Extraction advice needed!!!!!!

[cumbrian]

Not sure if this belongs here or in the Buying Advice forum, so apologies if I’ve got it wrong!

I realise that I need some extraction, but I am totally confused by what is available and what would best suit my needs, be it one extractor or two. I’ve had a search through previous postings, and I even followed the link to the Bill Pentz website, which left me with the belief that if he’s right then most of the contributors to the forum must in fact be dead, which raises some interesting questions about internet access from the Spirit World....
:shock:

So can somebody please give me some simple advice on what I need? Here’s the scenario:
I’m new into this game (standard get-out clause for stupid questions), and I’ve got a few second hand machines I’ll be putting to a fair bit of use soon. I’m not currently in a position to have a dedicated workshop, so plumbed in extraction is out. I therefore need something mobile(ish) for the tools I’ll be using, which are an old DeWalt P/T, which has no dedicated extraction outlet, an old Startrite 352 Bandsaw, again no outlet, a SCMS (and maybe a RAS) and a handheld CS. It’s likely that I’ll be sawing some MDF for carcass work, unless I stick with ply.

I’m impressed with the opinions given on the Trend Airshield and I’m likely to buy one, so what else do I need? My understanding so far suggests that the requirements for the P/T and the saws are very different – is that right, and does that mean two different extractors? If so, it seems that the airborne dust from the saws is the important issue to address first; I can handle the shavings from the P/T with a dustpan and brush for now – or does the P/T merit dust extraction as well? And how do I go about getting efficient extraction from the bandsaw?

This may be a very basic question, but without this forum I wouldn't even have known to ask it! Any advice, and suggestions for specific equipment, would be very gratefully received!!

 

[Pecker]

Right, Lets be pratical here, rather then pedantic and picky. Space is of an issue- so one machine must do all, and I guess budget is too.

MDF dust IS a real risk even in small quantities so if possible we need to look at something that has fine filtration.
P/T s throw up a lot of bigger shavings, so the size of collection sack/bin is important thaen the siz of filtration level.

So, we need a reasonabe bin size with idealy 0.5 micron filtering.

Something like the Camvac or Record range would seem to fit the bill. They both filter down to 0.5 micron for the bad stuff, but both come in various sizes of bin or sack collection.

If you could, I would suggest one fo the larger of either of those two makes as it wouldn't fill up every two mins when planing, but also filters the mdf stuff down enough.

The bandsaw... I once had the same problem, so i managed to cut a hole in the bottom casing and attched a 2.5" outlet which worked really well, for minimal cost.

I've just realised something. There should be a "hood" type extractor cover that fits over or under the P/T, if you havnt got one, it would be well worth trying to obtain one as the amount of mess these things make is horrendous.

One other point, many people on here like these air filters that you leave on for a couple of hours, and they halp "suck" some of the finer dust out of the air, which certainly wouldn't be a bad thing at all.

Hope this helps,
mark

 

[Barry Burgess]

The Trend airshield is only a start but better than nothing (I have one). If you are going to build hoods for your equipment try to make them at least 4" for the SCMS and TS etc. For your hand tools a 1 1/4(32mm) or 2"(50mm) attached to a vacuum with filters and some form of dust bucket The SCMS is one of the most difficult to catch the dust from. The bandsaw is easy - you cut a 4" inlet and use one of the plastic hoods from Axminster or Charwood . The problem for you is with hand tools the vacuum is king but with the larger tools you need more airflow. If you believe Bill P only 6" will do - but this is American standard!!! You can get away with a Camvac - the 4" is better or build a cyclone and pipe the whole workshop at the other extreme.
I started out with a vacuum and then build a dust bucket and then a cyclone or two for the vacuum that I still use. When it got to the position where I was about to buy a third vacuum - I bought a standard dust extractor and found it was the biggest producer of dust through the bag system. Was totally Pis*** off and went the cyclone route. The choice is yours - start small and only advance if you feel the dust is not doing you any good - then improve you collection system.
I found that going to gym after a day in the workshop got me going.
Start small and see
Barry

 

[Colin C]

If you have the Dewalt version of my Elu P/T then you can get your hood Here as I have to get one too

 

[engineer one]

i think the most important thing is to make sure you have a proper mask,
and the trend is probably the way to go.

