Dust Extraction

[Scrit]

Personally.... I'd LOVE to see manufacturers get their act together about this. Surely THEY know how much mess their machinery can generate....

Possibly - but not if they are Italian (are you listening Biesse?)

a label on a chip extractor giving the max size of planer it can handle waste from.... with 100% efficiency.... "Not suitable for planers above 200mm"....... it's not rocket science...

Well, not exactly, but there is a bit of maths involved. The problem is that for dust extraction you are really talking about a system - NOT a machine - so a label such as you are discussing would be totally meaningless. Different chip hoods have different characteristics and efficiencies. The same goes for pipework systems. That's why I recommended one of the few books available and pointed you to Bill Pentz's site.

Surely that increase in units sold would soon bring the cost of these more expencive systems down.

I don't think so. WW dust extractors are pretty much bargain prices anyway and in any case the DX guys regard the poor WWer as a cheapskate and a pauper because we (both amateur and professional) only spend money when we are forced into it, and then less than is really needed to provide a proper solution (what I've been told).

We do suffer from the problem of buying (or being sold), and generally by someone little less ignorant of the facts than ourselves (pronounced "machinery dealer"), an extractor without properly investigating what we are going to do with it. This is putting the cart before the horse. What we should do is write down our requirements, design a system THEN buy the parts needed (including the extractor).

DX is a bit of a 'black art' with relatively little published, apart from the book I quoted and Bill Pentz's site (see both links above) and the Felder catalogue, the only other sources I know of are the Woodstock Intl book "Dust Collection Basics" which you'd have to order from the States (not available here), although it is only a fiver or so (Woodstock ref. W1050, ISBN 0-9635821-2-7) and the Oneida Air web site
http://www.oneida-air.com/

Charley - maybe this should form the basis of an article?

Scrit

 

[Noel]

In addition to Sandor Nagyszalanczys' "Woodshop Dust Control" another excellent book on dust collection is by Rick Peters and available from Amazon UK at:
http://www.amazon.co.uk/exec/obidos/ASI ... 41-0623651

Another Nagyszalanczy book with a more general look at dust management is his "Setting Up Shop", also available from Amazon UK.
All three books highly recomended.

Rgds

Noell

 

[Anonymous]

Ok, after reading all that advice anyone know where I can purchase some flexible ( pvc preferably) 100mm hose with a smooth interior?

 

[Scrit]

I'd start with Senior Hargreaves in Bury, Lancashire (Tel. 0161-764 5082), but Axminster also sell it as do Felder

Scritb

 

[Alf]

Another Nagyszalanczy book with a more general look at dust management is his "Setting Up Shop", also available from Amazon UK.

Good call, Noel. It dawned on me last night that I've just got "Setting Up Shop", and I started to look a bit more closely at the dust extraction bit. When I read it before I skipped that bit to get to the pretty pictures of workshops...

Mike's idea of using a system so we'd know what any given d/e was suitable for seems such an obvious thing to do, but Scrit's explanation of why it couldn't be done seems to be pretty obvious too. (Once it's pointed out to you...) I can't help thinking that dust extraction will continue to be an afterthought/under-budgeted for, until buying the blooming things has been simplified a lot more.

Sorry for the moan, but when you try and do the "right thing" to protect your lungs, and it isn't the right thing after all, you get a bit disheartened. And not a little broke!

Cheers, Alf

 

[Noel]

Alf,

Totally agree with you that dust and chip collection will remain on the sidelines. We all know how important it is to have a clean and safe workshop but with such a wide choice of equipment and standards it can get very confusing for the layperson.

Ref your comment on flicking through WW books to get to the "Tool ****", I think most of us are "Tool Junkies" at the end of the day. (hope no offense caused with above terms...)

Rgds

Noel

 

[Anonymous]

I'd start with Senior Hargreaves in Bury, Lancashire (Tel. 0161-764 5082), but Axminster also sell it as do Felder

I rang axminster and they said their flexible hose is not smooth inside.

Considering that and that their flexible hose is £8.88 and £13.25 a metre, if I cannot get a smooth bore inside I think the aluminum 4" expandable venting tube from Wickes is a much better idea, not least because its £5.99 for a 4 metre ( once expanded) piece :shock:

I cannot see why it won't do @ least as good a job as the axminster stuff and at least £7.00 a meter cheaper, very welcome

 

[Signal]

Billzee,

be very careful with the ducting from wickes and others
I tryed to use this one and it just collapsed as soon as I turned
on the dust ex.

Cheers

Signal

 

[Anonymous]

Thanks signal It was just an idea

 

[Signal]

Billzee,

quite allright, hate for someone else to end up with soiled undies like
I did. When it collapsed it went with a bang :shock:


Signal

 

[Midnight]

Well, not exactly, but there is a bit of maths involved. The problem is that for dust extraction you are really talking about a system - NOT a machine - so a label such as you are discussing would be totally meaningless.

