Thread: Alternative Dust Extraction Solution

Mick, if height really is just impossible with a CV, and you are looking at a non-cyclone DC, you might consider the Felder AF22 D-200. Similar price and power/voltage requirements to the CV, 200mm input line and if placed outside the workshop, you don't need the ultra fine filtration. It is also definitely quieter.

I've decided on the CVMax, because at 2700mm I've got the clearance, but I think the Felder's flows and static suction pressure are up there too.

Just a thought.

Cheers,

Mark

Originally Posted by markkr

Mick, if height really is just impossible with a CV, and you are looking at a non-cyclone DC, you might consider the Felder AF22 D-200. Similar price and power/voltage requirements to the CV, 200mm input line and if placed outside the workshop, you don't need the ultra fine filtration. It is also definitely quieter.

I've decided on the CVMax, because at 2700mm I've got the clearance, but I think the Felder's flows and static suction pressure are up there too.

Just a thought.

Cheers,

Mark

Mark,

much appreciated for above. In my searches, I had not come across these (they obviously don't pay google enough )so will take a closer look. To be honest, I'd like to go down the cyclone route to simplify my cleaning but am not sure if the one that will hopefully fit MWE-351AX Auto Cyclone - Major Woodworking Equipment will do the job good enough. Certainly I don't expect the 2hp ones (which I know will fit) to be good enough. Compromises everywhere!!!

cheers

Mick

A generic question in regards to buying a DC - particularly a 3hp one. If I only have single phase input (which is true) am I right in understanding that if I saw 2 x 3hp machines with one that was single phase and the other 3-phase then ......

- assuming the 3-phase can be wired to run on 240-volts

- in buying the single phase I will probably need to deal with getting a 15-amp 'socket'
- in buying the 3-phase, I would :
- still probably require a 15-amp 'socket'
- need a VFD to convert from single to 3-phase
- can run the 3-phase at 60hz, getting approximately 20% more power
- if the two were the same price then for approximately $200 (assuming I needed to get a sparky in anyway) I get 20% more power

this may have already been answered but I am still getting my head around everything so am hoping that I might have finally understood something

thanks

Mick

Originally Posted by mick59wests

A generic question in regards to buying a DC - particularly a 3hp one. If I only have single phase input (which is true) am I right in understanding that if I saw 2 x 3hp machines with one that was single phase and the other 3-phase then ......

- assuming the 3-phase can be wired to run on 240-volts

- in buying the single phase I will probably need to deal with getting a 15-amp 'socket'
- in buying the 3-phase, I would :
- still probably require a 15-amp 'socket'
- need a VFD to convert from single to 3-phase
- can run the 3-phase at 60hz, getting approximately 20% more power
- if the two were the same price then for approximately $200 (assuming I needed to get a sparky in anyway) I get 20% more power

Technically speaking, "Power" and "flow" are two different things. At 60 Hz the motor will draw ~40% more electrical power but generate only 20% more air flow and make a lot more noise.

As for the rest you need to go back and read my post on motors.

A budget VFD will convert single phase 240 V to 3 phase 240 V
BUT
Not all 3 phase motors will run off the shelf on 240 V 3 phase so you will need to check if the motor is able to do this without internal modification.

If the motor needs to be modified and if you cannot do the modification you will need to pay an electric motor specialist to do it - my guess is $120 to do this.
My bet is your warranty will also not remain valid if this is done.

Originally Posted by Chris Parks

Just what is needed, someone trying to destroy someone else's business and livelehood. Well done Sound Man, let's here three cheers for him,

When there is a commercial vendor, regularly posting on a forum, making comments and recommendations specifically about products he sells.....I will not resile form making balancing comments about the product.

On many forums, such vendors would be banned and ommitted at the first post and or any comments that may show commercial interest would last less than 24 hours without being deleated..

Further.....having been arround for a while, I am sick to death of products, being imported that are not specfcally designed for or at least accomodate australian conditions, and are either disadvantaged in performance or require additional modification or expense to work under our conditions.

If you run a business and can not cope with some factual critisim, I sugest you fold up ya tent and go working for wages.

cheers

Back to other issues.

I consider it plainly rediculous that the motor powering the dust extraction system needs to be bigger than the motor driving a single power tool.

Not many of us have sufficient incomming mains to supply a 3Hp motor for a single machine and a 4 or 5 Hp motor for a dust extractor to serve the dust extraction system....hell most of us will struggle to power a 2hp extractor at the same time.

I consider my self to have a fairly well supplied home workshop, that many people would envy......I have a 40 amp circuit breaker on the submain to my shed.
My sawbench has a 3hp (output) motor fitted with a 20 amp plug and draws about 26 amps cutting light material...it has a peak starting current of around 56 amps.....I have the tools to measure this.
So, ya think I am going to run a 4Hp cyclone......not likley.

