fabricate particular combinations of outlets - I
needed a couple of those - very inexpensively. Their blast gates are
excellent, made by sandwiching a metal sheet between nylon components
to seal. Hint. Ask for a discount.

Felder also sells a good range of flexible hoses.

http://mk.felder-gruppe.at/?page=shop_node&node=326

and similar duct.

http://mk.felder-gruppe.at/?page=shop_node&node=193


This is a good quality product range whereby sections are clipped
together with sprung clipped rings. It is important to do a proper
design for the ductwork, and there are web sites covering that. The
key is to have enough air flow in order to move the material, while at
the same time having enough velocity so that chips don't settle in the
ducting. Just hacking together is highly likely to bring
disappointment.

I have an American manufactured cyclone extractor which has a 7 inch
intake duct. This is transitioned immediately to proper metric sizes
(140mm to begin with) using a short length of flexible hose. After a
couple of metres this splits into two 160mm branches and these then go
to 120mm closer to machine connecion points. My combination machine
needs 120mm for the saw, the spindle moulder and the planer/thicknesser
and then additionally 80mm for the spindle moulder and 50mm for the saw
guard extraction. I've implemented three wall positions plus a
ceiling one which each have 120mm gates and then there are 80mm gates
for the rest. The bandsaw also needs 120mm.

All of this works very well indeed - extraction is good and no
blockages, so no design errors.

Another advantage of the Nordfab QF is that it can be demounted and
modified very easily. So for example, I've added an additional 120mm
connection point for a downdraught table for sanding.

A completely alternative approach is to just use flexible hose for the
lot. If that's done, then it's important to buy decent industrial
hose because it's smoother internally. The cheap stuff, apart from
being flimsy tends to have ridges inside and will impede air flow.

Don't be tempted to buy cheap airconditioning grade duct. A half
reasonable extractor is perfectly able to collapse it. As a minimum,
extraction grade duct must be used even if you decide to go for a type
that is taped together at the joints.

On 2008-03-29 23:02:07 +0000, " said:


Axminster stock of lot of this stuff.

Cheap solution is soil pipe, but I'm told that transparent rigid
tubing is a huge advantage when you get a blockage.

There is a small risk of static build up, and with fine dust, explosion
with soil pipe. As a minimum, if it must be used, it should be
sprayed with a metallic paint and grounded.

100mm pipe over more than a very few metres, even if connected to a
100mm extractor, will have too much internal resistance and spoil air
flow. If the extractor has a good enough pressure/flow curve, it's
better to go for 125 or 150mm duct. However, 150mm soil pipe is
getting expensive.



Cheap flexi tends to encourage blockages too - I tend to use a loose
100mm hose to clear up, and keep telling myself to upgrade.

Industrial grade is far better and also tends to be static treated
which avoids catching of dust etc on the sides.

In message , Tim Lamb
writes
Would anyone care to recommend a supplier of ducting suitable for a
small woodworking shop? I have the extractor and bagging system but now
need the central spine, branches, gates and flexible pipe to connect up
the machines.

Google throws up endless possibilities with wildly varying prices.

OK chaps.

Plenty to be going on with:-)

I had found Felder which seems an up-market product.

My extractor came second hand with a burned out single phase motor so I
don't have technical info on flow/pressure curves. I have fitted a 3 ph.
motor which should survive over loading better. (I suspect the previous
user had forgotten to empty the collecting bags and stalled the fan).

I had been comparing prices with ventilation duct and take the point
about collapsing the walls.

The whole building is only just over 12m long so 100mm duct may do. I
will look out for design info.

Thanks.

regards to all
--
Tim Lamb

On Sat, 29 Mar 2008 23:18:43 +0000, Andy Hall wrote:

There is a small risk of static build up, and with fine dust, explosion
with soil pipe.

Absolute and utter bolllocks.