as for extraction, for sheet goods you need different from "real wood"
and some recent suggestions are that trying to avoid having mdf dust
hanging around, so in some ways the overhead machines are not much use unless you leave the shop.

if you are making shavings, then they do not stick in the air, whilst dust
does, so on the table saw, and an scms, you need extraction with
a cyclone to get most of it to stick. having seen barry's stuff i know this to be true in the same way that i know that most pentz stuff is hot air,
(sorry ) and rather like some global warming words based on unclear data.

whilst the camvac and other extractors seem good in the first instance,
you need something that will direct the input air away from the filters,
and put the chippings in a dust bucket before the air goes back tothe
filter. interestingly, you need pretty high pressure to pickup the chippings
and dust, but the exhaust through the filters should be quite "soft" or low
pressure to ensure that you do not blow the dust through the filter.

finally the thing to think about is how easy it is to remove the dust collecting receptical once it is full. so many of these let more dust go when you release the clips than they seem to collect. i have a trend vacuum which is pretty good, but i do need to be careful when i empty it, there is a big lip at the top.

so the answer is a compromise.

use a decent face mask, and then decide which tools are going to produce the most dust, like mdf and be careful there, so an adapted cyclone is the way to go, whereas a camvac or the trend could be valueable for actual chippings.. :roll: :?
paul :wink:

 

[Pecker]

I'm sorry, I'm going to put the cat amongst the pidgeons here as a pro woodworker of 30 year experience.

I think most of Bill Pentz's stuff is unproved discredtited scaremongering. On a recent american site he woudn't even respond to cristism or agree to publish facts and data he insited be made available by other competitors relating to his own machines. He is a one man band that doesn't seem to have one single ally in the whole commercial world. If he was THAT good, every other manufacturer would have taken his workings and created their own versions.

If you look at a Camvac (for example) they have three filters, two cloth, one paper down to .5 micron. They would be hammered by various legal processes if their product didn't do what they claim it will - and whilst not being a fan of theirs, their stuff works VERY well, I have one.

The cost of building a cyclone and the ancillary pipework due to limited space is not availabe to the original poster.

I do not doubt that cyclones are good and work well. I do doubt dubious totally unbacked up claims that say every other machine in the whole world ever invented to suck up wooddust don't work and are dangerous for your health unles you buy one of Bills own machines.

ANY machine is better than none, and nowadays with litigation at the forefront, NO manufacturer is going to make claims about the capabilities of their machines, unless they are dead certain of their facts.

For the average hobbyist, the amount of harmful dust one would breathe in over the course of a year with a reasonable system is extremly small. Even in a pro workshop within a large NHS trust hospital using a 30 year old system, used by 5 carpenters, our own air tests were excellent. Thats not to say they couldn't be better, nor am I saying dust should be ignored.

But any modern well filtered system, especially if used in conjunction with a face mask for MDF should be quite enough for most people. Furthermore, Whilst I am not a fan of suspended air filters, if they do remove airbourne dust, that too must be a good thing, rather then letting it all stay in the air for hours. only to fall down and be disturbed next time somebody moves anything in the workshop.

Not everybody has the room, can afford to build or can be bothered to read dozens of pages of contradictory informatiom then build a cylone. Therfore a good quality readily available machine should more than suffice.

Edit: just to say I am not taking pop shots at any individuals here, or their own experinces with cyclones. That is not the point of this posting so please do not take it personally if you have built a cyclone - I am not out to offend you.!!!

mark

 

[gardenshed]

No offfence, but IMHO that's a lot of nonsense :roll:

what's 30 years in reality, you could learn not much in that time or a lot.
some people could learn a lot in 30 days or 30 months.
It doesn't mean you know more than anyone else on this forum, just because you claim to be a 30yr pro woodworker. That means nothing to me,

With the greatest respect if you think the Pentz site is unproved uncredited scaremongering, then anyone can think any of your posts is uncredited, unproved rubbish.

I don't know Bill Pentz, I've read some info on his web site, some of it is good info, some of it is over my head, but the more people that become aware of wood dust the better imho.

I also know factually that unfortunately he's not in the best of health these days and that he's very highly regarded on various woodworking forums.