Scrit..
OK....... so a compatability label wouldn't work.... gotta warn you... I'm not letting go of this label idea yet.. :wink: how about..... on every mess generating machine... a label endorsed by the British Standards Institute (remember them...?) giving the required CFM needed to make the machine comply with the new dust collecting regs due to become law in December. The BSI label would guarantee that the machine had been tested under "real" conditions.... cfm measured at the machine end of the duct..... NOT the extractor end with all the filters n hoses removed.

As for a DC system, not all of us have the luxuary of having the shop space to have machines permanently set up, much less hard piped into a ducted system. By the time I get my extractor hooked directly to either the planer....jointer or router table, I gotta suck in and walk sideways to move in my shop.... keeping a large collection system in there permanently would be a nightmare.

Earlier tonight I was browsing Rexon's site, looking at both the extractors listed there... 500 and 750 watt collectors... both with the same rated air flow. It didn;t take long to figure the limiting factor was the 4" hose. Like Bill's site says.... the minimum size duct to use for maximum blockage free flow is 6"......
As I recall..... te only catalogue I've seen ofering a 6"+ outlet extractor with a 2000+cfm rating was Axminster.

 

[Anonymous]

Ive come to the conclusion that if space and funds are finite this whole idea of a complete workshop is pie in the sky.

One should forget the idea of processing timber from sawn, rather find a good yard where you can take a cutting list and let them do it. Concentrate your funds on a few quality machines and a high quality hand tool set.

If I knew then what I know now that would have been my way

 

[Scrit]

For dust extraction where you are working under a vacuum you need somethink more substantial the HVAC pipework. Even the metal ductwork will collapse under the vacuum imposed by a dust extractor. If you really want a cheap alternative take a look at the 100mm soil pipe sold by plumbing places. This stuff can be glued together and is strong enough to stand being buried, so it won't collapse under vacuum.

Billzee - why do you want the really smooth bore flexible trunking? The smoothest stuff I've seen comes from a DX specialist in Bradford. It is really heavy duty and "puncture proof" (doesn't stop it wearing out, though) and we use it on our CNC - but the 125mm diameter stuff costs around £35/metre - aghh!!

Mike - I agree that some form of extraction figure would be useful for the machines. Industrial machine manufacturers already supply this information - pity is that it is normally hopelessly inaccurate, which is why the DX companies tend to have their own tables for machines.

Glad to see you've looked at Bill Pentz's site, but there are lower cost alternatives than going to a 2000cfm unit or one of Bill's cyclones, such as fitting a better impeller (take a look at the Oneida Air site I quoted above to see what I mean) or welding vane extensions onto your existing impeller plate (I had a link for this, but I can't find it, if I do I'll post it). Part of the trick with the Oneida uprades is that they open out the baffle/inlet plate on the DX from 4in to 6in. Another thing to try is replacing the filter sock on your chip collector with a better-quality 2-micron (or less) bag from a reputable manufacturer. A good filter sock reduces the back pressure on the chip collector and the flow rate increases, providing that you've got large-enough pipework.

BTW, which piece of regulatory wizzardry is due in December (apart from the first part of PUWER 98 on static WW machines)? I thought the relevant stuff was ATEX which came in earlier this year. Have I missed sommat?

Scrit

 

[Midnight]

BTW, which piece of regulatory wizzardry is due in December (apart from the first part of PUWER 98 on static WW machines)? I thought the relevant stuff was ATEX which came in earlier this year. Have I missed sommat?

The 5 year grace period that PUWER 98 had ends this December.

 

[Scrit]

[/i]The 5 year grace period that PUWER 98 had ends this December.[/i]

Yes, for some machines like circular saws, band saws, radial arm saws and tenoners with saw blade units (the so-called "high risk" machines), this is true. For others the dates are between 2003 and 2008 depending on the type of machine, although most remaining WW machinery falls due in 2005. See the HSE Woodworking Sheet #38 (page 3) for the relevant details http://www.hse.gov.uk/pubns/wis38.pdf. The relevant braking requirements are laid down in yet another piece of legislation, ACoP (the Approved Code of Practice).

PUWER does not refer to dust extraction in any way. There is some very relevant stuff on the HSE site about dust extraction (the LEV or Local Exhaust Ventilation notes). Take a look at this web page, it may help in the design of your own dust hoods http://www.hse.gov.uk/pubns/wis23.htm. For saws the following link will be useful http://www.hse.gov.uk/pubns/wis24.pdf, for belt sanders this one http://www.hse.gov.uk/pubns/wis25.htm and for drum and disc sanders this one http://www.hse.gov.uk/pubns/wis26.htm. Don't ignore these simply because they are HSE advice, there is a lot of useful stuff in there which can just as well be applied to DIY shop machines.