On 2008-03-30 15:50:43 +0100, Andy Dingley said:

On Sat, 29 Mar 2008 23:18:43 +0000, Andy Hall wrote:

There is a small risk of static build up, and with fine dust, explosion
with soil pipe.

Absolute and utter bolllocks.

www.hse.gov.uk/pubns/wis1.pdf

www.hse.gov.uk/pubns/wis32.pdf

http://www.dir.ca.gov/title8/4324.html

On Sun, 30 Mar 2008 16:31:12 +0100
Andy Hall wrote:

On 2008-03-30 15:50:43 +0100, Andy Dingley said:

On Sat, 29 Mar 2008 23:18:43 +0000, Andy Hall wrote:

There is a small risk of static build up, and with fine dust, explosion
with soil pipe.

Absolute and utter bolllocks.

www.hse.gov.uk/pubns/wis1.pdf

www.hse.gov.uk/pubns/wis32.pdf

http://www.dir.ca.gov/title8/4324.html



Ah, Governments, we all believe them then. Wonder which pipe
manufacturer took who on holiday?

Not to say you aren't right Andy, but this ain't proof.

R.

TheOldFellow wrote:
On Sun, 30 Mar 2008 16:31:12 +0100
Andy Hall wrote:

On 2008-03-30 15:50:43 +0100, Andy Dingley said:

On Sat, 29 Mar 2008 23:18:43 +0000, Andy Hall wrote:

There is a small risk of static build up, and with fine dust, explosion
with soil pipe.
Absolute and utter bolllocks.
www.hse.gov.uk/pubns/wis1.pdf

www.hse.gov.uk/pubns/wis32.pdf

http://www.dir.ca.gov/title8/4324.html



Ah, Governments, we all believe them then. Wonder which pipe
manufacturer took who on holiday?

Not to say you aren't right Andy, but this ain't proof.

R.

Made me think of this:

http://www.niepce.com/pagus/pireus1.html

--
Rod

Hypothyroidism is a seriously debilitating condition with an insidious
onset.
Although common it frequently goes undiagnosed.
www.thyromind.info www.thyroiduk.org www.altsupportthyroid.org

www.hse.gov.uk/pubns/wis32.pdf

http://www.dir.ca.gov/title8/4324.html
^^^^^^^

Not to say you aren't right Andy, but this ain't proof.

Odd to see that the State of California is in league with the Health
and Safety Executive.

Maybe they threatened to set the Governator on our HSE boys if they
didn't go along with perpetuating this myth.

What else are they lying about? Is asbestos dust actually good for
you?

On 2008-03-30 16:46:26 +0100, TheOldFellow said:

On Sun, 30 Mar 2008 16:31:12 +0100
Andy Hall wrote:

On 2008-03-30 15:50:43 +0100, Andy Dingley said:

On Sat, 29 Mar 2008 23:18:43 +0000, Andy Hall wrote:

There is a small risk of static build up, and with fine dust, explosion
with soil pipe.

Absolute and utter bolllocks.

www.hse.gov.uk/pubns/wis1.pdf

www.hse.gov.uk/pubns/wis32.pdf

http://www.dir.ca.gov/title8/4324.html



Ah, Governments, we all believe them then. Wonder which pipe
manufacturer took who on holiday?

Not to say you aren't right Andy, but this ain't proof.

R.

I wasn't setting out to provide *proof* as such, only to say that it is
considered that there is a risk.

For the sake of a small cost saving from using proper metal duct, vs.
plastic, the prospect of a fire isn't worth the saving even if the risk
is small

One should also point out that when using extractors, it's important to
watch out for metal items being cut or sparking if they contact a
moving part and ending up in the waste bin. I always make a point of
checking that before leaving the workshop for the day. Other issues
are to keep the place as clean as possible and to store solvents
sensibly.

On Mar 30, 6:33*pm, " wrote:
www.hse.gov.uk/pubns/wis32.pdf
http://www.dir.ca.gov/title8/4324.html

* * * * * * * * * * * * *^^^^^^^

Not to say you aren't right Andy, but this ain't proof.