As for relative sizes of motors and cyclones.

The idea that a cyclone required only an additional 1Hp....that is very arbitary......

It is reasonable to consider a 5hp motor on a cyclone is more or less equavalent to a 3hp motor on a conventional bagged extractor......apples for apples.......that does not represent small losses,that is 60% increase in power and that represents the difference between a single phase supply and a 3 phase supply.

As for the size and effectivness of smaller cyclones.....the size and proportion realy cant be compromised without loss of efficiency.
Almost without exception commecial cyclones will be compromised for size, because there is very strong buyer resistance on size...and the cost of shipping full size cyclones is just prohibitive.

Either or both, suction loss or seperation efficiency will be compromised and these size reduced commecrial units.
Thus the cyclone will require either more power to drive it or greater attention to the filtering.

I have compared my 2 inch input full sized cyclone, with a very much smaller commercial 2 inch cyclone of a friend and my expectations are confirmed.




As I have posted there are considerable differences, in the flow and efficiency of different models of standard bagged dust extractors.

There is a great deal of difference between a crude cheap 1Hp dust extractor that flows arround 600CFM ( ringin' wet), and an efficient 1.5Hp unit that has larger air paths and more than twice the filtration area and flows 1200CFM......and that is comparing extractors commonly available 10 years ago...and with bags and not pleated cartrige filters.
As I posted before, at the same time most of the 2Hp extractors on the market claimed arround 1200CFM......and had fairly lossy air paths.

Come forward to current times and there are some commonly available extractors that represent significant efficiency gains over extractors of the past.




Then we start with the losses in the ducts.
These losses mount up rapidly.....I don't know if Bill Pentz duct calculator is still live, but it shows how little it takes to introduce massive losses and require very much larger motors.

I have proven the issue of losses in ducting, by work on my own systems.....I have achieved very large improvements in dust extraction efficiency on my table saw by minimising the lengths of duct, removing as much flexible duct as possible and making the paths as straight as possible........and I am talking about duct lengths less than 3 meters.
The duct from my extractor to the case of my saw bench is less than 1.2 meters long and nearly straight.......the airflow at the throat plate is substantial.... I also have an over head guard with 2 x 3 inch hoses fed to a 100mmm pipe...there is considerable airflow arround the blade area......so much so that at times you can see dust driven away from the hole, turn around, go the opposite direction and be sucked away.

The limitation on this system is not the amount of suction or airflow, but the nature of the tool......no matter how much extraction there is the tool will always drive a substantial amount of material away and across the table.....on some cuts more than others...

Start talking about many meters of duct and many bends and fittings......the losses will be massive......the need for a 50% increase in suction motor power to maintain airflow is far from unrealistic...so ya 5Hp blower became a 7Hp blower with not much duct at all......start thowing round a lot of duct and bends and a 100% increase in blower power is far from unreasonable.

So are we talking about sufficient air flow for chip extraction or for capturing Fine invisable dust.
If ya just talking about chip extraction and stopping ya ducts from clogging...that is one thing......if you want sufficient airflow for any chance of fine dust capture and extraction efficiency...... well its not unreasonable to double you air flow expectations.......so now we have gone from a 7Hp motor to a 14Hp motor.

For many tools the idea of any high persentage of dust capture is nothing but a fantasy and invisable dust is the least of ya problems.

If ya got plenty of money and a 3 phase supply...hey knock ya self out.

But for the rest of us that struggle to get a 10 amp general purpose circuit, a single 15 or 20 amp circuit and a lighting circult in our sheds........the idea of cyclones and ducting just will not fly.



Then of course you have the issue with accomodating 4 or 6 inch ducts in ya workshop.......

There was a time when I was all keen about running ducts hither and thither......the more I thaught about it the less practical it looked.
So I just baught a second dust extractor and upgraded the bags on both.....AT the time pleated cartridge filters where still a rich mans game.

Seroulsy....have a look around commercial workshops......the cyclone is well and truly out of favour, because there are so many more effective alternatives these days.

BTW.....I'm not selling cyclones or any other type of dust extractor, nor do I have any unrealistic ideas of workshop hygeen.

My workshop still has its fair share of invisable dust, and plenty of visable dust too.......but I walk about in a world that is dustier that that most days.

cheers
cheers

Originally Posted by soundman

So are we talking about sufficient air flow for chip extraction or for capturing Fine invisable dust.
If ya just talking about chip extraction and stopping ya ducts from clogging...that is one thing......if you want sufficient airflow for any chance of fine dust capture and extraction efficiency...... well its not unreasonable to double you air flow expectations.......so now we have gone from a 7Hp motor to a 14Hp motor.