If you think other peoples information is as you claim in your post, then prove it, tell us why it's scaremongering, give us the facts, give us the information so that it can be evaluated so we can decide whats good information and whats bad.

I'm sorry, I'm going to put the cat amongst the pidgeons

mark

Methinks it's time to keep the cat indoors as the pigeons might come home to roost...

 

[Pecker]

My professional experience spans 28 years, I hold adv C&G in carpentry and joinery, and Hnd in Building Sciences. I have stated several times within these forums of previous work placemants and experiences including the NHS in Southampton I also run my own business and and not going to go over them as it's pointless.

I would willing like to point you to a large american forum that about three weeks ago had a raging debate over Bill, unfortunetly I cannot find the link, but I'm sure someone will come along and supply it. It was withdrawn amid cries of censorship after a competitor challanged Bills claims and bill couldnt'/would answer at first saying he wasn't aware of the posting, then saying he was out of town at a friends testing a meter, then saying his lawyer was closed, yet the forum own mods stated he had been visting the site only that day.

Bill's claims are VERY contraversal and just like you, he has ignored the fact that NOT ONE single commercial producer has taken on board his designs. Furthermore even members of this very forum will tell you that some of his maths don't quite add up.

To accuse me of scaremongering and attacking me personally is rather poor. I have not scaremongered at all and meerly pointed out that there are TONS AND TONS of contradictory arguments, just bother to do some basic searching and they are not hard to find. Indeed it could be argued that it is Bill himself who has scaremongered by insisting that the ONLY way forward is HIS cyclone. Read his writings yourself, they are full of scary "facts" susposedly said by an unknown doctor who seems to know more about air filtration then any corperation in america or the rest of the world.
Furthermore you ask for the proof of other people writing these things, why dont you just do a search on THIS forum. Since you attack me personally and accuse me of writing drivel, it is obvious you havent even bothered to look at previous postings on here, other forums or even Bills own site. so I'll be darned if I'm going to do it for you, when many peope on here know this subject too well.

mark

 

[Jake]

whilst the camvac and other extractors seem good in the first instance,
you need something that will direct the input air away from the filters,
and put the chippings in a dust bucket before the air goes back tothe
filter.

Why? Mine works fine without any of that.

interestingly, you need pretty high pressure to pickup the chippings
and dust, but the exhaust through the filters should be quite "soft" or low
pressure to ensure that you do not blow the dust through the filter.

I've seen the dust trapped on the outside of my camvac's second level filter and it's bloody fine - the finest dust I've ever seen. To get blown right through it would have to actually get through the pores of that paper bag, and then through filter number three. And then would knacker the motor so would lead to a whole bunch of warranty claims.

If there's a criticism of the camvac approach it can only be based on total throughput, imho, not the effectiveness of the filters which is light years ahead of standard extractors and as good as any cartridge filter which wouldn't strangle a low pressure fan.

finally the thing to think about is how easy it is to remove the dust collecting receptical once it is full. so many of these let more dust go when you release the clips than they seem to collect. i have a trend vacuum which is pretty good, but i do need to be careful when i empty it, there is a big lip at the top.[quote/]

The top comes off but the main filter stays in place, the only dust spillage that is possible really comes from detaching the hose.

 

[engineer one]

jake i am sure that we all agree camvac do a decent job, but part of the whole thing is not the dust you see but that you really don't.

i found with the trend that by moving the airflow away from a direct entry into the filter, the filter took longer to block up. that's personal experience.

looking at some of the american magazine research, and indeed thinking back to some of my engineering experience with filtering for motors, any device that can reduce the amount of filtrates going on to the filter is going to stop the filter blocking up. one of the things that comes up with much of the published work that is based on proper testing, not empirical work,
is that filters improve their performance when they are partially blocked,
but there is a fine line between good performance and drop off.

a piece in popular woodworking in 2001 by the guy who got moved off the recent american forum, reminds everyone that 99% collection at source from the machine is better than collecting it from the air. to my mind we are always going to be fighting a losing battle until manufacturers take extraction more seriously. the scms is perhaps the worst culprit, then after that the table saw is a difficult machine to completely control, and finally the router. other machines offer better chances of directing 70-95% of the waste products into a decent collector.