Odd to see that the State of California is in league with the Health
and Safety Executive.

Maybe they threatened to set the Governator on our HSE boys if they
didn't go along with perpetuating this myth.

This has bee covered befo

http://groups.google.com/group/uk.d-...se_frm/thread/
f6c3d2371c664c76/2b570cc57eda4cf4?lnk=st&q=%22dust+collector
%22+static#

IME safety standards can sometimes be fairly arbitrary rather than
based on proper risk analysis or rationale.

cheers,
Pete.

On 30 Mar, 16:31, Andy Hall wrote:

There is a small risk of static build up, and with fine dust, explosion
with soil pipe.

Absolute and utter bolllocks.

www.hse.gov.uk/pubns/wis1.pdf

www.hse.gov.uk/pubns/wis32.pdf

http://www.dir.ca.gov/title8/4324.html

Where do any of those cite a problem with static discharges causing an
explosion in wood dust?

The UK advisory sheets don't claim this. One of them advises bonding,
which is reasonable advice for a staff comfort PoV. The Califonian
code requires bonding, but doesn't say why.

No-one disputes that dust flow causes static discharges. These are an
annoyance.

However:

* You can't initiate a wood dust explosion with a static discharge,
such as is frequently generated by non-conductive ducting.

* You can't initiate a propagating wood dust explosion with a spark
(NB a "spark" in the precise sense of the field of electrostatic
hazard analysis, not merely a discharge), such as might be generated
by a suitable arrangement of conductive pipe separated by insulators.

* You can very easily start a wood dust fire from any number of
workshop hazards as an ignition source.

* You can cause an explosion in a duct system by getting solvent
vapour into it. One of the most common sources of such explosion is to
design a safe system for extracting solvent vapour, then later
switching solvents to using toluene (which is infamously sensitive to
ignition).


"Static discharge causes wood dust explosions" is a red herring. It
doesn't happen. It's not hard to show that it _can't_ happen (the
available energies are simply too low). In particular it's an FAQ to
most of those bits of usenet associated with either wood, dust, safety
or electrostatics.

Worry about the real stuff. Smouldering embers going up the pipe is
what's going to get you, not static discharges. Or else using toluene.

On 2008-03-31 12:16:59 +0100, Andy Dingley said:

On 30 Mar, 16:31, Andy Hall wrote:

There is a small risk of static build up, and with fine dust, explosion
with soil pipe.

Absolute and utter bolllocks.

www.hse.gov.uk/pubns/wis1.pdf

www.hse.gov.uk/pubns/wis32.pdf

http://www.dir.ca.gov/title8/4324.html

Where do any of those cite a problem with static discharges causing an
explosion in wood dust?

Reasons can be this, charge build up on machines or deposition on duct
eventually causing blockages. Perhaps there are others.


The UK advisory sheets don't claim this. One of them advises bonding,
which is reasonable advice for a staff comfort PoV. The Califonian
code requires bonding, but doesn't say why.

Since one can and should ground machines, I am not sure where comfort
would enter into it.



No-one disputes that dust flow causes static discharges. These are an
annoyance.

However:

* You can't initiate a wood dust explosion with a static discharge,
such as is frequently generated by non-conductive ducting.

* You can't initiate a propagating wood dust explosion with a spark
(NB a "spark" in the precise sense of the field of electrostatic
hazard analysis, not merely a discharge), such as might be generated
by a suitable arrangement of conductive pipe separated by insulators.

I don't have evidence that this is impossible.



* You can very easily start a wood dust fire from any number of
workshop hazards as an ignition source.

Agreed


* You can cause an explosion in a duct system by getting solvent
vapour into it. One of the most common sources of such explosion is to
design a safe system for extracting solvent vapour, then later
switching solvents to using toluene (which is infamously sensitive to
ignition).

Also agreed.