Soundman,

I hear you, but my experience is otherwise. What was once my most problematic dust producer, the linisher, is further from the cyclone than any other machine. Total duct length is 10 M. According to Bill Pentz's static calculator I have about 7 inches WC of losses to that machine. The measured static pressure is 12 inches. After the hoods were modified, dust collection is nothing short of excellent. A year after installation and I am not getting the kind of significant dust building up on nearby surfaces that was once common, and severe. Linisher Dust Collection - YouTube

The next furthest machine from the cyclone is the table saw, followed by the drop saw. Dust collection is brilliant. Table Saw Overhead Dust Collection.wmv - YouTube Drop Saw dust collection - YouTube

The CV works; not only in theory, but also in practice. The system works very well at catching the very fine dust and the chips with a 3.3 kW (4.4 HP) motor. Suggesting that we might be looking at a 7 or 14 HP motor is contrary to the available evidence. I invite you to visit my shop and see for yourself.

True, I paid about $3,500 for the CV 1800 and ducting etc, but reckon I got value for money. An optimised 2 HP (or thereabouts) system will do a reasonable job, but I wanted better than "reasonable" and was willing to pay the price. For those who are not, or who don't want ducting, the optimised 2 HP system is an inexpensive, workable solution, as you suggested. Seems to me this is a very personal decision. You don't like cyclones. That's fine. You are entitled to your opinion.

I love my CV to death and do not hesitate to recommend it for those who want first-class dust collection and who are willing to spend what I spent to get it.

Again as I said powering up a 15 amp single phase motor just for dust colection seems a little extravagant for most home workshops.

Likewise most of us will baulk at $3500.....pluss labour to install when a pretty fair 2hp single bag extractor and a pleated cartridge filter that will flow arround the 1200cfm can be had for under $1000
If ya want to step up to one of the more efficient two bag 2hp units with 2 pleated cartrige filters flowing in round figures 2000cfm for arround $1500

Unfortunately, no one is importing the higher efficiency 1.5 Hp extractors at this time and these will flow 1200CFM from arround 5 amps single phase

My example is like for like blowers
All sorts of variations occur with different blower configurations.
It likewise very easy to isntal very lossy ducting.

No doubt you are happy with your purchase......you would want to be if you coughed up that sort of cash.

cheers

Yes,

It is a very personal decision. No two woodworkers are exactly alike in their wants and needs, and no two shops are alike.

We certainly agree on a couple of points.
1. It is easy to create significant losses with poor duct design. Port and hood design are just as important.
2. If we pay for first-class dust extraction, the darned thing had better perform. Thankfully, mine does.

One thing I would like to do is to actually measure my airflow ... don't trust any of the manufacturer's claims. Does anyone know of someone in brisbane with decent instruments who could do this for me? Don't feel like buying something I would rarely use. Willing to cough up a few bob for a commercial service if necessary.

One of the interesting things that happened to me was that after the cyclone went in I discovered just how much fine dust the vac produced. At first, all was good. Then as the days rolled on a fine red/brown haze started to appear around the vac. This continued to build up until it was a rather thick layer. As you know, vacs can produce more fine dust that they remove by grinding up bigger particles. This issue was always there, it was just not noticeable when my machines were throwing dust all over the place and the entire shop was dusty. I did nothing at first, just to see what would happen. Sure enough, the layer continued to grow in all directions, and I started to get a thin film of dust quite some distance from the vac. So I banished it outside, under a hood. Problem solved, cheaply and well. I knew this happened. However, until I saw it with my own eyes I did not appreciate just how much of this fine dust was being produced.

Have fun!

John

I have a new plan / thought /idea for my situation. It is still based around:
- minimal noise (at least eventually)
- magic numbers
- venting outside (eventually)

This is based on me already having a 'woodshed' which is only 1.8 to 2metres tall but would be ideal to house the DC externally

1. Buy something like MWE-DU05 Dust Unit - Major Woodworking Equipment which is a 5hp 3-phase standard DC on wheels (with a decent design). I'll need to find one that can run on 240volts as that is all I have. To do this , I then need a 15-amp GPO and a VFD. In the short term, I will use this as a portable DC. I will need a sparky (my brother is one so hopefully I'll bribe him to come and visit) but I should be able to get this up and running pretty quickly. Depending on how quickly I can get number 2 done below, I might even get pleated filters but this seems a bit of a waste if it is only for a short time.

One question on this. As I would be using a VFD I assume I can bring the hz below 50 to reduce noise, although with an accompanying reduction in 'flow'. Have I got this right?

2. What I call the building phase. My preference would be to put a CV (or other BP spec) cyclone only inside my big shed and the DC (with filters removed) in the woodshed and have it fully ducted. I could even start with building hoods / modifications for my lathe and bandsaw (most used tools) and attach the portable to these. Another option would be to find some short pleated filters for the DC so I can fit the whole thing in my woodshed but the cyclone is my preference.