the problem to most right thinking people is that when put to the test much of the pentz formula is not correct, and frankly totally unsuitable for the uk market anyway due to size and space problems over here. barry has built a cyclone to the pentz formula and it does not work as well as the bodge up in the smaller sizes. i know i saw it.

i agree that at this time, and over here, the cyclone is quite an expensive solution, but also know that even camvac do not claim to be the whole answer.

what intregues me is that you can buy a centralised vacuum system to be fitted or retrofitted into a house, and have been able to do so for many decades, yet no one seems to have adapted that for the dust extraction of a woodshop, why???

this is getting a bit disjointed, so sorry, and i am still sober :roll:
but i now tend to think of mr pentz as a woodworking equivalent of
rosemary connely the women who produced the low fat diet. once you have promoted a certain product that seems to promise and for some deliver a miracle, it is difficult for contra views to be heard.

i know that my answers are not the only ones, but it is based on actual experience of both systems, and reading properly researched magazine articles which have some science to them.

paul :wink:

 

[gardenshed]

To accuse me of scaremongering and attacking me personally is rather poor.

mark

I didn't, I said "then anyone can think any of your posts is uncredited, unproved rubbish." And incidentally aren't you attacking someone???.

Someone who's not on this forum to defend themselves by the way. I think that's rather poor imho.

My professional experience spans 28 years, I hold adv C&G in carpentry and joinery, and Hnd in Building Sciences. I have stated several times within these forums of previous work placemants and experiences including the NHS in Southampton I also run my own business and and not going to go over them as it's pointless. mark

That's My point entirely, it was pointless.

Since you attack me personally and accuse me of writing drivel,mark

But isn't that what you are saying about someone else's writing?? and what's this word "attack"" I was being critical of your post being critical of someones web site info. I don't see any personal "Attack" in my post, critical yes but no "Attack", if there is I apologise unreservedly.

Furthermore you ask for the proof of other people writing these things, why dont you just do a search on THIS forum. it is obvious you havent even bothered to look at previous postings on here, other forums or even Bills own site. so I'll be darned if I'm going to do it for you,mark

I have bothered to read the info on this & other forums , I've read an awful lot about the subject. I just ask You to prove your comments in your post.

I shall not reply to any other posts on this thread as I can quite clearly see it getting out of perspective from the original post. I'll agree to disagree.

 

[engineer one]

it is always interesting to see that when people make personal attacks
they then run off into the distance, they then justify themselves by
saying that they do not want to go off topic.

dust extraction is like global warning, and much of the science is as dubious. what makes the work of mr pentz dubious is his use of mathematical formulae without understanding. why should the ratio of height and diameter be the "golden ratio" for convenience, not proper science.

don't just knock someone who has knowledge, and offers their advice whilst questioning the fact that one person has gained a reputation as being so pedantic about their work being the only answer to a problem.

there are many different approaches to extraction, and no one approach is correct for all circumstances, and just because you say it is so often enough does not make it right.

one of the major problems with a cyclonic system is that it is space hungry
but then some of the twin filter systems take up a lot of room too. those picture in the axminster catalogue show some really large systems from sheppach, axminster themselves and others, so one argument is out the window.

however what is important to understand is that you need to separate the chips from the dust, and then stop the dust getting back out into the workshop. many filters are designed to draw air through them for other uses like on a car, whereas the filters on extraction are designed to draw the dirty air in and stop it before it gets to the motor, as well as making the exhaust as clean as possible. there are a number of ways to do this process, and the camvac system seeks to do it by making the air go through two or three filters, oneof which is a sack.

in my practical experience the cyclone removes the need for many of the filters and extends their life. however i am pragmatic enough to know that others may well disagree with me about my conclusions, but it does not make my views any less valuable.

to the original poster. you need a mask whatever, then think about point collection, and then plan about the materials you are going to use. as i have said before, if you are using sheet materials then the extraction is really much more important especially since you are more likely to use machines to produce the final product, but i ask how do you stop the dust when you use a cordless drill for holes?? i have yet to find an answer to that. secondary extraction is to start with something like the trend vac, or a camvac, and then when you are doing more work, then you can move on.

the precautions are worthwhile, but rather like learning to sharpen, take time to decide what is right for you. :twisted:

paul :wink:

 

[Lee Brubaker]