My understanding was that for dust extraction/hazard control the other relevant piece of legislation is called ATEX (an EU diirective) which came into effect this summer and refers (in part) to the safe design of commercial/industrial dust extraction equipment to prevent secondary dust explosion in the workplace. Still trying to grips with that one as the HSE hasn't yet published guidelines... If there is something else I've missed, please tell me as "ignorance of the law is no defence"...

Scrit

 

[Midnight]

Mike - I agree that some form of extraction figure would be useful for the machines. Industrial machine manufacturers already supply this information - pity is that it is normally hopelessly inaccurate, which is why the DX companies tend to have their own tables for machines.

Glad to see you've looked at Bill Pentz's site, but there are lower cost alternatives than going to a 2000cfm unit or one of Bill's cyclones, such as fitting a better impeller (take a look at the Oneida Air site I quoted above to see what I mean) or welding vane extensions onto your existing impeller plate (I had a link for this, but I can't find it, if I do I'll post it). Part of the trick with the Oneida uprades is that they open out the baffle/inlet plate on the DX from 4in to 6in. Another thing to try is replacing the filter sock on your chip collector with a better-quality 2-micron (or less) bag from a reputable manufacturer. A good filter sock reduces the back pressure on the chip collector and the flow rate increases, providing that you've got large-enough pipework.

Scrit

Scrit
When I first came across the HSE guides about 18 months ago I musta missed the line saying that dust collection wasn't part of the PUWER codes. I stand corrected. Thanks. That said... I find it kinda ironic that they legislate against potentially dangerous machinery, yet leave dust collection as merely a recommended action. Red tape... go figure...

Reading Bill Pentz's site (I spent about a month there, 6 months ago) the one thing that leapt off the page was that unless you run a minimum duct size of 6", you're wasting your time trying to upgrade any other part of your DC; a 4" duct just can't flow enough air to let more powerfull motors, larger or better shaped blades make a difference. Sure, it'll work... for a time... but with it's reduced flow rate, blockages will start to build up, further restricting your flow rate.
Reading further, it became obvious that Bill's spent months going into this. I just don't have that kinda time available to do the same, which is why the best option for ME at least is simply to upgrade to a much more powerfull DC. There's no way I could install a properly plumbed in system in my tiny shop, machines are seldom set up in the same place twice. Instead, I simply wheel through the large shop vac when necessary and couple it directly to the machine requireing it.
Worst thing bothering me is that not even an upgraded DC is going to totally take care of my dust prob. I can't figure how to interface it to the single worst group of mess makers in my shop; most dangerous bunch too, my sanders. I can couple the smaller ones directly to the shop vac, power them through the vac's pto... but the larger sanders... sheesh... the 125mm RO uses one of them cartridge type collectors. Perfect if you can complete the job in less than 3 minutes. Next to useless of you're working anything bigger than a pencil box. Stopping to empty it every 3 mins is a royal pain in the proverbial... As for the belt sander.... I'm not gonna go there...
I'm toying with the idea of buying one of them ceiling mounted air filters. I'm trying to adapt my techniques to use hand planes and cabinet scrapers more than jointers and sanders, but there's no way I can totally escape creating dust.
Any thoughts...??

 

[Scrit]

Hi Mike

I seem to recall that there was a link from Bill's site to someone who had built a successful system based around 4in pipe, but that the guy had needed to do a full set of calculations to make it work.

In a previous shop I managed for a year or more with a deWalt single bag chip extractor on a trolley which was wheeled between machines as required. I think that unit came with a 5in hose as standard and was rated around 550cfm. It worked well enough (12in saw bench 10 x 7 P/T, disc/belt sander, small spindle moulder, router trable, etc) until I bought a 16in planer, and at that point its lack of suck became all too apparent. A plumbed-in system followbed shortly thereafter....

As I work at this for a living I find some of the legislation a bit of a pain at times, none more so than when an EU Directive (e.g. ATEX) appears and the decision is taken to reclassify wood dust as a "potentially explosive compound" - at which point everyone scuttles round trying to figure out which piece of legislation will, in effect, be retrospectively enacted against your business. Very frustrating!

As to portable machines, I've found the best approach is to build a downdraft table connected to the same DX unit you use on the rest of the machines. Beats the pants off trying to extract from the machine itself

Scrit

 

[Midnight]

As I work at this for a living I find some of the legislation a bit of a pain at times, none more so than when an EU Directive (e.g. ATEX) appears and the decision is taken to reclassify wood dust as a "potentially explosive compound" - at which point everyone scuttles round trying to figure out which piece of legislation will, in effect, be retrospectively enacted against your business. Very frustrating!

Reminds me of the LOLA mess I have to deal with at work.... sheesh...

As to portable machines, I've found the best approach is to build a downdraft table connected to the same DX unit you use on the rest of the machines. Beats the pants off trying to extract from the machine itself

Funny you should mention downdraft... that WAS going to be the next project... till SWMBO asked if I could handle a "quick job" for her....

Ahem.....

Got any links for doghouse plans...?? I need some new temporary accomidation.....
Scrit