A question for you cyclone users - my understanding is that most of the noise is from the venting, then the motor being second so I don't expect (perhaps wishful thinking) that the introduction of the cyclone in the main shed will add significant noise. Does this sound right?

As always, I am happy for crtitcisms and comments. I would even accept a positive comment

thanks

Mick

Mick mate there is no free lunch.....why would you buy a 5 Hp 3 phase motor only to knobble it, to fit into a 15 amp single phase supply.....it just does not make sence.

You would be better off buying a 3 hp single phase unit...and save money on both the blower and not buy the VFD.

cheers

Originally Posted by soundman

Mick mate there is no free lunch.....why would you buy a 5 Hp 3 phase motor only to knobble it, to fit into a 15 amp single phase supply.....it just does not make sence.

You would be better off buying a 3 hp single phase unit...and save money on both the blower and not buy the VFD.

cheers

If I can find a 3hp that I think will do the job well enough this is still definitely an alternative. I thought the 5hp seemed hardly any dearer and with a VFD I could run it with less 'oomph' when needed (I still don't know how this relates to power and cost and am hoping to find out via this forum ) but it would give me more options down the track in potentially having more than one machine running at a time and /or long lengths of ducting.

Also remember, it was only Plan / thought/ idea number 27.2 revision 4

cheers

Mick

Hi mick59wests.

I understand your concerns in choosing the right dust extraction system for your shed. Never easy to make a decision when there are many options and conflicting views.

I have a few observations from years of running a wood workshop that you might consider.

Firstly after working in a workshop without any dust collection then with a Jet "2Hp 1200cfm" dust extractor firstly with a felt top bag then replaced with a Jet pleated filter, I have now ended up with severe respiratory problems that require me to put in an effective Dust collector or give up woodworking.

Personally I could never recommend a Dust Collector no matter what the size because most of the dust collected ends up not in the lower bag, but in the filter, which blocks the airflow. The Jet pleated filter has flappers which you rotate to dislodge the dust into the lower bag hopefully done at least once a day. Unfortunately these are only marginally effective and I always ended up having to remove the filter to clean it out. The dust collects and packs between the pleats and is only partly removed by the flappers. Result dust all over the shop and me. Sort of defeats the purpose. The problem is particularly severe if you cut a lot of material such as MDF which produces masses of fine dust.

Secondly be wary of manufactures airfow data. My Jet 2Hp 1200 rated at 1200 CFM with a used but a fully cleaned pleated filter would not extract greater than 760 CFM with a 1m length of 150mm inlet duct. This was an actual measurement made with a Pitot tube and Dwyer Digital manometer. To get the 1200CFM flow I believe you would need to remove the inlet and outlet ducts. The connection between the fan and the filter seems to be the significant restriction.

I am in the process of installing a CV1800 with 150mm ducting all the way to all my machines. Sure it will be noisy, its relatively expensive and I will have to add some sound proofing but in my book my health comes first.

My only regret so far is that I did not buy the CV max and run it at 50 rather than 60Hz.
I understand that his would give equivalent air flow to the CV1800 but at lower noise level.

Cheers
Ron

Originally Posted by mick59wests

I have a new plan / thought /idea for my situation. It is still based around:
- minimal noise (at least eventually)
- magic numbers
- venting outside (eventually)

One question on this. As I would be using a VFD I assume I can bring the hz below 50 to reduce noise, although with an accompanying reduction in 'flow'. Have I got this right? Yes, You can bring the motor below 50 hz 10 is about the lowest and yes lower flow.

Another option would be to find some short pleated filters for the DC so I can fit the whole thing in my woodshed but the cyclone is my preference. As Ron says below pleated filters block up and the paddles only clean so much, the rest of the filter just blocks up, to clean they have to be removed and brushed or blown (air comp) and that's a whole lot of dust and mess

A question for you cyclone users - my understanding is that most of the noise is from the venting, then the motor being second so I don't expect (perhaps wishful thinking) that the introduction of the cyclone in the main shed will add significant noise. Does this sound right? I made my own cyclone as per BP, the cyclone itself doesn't make any real noise, most of the noise is from the exhaust. I made a muffler for the exhaust which did reduce the exhaust noise, don't have any before or after numbers, the fan housing is the next, the amount of noise is a function of fan design, speed of rotation and the interaction the fan has with the housing, e.g. How close is the fan wheel to the fan housing, there are engineering solutions here to reduce this noise. I did enclose the fan housing and motor using some freezer panel

As always, I am happy for crtitcisms and comments. I would even accept a positive comment

thanks

Mick

For my money a cyclone with a 4hp motor(min) completely outside or vented to outside, 6"min 8"max mainline ducting with collection points on machines to suit is a good solution, I have worked without any dust collection and with hoses on the floor, one time I was stepping over and got tangled up, very nearly went A up. I am very happy with the my cyclone and system, no more moving hoses




Pete