Oh my, the posts here remind me of some of the American forums I have visited over time & some of them no longer exist or I no longer visit them. I'm 75 years old. I'm not a professional of any sort hence, I never feel someone is threatening my knowledge or pride.
I'm what I call a hobbyist & have in the past posted pics of some of my work here. I have a small shop & in it I have squeezed a American Machine & Foundry made DeWalt RAS with 1hp & 9" blade which I bought new in 1958, a lathe bought when I was 14 yrs old with paper delivery money, a 1hp router which I mount on my RAS, a router table with a dedicated 3-1/4hp plunge router, a horizontal router table which I mount a Makita 3-1/4hp plunge router also used as a handheld router, a 3rd 3-1/4hp router that mounts a circle cutting jig as a base plate(I make wooden animated toys which are distributed to needy families with children at Xmas), a 13" thickness planer, a 6" jointer, a CMS , a down draft sanding table, a 14" BS with riser kit, plus various hand tools.
What do I do about dust ? Really high tech I assure you.....a so called
6hp shop vacuum piped to each machine with blast gates & flexible 2-1/4" hose to each machine. I use a after market pleated filter(.5 microns)in the vacuum over which I stretch one of my wife's panty hose to prevent the fines from plugging the pleats. I use a cheap remote switch to turn the vacuum on & off. I have a spare filter on hand so that Iam not unduly interrupted when I notice the vacuum efficiency falling off. A quich change-out & I'm back in business.
Of all of the machines, I find the BS to be the dirtiest which I could improve were I to cut a port in the bottom wheel housing instead of the port under the table at the lower blade support.
So.....you can get by with a shop vac. It aint perfect....but it does work if a little common sense is applied.
As to MDF. That & cedar are two very serious dust generators. Breathing apparatus's should ALWAYS be used when working these components.
MDF is especially bad in that not only copious quantities of dust results from machining, but it is also very fine & impregnated with adhesive & can produce a similar lung condition to coal miners black lung.
So there you have it.....my 2 cents.

Lee

 

[Barry Burgess]

I don't care what you use to separate the dust from getting to the filters but you must agree that dust (mainly fine dust) drops the efficiency of the filter. In most commercially available systems today the filters are too small and the micron claims of most are not up to standard and as woodworkers of all descriptions we are unable to verify these claims.
Having built 3 different types of dust bucket and 4 different types of cyclones none are perfect but most are better than nothing at separating the dust from the air. Collection at source should be the aim of all woodworkers as once it enters the air the problems start. Just check your workshop the day after 3 to 4 hours of cutting etc. If you have no settled dust you have the perfect solution - please let me know how you do it - I am still trying.
The slanging match on the American site is not about is the cyclone the way to go buts who's cyclone and filters work best and how do you measure the results It is more than likely that neither Oneida or CleaVue are totally right as it depends on the machines in your workshop and the layout. Just by opening the garage door and windows on the opposite side if you have them greatly helps the situation . My Aussie mate has a roller door at each end of this workshop and the prevailing wind does the rest but they have the weather for it.

 

[Pecker]

There can be no doubt that Bill Pentz has done more to raise the issue of dust collection and the harm that it can cause, then just about any other person in the woodworking arena. For that he deserves much credit, as he does for the amount of time and effort he has put into trying to improve the situation for hobbyists. (One minor point, Bill suggests commercial/pro extractors eject dust into the air outside. I'd just like to note that having just had an environmental inspection carried out by Arena Networks, that is now VERY carefully controlled, and indeed in this present climate is discouraged and heavy fines can now be levied.

However The basis point I was making was that just about any commercially built unit is better then none, and some machines really do seem to work very well. My old Camvac I aquired during the takeover of my premises is badged AEG,is 17 years old, has triple filtration, and really is very good - even if I also think the airflow rate and bin capacity is small, and that a cyclone is not necessarily the only way forward.

mark

 

[Jake]

jake i am sure that we all agree camvac do a decent job, but part of the whole thing is not the dust you see but that you really don't.

Yes I know, I am familiar with this debate. I didn't mean individual particles, I meant the little 'drifts' of millions of particles which I can see, each of which particles would be too fine to see on its own (except in a beam of light). The (small amount) of stuff that collects on the outside of the paper filter feels and looks to me as fine as fine soot.

i found with the trend that by moving the airflow away from a direct entry into the filter, the filter took longer to block up. that's personal experience.