"Static discharge causes wood dust explosions" is a red herring. It
doesn't happen. It's not hard to show that it _can't_ happen (the
available energies are simply too low). In particular it's an FAQ to
most of those bits of usenet associated with either wood, dust, safety
or electrostatics.

This all seems to be based on an article by one Dr Rod Cole a maths PhD
and meteorologist

http://home.comcast.net/~rodec/woodw.../DC_myths.html

His arguments make compelling reading, and may even be correct;
however, even he doesn't say *definitively* that explosions *can't*
happen, "only that home shop DC explosions are somewhere between
extraordinarily rare and nonexistent."

Given even that scenario, and being faced between the choice of using
PVC and doing the job properly with metal duct, to me the choice is
clear. If risk can be reduced reasonably, then reduce it.

Notwithstanding this, 100mm soil pipe is too small to use for any
reasonably sized duct system and 150mm and fittings costs as much as or
more than using metal. That's before one considers the lack of
suitable fittings.



Worry about the real stuff.

All of this is real stuff. The question is the degree of risk.


Smouldering embers going up the pipe is
what's going to get you, not static discharges. Or else using toluene.

I would agree that risks associated with embers, bits of metal and
solvent are higher, but don't exclude others than can be reasonably
reduced.

On 31 Mar, 13:24, Andy Hall wrote:

"Static discharge causes wood dust explosions" is a red herring. It
doesn't happen. It's not hard to show that it _can't_ happen (the
available energies are simply too low). In particular it's an FAQ to
most of those bits of usenet associated with either wood, dust, safety
or electrostatics.

This all seems to be based on an article by one Dr Rod Cole a maths PhD
and meteorologist

http://home.comcast.net/~rodec/woodw.../DC_myths.html

Actually it's based on an applied physics degree and some experience
of doing risk analysis for chem / pharm labs, but let's not let that
get in the way of citing a few random web links instead 8-)

Rod Cole's page is a good one, and his explanation of discharge types
is clear and useful (although 'merkins count 6 here and non-meteo
Europeans generally only count either 4 or 5). "Spark" vs. "Discharge"
is a significant distinction worth drawing. If there's one thing worse
than a plastic duct, it's a mixed metal and plastic duct.

If you don't want to believe random webbage, then try reading the
electrostatics literature. If you search news:rec.woodworking, you
ought to find literature reviews that I've posted there myself. Be
warned though, you'll need a uni library or similar as most of this
stuff isn't found on the free sections of general reference shelves.

On 30 Mar, 09:23, Tim Lamb wrote:

My extractor came second hand with a burned out single phase motor so I
don't have technical info on flow/pressure curves. I have fitted a 3 ph.
motor which should survive over loading better. (I suspect the previous
user had forgotten to empty the collecting bags and stalled the fan).

DC fans shouldn't be that class of jobs where a 3 phase motor has a
great deal to offer over a single phase. They must have _really_
screwed things up!

Only time I've ever seen a stalled fan on a DC was when someone left
the ring clamp from the filter wedged in it.

On 2008-03-31 13:59:45 +0100, Andy Dingley said:

On 31 Mar, 13:24, Andy Hall wrote:

"Static discharge causes wood dust explosions" is a red herring. It
doesn't happen. It's not hard to show that it _can't_ happen (the
available energies are simply too low). In particular it's an FAQ to
most of those bits of usenet associated with either wood, dust, safety
or electrostatics.

This all seems to be based on an article by one Dr Rod Cole a maths PhD
and meteorologist

http://home.comcast.net/~rodec/woodw.../DC_myths.html

Actually it's based on an applied physics degree and some experience
of doing risk analysis for chem / pharm labs, but let's not let that
get in the way of citing a few random web links instead 8-)


Rod Cole's page is a good one, and his explanation of discharge types
is clear and useful (although 'merkins count 6 here and non-meteo
Europeans generally only count either 4 or 5). "Spark" vs. "Discharge"
is a significant distinction worth drawing. If there's one thing worse
than a plastic duct, it's a mixed metal and plastic duct.

If you don't want to believe random webbage, then try reading the
electrostatics literature. If you search news:rec.woodworking, you
ought to find literature reviews that I've posted there myself. Be
warned though, you'll need a uni library or similar as most of this
stuff isn't found on the free sections of general reference shelves.

The trouble is that the web sites and newsgroups are littered with
conflicting information.

Cole appears to have some level of credibility, I agree, but still does
not definitively and wisely say that it's impossible for an explosion
to happen as a result of static. It also represents one perhaps
reasonable (or not) set of data among a volume saying the opposite.
Then we have H&S recommendations not to use plastic duct.

As you say, to research that properly and to form an opinion would
require a trip to the unversity library and quite a few hours of
research and maths.

That would still only take one to the point of reasonable doubt.

Since 100mm plastic soil pipe is unsuitable for dust extraction on all
but the smallest systems anyway, and larger sizes are as or more
expensive than the proper metal stuff, then the point is academic
anyway and I decided not to waste time on it.

On 31 Mar, 14:41, Andy Hall wrote:

As you say, to research that properly and to form an opinion would
require a trip to the unversity library and quite a few hours of
research and maths.

You can't afford Encyc. CPD (two dozen volumes, hundred quid each) and
you won't find a copy of Glor as it's OOP and scarce. Luttgens'
"Electrostatic Hazards" is the only one that's even vaguely
affordable. That's also a bit qualitative, not quantitative, so I
doubt you'd be convinced by it anywayy

On 2008-03-31 16:39:08 +0100, Andy Dingley said:

On 31 Mar, 14:41, Andy Hall wrote:

As you say, to research that properly and to form an opinion would
require a trip to the unversity library and quite a few hours of
research and maths.

You can't afford Encyc. CPD (two dozen volumes, hundred quid each) and
you won't find a copy of Glor as it's OOP and scarce. Luttgens'
"Electrostatic Hazards" is the only one that's even vaguely
affordable. That's also a bit qualitative, not quantitative, so I
doubt you'd be convinced by it anywayy

Exactly, so cutting it short and taking the pragmatic approach of using
metal duct is the thing to do, for other reasons as well.

On 31 Mar, 17:24, Andy Hall wrote:

Exactly, so cutting it short and taking the pragmatic approach of using
metal duct is the thing to do, for other reasons as well.

Although if you read some of Luttgens' case studies, you will find
examples (with solvents, not wood dust) where switching from non-
conductive plastic to metal _caused_ explosions.

In message 47f11057@qaanaaq, Andy Hall writes
On 2008-03-31 16:39:08 +0100, Andy Dingley said:

On 31 Mar, 14:41, Andy Hall wrote:

As you say, to research that properly and to form an opinion would
require a trip to the unversity library and quite a few hours of
research and maths.
You can't afford Encyc. CPD (two dozen volumes, hundred quid each)
and
you won't find a copy of Glor as it's OOP and scarce. Luttgens'
"Electrostatic Hazards" is the only one that's even vaguely
affordable. That's also a bit qualitative, not quantitative, so I
doubt you'd be convinced by it anywayy

Exactly, so cutting it short and taking the pragmatic approach of using
metal duct is the thing to do, for other reasons as well.

Gentlemen!

I shall be using 150mm metal duct for the main overhead run. The spigot
on my fan is 150mm o/d so it will require, at least, some flexible
piping for the final connection.

I have not decided about the actual machinery connections. I don't have
a spindle moulder so the main *dust* generators are the bench saw and
the planer/thicknesser. I have a Wadkin pull over saw and a powered
morticer but foresee problems in gathering the chips.

It would be nice to collect the output from various hand tools as well.
I plan to seek council from my woodworking tenant who has overcome all
these problems:-)

regards




--
Tim Lamb

In message
,
Andy Dingley writes
On 30 Mar, 09:23, Tim Lamb wrote:

My extractor came second hand with a burned out single phase motor so I
don't have technical info on flow/pressure curves. I have fitted a 3 ph.
motor which should survive over loading better. (I suspect the previous
user had forgotten to empty the collecting bags and stalled the fan).

DC fans shouldn't be that class of jobs where a 3 phase motor has a
great deal to offer over a single phase. They must have _really_
screwed things up!

Yes. I don't think there was any overload protection other than the
supply fuses. The start winding had some shorted turns and the capacitor
was mainly converted to charcoal. A re-wind was roughly the same cost as
a new 3ph. motor and I already had a suitable starter.

Only time I've ever seen a stalled fan on a DC was when someone left
the ring clamp from the filter wedged in it.

Umm... I re-assembled the unit from a big box of bits and have not come
across anything intended to stop chunks of wood reaching the fan.
Presumably there should be a grid of some sort? If so, what sort of mesh
size?

regards

--
Tim Lamb

On 2008-03-31 20:43:37 +0100, Tim Lamb said:

In message 47f11057@qaanaaq, Andy Hall writes
On 2008-03-31 16:39:08 +0100, Andy Dingley said:

On 31 Mar, 14:41, Andy Hall wrote:

As you say, to research that properly and to form an opinion would
require a trip to the unversity library and quite a few hours of
research and maths.
You can't afford Encyc. CPD (two dozen volumes, hundred quid each) and
you won't find a copy of Glor as it's OOP and scarce. Luttgens'
"Electrostatic Hazards" is the only one that's even vaguely
affordable. That's also a bit qualitative, not quantitative, so I
doubt you'd be convinced by it anywayy

Exactly, so cutting it short and taking the pragmatic approach of using
metal duct is the thing to do, for other reasons as well.

Gentlemen!

I shall be using 150mm metal duct for the main overhead run. The spigot
on my fan is 150mm o/d so it will require, at least, some flexible
piping for the final connection.

I have not decided about the actual machinery connections. I don't have
a spindle moulder so the main *dust* generators are the bench saw and
the planer/thicknesser. I have a Wadkin pull over saw and a powered
morticer but foresee problems in gathering the chips.

It would be nice to collect the output from various hand tools as well.
I plan to seek council from my woodworking tenant who has overcome all
these problems:-)


You can do that to a degree, but the characteristics of dust extractor
are rather different to a vacuum cleaner. The latter is able to
deliver a lot more vacuum on a small hose.

A larger DC won't give good results with very long lengths of narrow
hose. For example, on my saw guard, I initially ran a length of 50mm
hose from a ceiling mounted 100mm blast gate followed by a 100x50
reducer. The drop was about 2.5m. It worked OK but I thought it
could do better. I changed it to 80mm hose with an 80x50mm reducer at
the guard itself and it was substantially better.

For hand tools like sanders and routers, I've found that up to 1.5m or
so of 38mm hose is OK hooked up to the DC.

Andy Hall wrote:
SNIP
You can do that to a degree, but the characteristics of dust
extractor are rather different to a vacuum cleaner. The latter is
able to deliver a lot more vacuum on a small hose.

Pedant mode on
Thats suction, not vacuum.
Pedant mode off.

:-)


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk
01634 717930
07850 597257

On Mon, 31 Mar 2008 20:43:37 +0100, Tim Lamb
wrote:

I have not decided about the actual machinery connections. I don't have
a spindle moulder so the main *dust* generators are the bench saw and
the planer/thicknesser.

My 4" chip collector rig is on the thicknesser, the 2" (shop vac +
cyclone) dust sucker is on either the bandsaw or the router table. The
saw and the jointer just gravity dump into a box.

The thicknesser can fill 10 sackfuls in a day, if I'm really working.
Nothing else comes close. I sometimes blow dust off the top of the
cabinet saw, but otherwise I just don't have a problem with it. I empty
the cyclone annually.

Dust collection on the morticer is by swearing loudly at the the chisel.