High pressure vs low pressure

On 27 Dec 2006 07:21:38 -0800, [email protected] wrote:

>Hi Guys,
>
>I am looking at adding a dust collection system to my workshop when I
>move house in Jan.I want to build a cyclone dust collection system
>based on Bill Pentz design, I'll make the blower etc too. These systems
>are high volume low pressure units and are great for big tools with the
>wide dust extraction pipes.
>
>So here is the question:
>
>These big systems seem to work great for table saw, jointer and other
>large tools, but is it better to use a shopvac or similar for the
>random orbital and plunge router? Or can I use the big extractor and
>use a thinner hose (which lowers the flow rate)
>
>Any advice will be welcome...
>Brent

I've tried it both ways on portable sanders and can't say I notice
much difference. Haven't tried with a router. When I use the big
collector with small tools with small hoses, I leave another port open
so the collector isn't starved for air.

Paul F.

I have both a DC (Jet 1.5 HP Canister model) and Fein shop vac. The Fein
replaced a Ridgid shop vac. I would not want to go back to the noise of the
Ridgid. I do not need ear protection with the Fein.

I would not want to give up either unit. They have their designed uses and
in my observation are not interchangable.

DC is great where I need high volume, low pressure. Typically due to being
unable to efficiently shroud the item generating the dust. Examples are
table saw, router table, radial arm saw.

I use the Fein with the Random Orbital Sander, Palm Sander which are both
designed for high pressure, low volume dust removal, due to the relatively
high efficiency of the collection shroud. I think trying to connect a 4in
DC hose via reducers for such use will result in very small air flows and
therefore inefficient dust removal.

I also use the Fein for general shop dust cleanup. The smaller hose is
easier to move around.

Dave Paine.

<[email protected]> wrote in message
news:[email protected]...
> Hi Guys,
>
> I am looking at adding a dust collection system to my workshop when I
> move house in Jan.I want to build a cyclone dust collection system
> based on Bill Pentz design, I'll make the blower etc too. These systems
> are high volume low pressure units and are great for big tools with the
> wide dust extraction pipes.
>
> So here is the question:
>
> These big systems seem to work great for table saw, jointer and other
> large tools, but is it better to use a shopvac or similar for the
> random orbital and plunge router? Or can I use the big extractor and
> use a thinner hose (which lowers the flow rate)
>
> Any advice will be welcome...
> Brent
>

"Stephen M" <[email protected]> wrote in message
news:[email protected]...
>>> These big systems seem to work great for table saw, jointer and other
>>> large tools, but is it better to use a shopvac or similar for the
>>> random orbital and plunge router? Or can I use the big extractor and
>>> use a thinner hose (which lowers the flow rate)
>
> I have the big DC connected to a router table and it works fine. However,
> I would think that the big hose would be *way* too cumbersome to attach to
> a mobile tool.

My dust collection is different from most. I use 20' of flex hose and
attach it to what ever tool I am using.


> I tried reducing the dust collector and attaching it to my shop vac hose
> once. It performed poorly.


> I think if you reduce the line right at the end it works pretty well; a
> long narrow hose does not work so well.
>
> FWIW the integrated dust collection (internal fan to bag) on my Makita 5"
> ROS actually works pretty well. It collects maybe 75%. With a suction
> assist, even a modest one, I suspect it would be very effective.

I use a 20" fan at may back for dust extraction when I sand. ;~)

>> These big systems seem to work great for table saw, jointer and other
>> large tools, but is it better to use a shopvac or similar for the
>> random orbital and plunge router? Or can I use the big extractor and
>> use a thinner hose (which lowers the flow rate)

I have the big DC connected to a router table and it works fine. However, I
would think that the big hose would be *way* too cumbersome to attach to a
mobile tool.

I tried reducing the dust collector and attaching it to my shop vac hose
once. It performed poorly.

I think if you reduce the line right at the end it works pretty well; a long
narrow hose does not work so well.

FWIW the integrated dust collection (internal fan to bag) on my Makita 5"
ROS actually works pretty well. It collects maybe 75%. With a suction
assist, even a modest one, I suspect it would be very effective.

Steve

On Wed, 27 Dec 2006 07:21:38 -0800, brent wrote:

> Hi Guys,
>
> I am looking at adding a dust collection system to my workshop when I
> move house in Jan.I want to build a cyclone dust collection system
> based on Bill Pentz design, I'll make the blower etc too. These systems
> are high volume low pressure units and are great for big tools with the
> wide dust extraction pipes.
>
> So here is the question:
>
> These big systems seem to work great for table saw, jointer and other
> large tools, but is it better to use a shopvac or similar for the
> random orbital and plunge router? Or can I use the big extractor and
> use a thinner hose (which lowers the flow rate)
>
> Any advice will be welcome...

If you're using the ROS in a fixed location then build a downdraft table
and connect it to the dust collector with an additional hose to the ROS
(that one you can just run into the main hose or pipe about four feet or
so and it should get plenty of suction, no fancy fittings needed, but
strap it down so the DC doesn't swallow it).

If you're moving it around go with the shop vac if it has a decent amount
of power--trying to run a DC with just a 1-1/2" or so hose isn't going to
work very well--it will suck fine through that hose but then the dust etc
may not move through the larger plumbing due to reduced flow velocity.

> Brent

--

--John

to email, dial "usenet" and validate

(was jclarke at eye bee em dot net)

<[email protected]> wrote in message
news:[email protected]...
> Hi Guys,
>
> I am looking at adding a dust collection system to my workshop when I
> move house in Jan.I want to build a cyclone dust collection system
> based on Bill Pentz design, I'll make the blower etc too. These systems
> are high volume low pressure units and are great for big tools with the
> wide dust extraction pipes.
>
> So here is the question:
>
> These big systems seem to work great for table saw, jointer and other
> large tools, but is it better to use a shopvac or similar for the
> random orbital and plunge router? Or can I use the big extractor and
> use a thinner hose (which lowers the flow rate)


You can use the dust collector for the small stuff also. I have a reducer
at my router table fence and when adjusted for a cut that will permit
suction the dust collector works very well. Placed near the bit in a drill
press it catches most every thing also straight into the 4" opening.