I think that is axiomatic, the real question is to what degree that clogging affects the throughput. With a little vacuum like the numatic I used to use, and to a lesser degree my CT44, you can sense when the filters are clogging up by a slight change in motor tone and/or lesser thoughput. I honestly can't say the same for the camvac, it has just so much more brute force.

 

[Jake]

i agree that at this time, and over here, the cyclone is quite an expensive solution, but also know that even camvac do not claim to be the whole answer.

Oh quite, the camvac is hardly a cheap solution itself. Nor is it the ultimate be all and end all to have inthe workshop of one's dreams - it is a small time convenient compromise solution. I just wish people wouldn't say 'oh its ok for chippings but not fine dust' when it is much much better at fine dust than your bog standard dust circulator, and has a level of filtration that ranks with the best.

As I said, the real questionmark for me is over its throughput. If you take Pentz's 800cfm as the benchmark - which Pentz says dictates a 6" pipe system, including all new hoods, etc - then even the big camvac clearly falls well short. If, that is, you accept that Pentz is right in everyhting he says and that 800cfm is an absolute requirement.

i now tend to think of mr pentz as a woodworking equivalent of
rosemary connely the women who produced the low fat diet. once you have promoted a certain product that seems to promise and for some deliver a miracle, it is difficult for contra views to be heard.

I share similar views. For start, his whole approach is based on low pressure systems, and some of his arch proponents cannot seem to wrap their minds around the fact that that means that many of his calculations cannot directly be applied to high pressure systems (and the workings of his calculations are not shown, so you can't adapt them). More generally, something about his pages that irritated me a little when I spent a great deal of time reading them a couple of years ago, and again in the debates a few months ago, which is that when you look at the underlying fundamentals of what he says, there is actually a lot of assertion and not that much explanation.

 

[engineer one]

as usual jake we don't come from the same direction, but have the same basic view. none of the systems are perfect, and we should all try to achieve the best for our own circumstances.

let's look at what we do know.

1/ ALL dust is bad in certain accumulations
2/ all the processes we use produce some amounts of dust or chippings
3/ the best practice is to try and capture as much "waste" as possible at the place of production. whether by hand or machine work.
4/ recognise that hand work does produce less fine dust, but some of the "real woods" that we use produce dangerous by products.
5/ it is easy to get carried away by listening to the various panic pronouncements of various "so called" experts. the number of people who claim that mdf is banned in america is legion, yet every month the magazines suggest another use for it.
6/ we must laud mr pentz for bringing to the notice of every one that dust is dangerous, and that we should use our best endeavours to reduce it.
what we cannot do is take as holy writ the pronouncements of one lone voice who in recent times seems to have accepted more and more corporate sponsorship, such that his views seem less and less honest and more and more about protecting his perceived reputation.
7/ different machines need different throughput of air, and one size cannot fit all.
8/ very few machines have proper dust extraction built in. a couple that i know of that work very well are the surprising ones, many random orbit sanders, like my bosch 150, and the festo seem very effective, but most table saws, band saws and scms are blo*dy awful.
9/ take the table saw, you need one kind of air at the top of the fence, and another underneath and in the middle there is a strange vortex of air which really messes up air flow. so even in one machine it is not easy.
10/ any thing you do is better than nothing, and watching tommy walsh in the open using a stone grinder with no mask is not a relevant excuse.
11/ there are others in our lives, and they too may well be exposed to the effects of our dust production, so we need think about as much long term reduction as possible.

long winded again i know, but this subject really does get many people over the top. so we have to stand back and look more carefully at our approach and what we defend, even if the science is dubious.

a/ one size does not fit all
b/ to my understanding, almost all the filters on offer are inlet manifold filters not exhaust, and maybe the science is not all it could be there.
c/ by developing clean habits we can reduce the long term risks.
d/ we need to keep talking to each other in a polite and civil way even when we disagree.
e/ did i do the line typing right jake :lol: :twisted: :roll:

paul :wink:

 

[Jake]

e/ yes thank you very much, I find it much easier to read!

 

[engineer one]

touche :twisted: :roll: :lol:

paul :wink: