Wood Magazine to Test Whole Shop Cyclones

[Ole Anderson]

Quick question for the DC purists here: Given that fine dust is considered a significant long term health risk, do any of you use the 'air cleaners' like the Jet - that recirculates air and filters dust.

How does the efficiency of this compare to a DC system?

Im curious because it certainly stirs things up - wondered if this was a good thing or a bad thing.....

I use both a DC and an ambient air filter because I believe they complement each other. Not every shop operation lends itself to good collection of the dust at its source: hand sanding, freehand routing, and sheet goods breakdown with a traditional circ saw to name a few. For a more definitive answer as to whether they are a "dust blower' or if they contribute to the cleanliness of your shop air, I defer to those with a Dylos particle counter. There have been a number of posts in that regard and my interpretation of those is that the ambient air cleaner serves its purpose.

[ian maybury]

I guess the difficulty Chris is that the answers to dust collection questions can easily be expressed in a few words IF that is everybody that is party to the discussion shares the same basic assumptions and vocabulary. Which is probably why we seem to be reasonably well agreed that a dust collection manual for small shop woodworking would be so useful.

I have to agree too (with those like Michael) that this stuff can be expressed pretty simply. It isn't rocket science, it was mostly worked out years ago, and at our level there's no significant disagreement i believe on either requirements (the 1 - 5mg/M3 TLV air quality standard is pretty much standard now across the western world in industry), and on the technical options by which it may be delivered.

The confusion is peculiar to the DIY and hobby dust collection field where the relative weakness of the individual buyer (in terms of their power as a customer) and the readiness of some of the industry to exploit the absence of regulation has created a free for all of competing and (especially versus the aforementioned good industrial practice) conflicting claims. Put simply - when push comes to shove there would be much less debate and little confusion if the agenda was limited to genuine issues.

As another that tries to respond to questions posted here it's worth again repeating some of difficulties that often arise. (a) Many are not aware of and are not disposed to accepting the health risk of fine dust, (b) they are exposed to all sorts of competing views regarding risks and solutions, (c) many already have their minds largely made up on a purchase when they post - with the result that you end up trying to roll back the thought process - or at least to maximise performance within already decided constraints, (d) most are not up to speed on even the basic technicalities, so it's necessary to keep on restating stuff to create context before answering questions, (e) the information posted with questions is rarely complete, (f) the sources of public information that people can be steered towards are limited, incomplete, use differing formats and terminologies, and in locations all over the place, (g) there's inevitably gaps in the information that we can draw on anyway - time and again it's possible to progress a discussion so far, but not possible to be definitive in the advice given because the information is not published by the makers and (h) information that conflicts with the message that some want to hear can draw flak.

Bill P as you say has proven to have been very much on the ball when he more or less standardised (in as much as this is possible) on 6in ducting, close to HEPA standard filtration and a 15 or 16in impeller for one machine at a time for small shop dust systems of up to a specified maximum duct run distance and the sort of machines we tend to use. The simple answer to every question that comes up is to very firmly say 'go fit one' if you want to be safe. Inevitably though we end up with lots seeking to use lesser specification kit, and others arguing in favour of it.

Much like Alan i for this reason too have mostly pulled back from answering questions except those about solutions pitched at the Bill P level. On the basis that (a) i don't have direct experience of much of the equipment mentioned, (b) i don't want to seem to advise that low HP/small impeller systems are appropriate when often it's very clear that they will be highly marginal if used in the proposed manner, and (c ) pushing the point that a well specified system is essential is likely to lead to conflict which would result in the message that higher spec systems are advisable being lost in the resulting argument. (not to mention that it'd be great if ways can be found to do the business with lower cost solutions, or even that there aren't free flowing short run/hose scenarios with carefully designed tight hoods where less airflow can do a decent job)

+1 that a good ambient filter is a useful bit of kit Carl - provided that is they are seen as an extra/add on that adds value in situations where it's impossible to capture all of the dust at the point of work, and not as a justification for reducing the spec of a 'point of work' dust collection system. It's worth saying though that a Pentz style dust system with good quality filtration does most of the job that an ambient filter does anyway - that's one of the reasons the CFM is set so high..

ian

[Chris Parks]

Chris, I'm assuming you were referring to my post.

Mike, no I did not mean to be specific about posts in this thread, it was meant as a general observation and one which I have made before. Your offer to put up a glossary of terms will be much appreciated but on thinking about it unless it is a sticky of some sort will be buried within a few days. Good collection at the machines means the least amount of fine dust is lost to the atmosphere during cutting or machining operations. I guess the standard is dust released to the atmosphere, if it exceeds a legislated standard then improvements are needed.

I notice I did not get a reaction on linking from this forum to other places that might have useful information or insights on this topic and that might keep members of this forum healthier or give them more ideas on dust extraction. As I said this is people's health we are talking about and not a popularity contest judging what forum might be best.

[Michael W. Clark]

Chris, I would be interested in reading other information. Feel free to PM me with the link.

How do you make it a sticky? I ll post it in a new thread for review & comment. Give me a few days.

Maybe the sticky is an avenue for an intro and basic info on airflow and DC?

[Chris Parks]

Mike, it is up to the mods to make a sticky thread. I wil send you a link to another forum with a DE subforum.

[Jim Neeley]

I wonder if Chris Schwarz / Lost Art Press would be up for publishing such a book if it were developed by competent writers, like some here? While he's primarily hand tool oriented, he's also a big one for providing the straight poop and since he has control of the publishing company.... Hmmm???

[Phil Thien]

The biggest problem I see in writing any book is a lack of underlying agreement over how much DC is actually necessary.

I know a few years ago some started making the connection between wood dust being a carcinogen and/or allergenic, and the need to capture all fine dust.

Wood dust is a carcinogen, BUT, we're exposed to all sorts of carcinogens. The question really boils down to, are hobbyist woodworkers likely to develop disease as a result of their level of exposure?

Taken union carpenters, for example. These guys are exposed to far more wood dust than any hobbyist. And they rarely use DC besides maybe a bag on their tool (and I'm being generous there, they mostly toss those). And I've personally watched as they've ripped three sheets of plywood in one shot, creating an undeniable wood dust mushroom cloud.

If moderate exposure to wood dust was a problem, then those guys should be dropping like flies.

I'm not saying there is no hazard to wood dust. And some carpenters do develop occupational asthma (although I think a lot of it is due to specific products they're dealing with).

And I'm not saying measures should not be taken.

My point is, there needs to be some scientific evidence showing that: (1) A 3-HP cyclone with fine filters works some percentage better than a single-stage unit with 1-micron bags in actual real-world conditions. And (2) The difference in performance between those two is warranted even for part-time hobbyist woodworkers.

And does a cyclone outperform or underperform a single stage when the single stage is used in combination with an ambient air cleaner? And if you use an ambient air cleaner in combination with both, what kind of real-world differences are there.

So I think any book should start the discussion with "conclusions we can draw from occupational asthma cases" and move on from there.

[Chris Parks]

Phil, I have seen you follow this line before. My comeback to that is everyone takes choices when it comes to wood dust and we have to live with them but they should be informed choices, well as informed as they can be at this stage of DE development. You take the choice that some fine dust is not a problem, that's fine with me but I take the opposite view and always have even before I became commercially involved. At what level is too much or little? The background pollution will vary with the locale so we do we measure it against that? As I said your choice and my choice and I prefer to minimise it. Just because someone jumps off a cliff (your union woodworkers) does everyone jump with them or even use them as a yardstick in the amount of dust it is ok to breathe? I have had numerous people come to me with stories that involve health issues due to dust ingestion and some have had to give up woodworking because of it, now tell them it is ok to breath wood dust.

[Alan Schaffter]

The biggest problem I see in writing any book is a lack of underlying agreement over how much DC is actually necessary.

I know a few years ago some started making the connection between wood dust being a carcinogen and/or allergenic, and the need to capture all fine dust.

Wood dust is a carcinogen, BUT, we're exposed to all sorts of carcinogens. The question really boils down to, are hobbyist woodworkers likely to develop disease as a result of their level of exposure?

Taken union carpenters, for example. These guys are exposed to far more wood dust than any hobbyist. And they rarely use DC besides maybe a bag on their tool (and I'm being generous there, they mostly toss those). And I've personally watched as they've ripped three sheets of plywood in one shot, creating an undeniable wood dust mushroom cloud.

If moderate exposure to wood dust was a problem, then those guys should be dropping like flies.

Phil, your point is a good one, but it may be that not enough historical health data has been collected on these workers. There are better examples too, since it wasn't all that long ago that carpenters used handsaws. Now, while they may use circular saws which often generate more large dust particles than fine ones, they often use them outside where the dust quickly blows away and the concentration reduced. I would like to see numbers on wood floor finishers. Most of the big floor sanders I've seen and used generate tons of dust and the supplied collection bags look like a 25 micron dust pump supplied with early DC's.

One point often overlooked, too, when making comparisons especially between industry and home shops- in the early days and well into the industrial revolution, there were few power tools and no belt/drum sanding machines. In fact, much of the heavy producers of fine dust haven't been around for too long. Industry, unlike most home shops, typically has better dust collection in a space with an interior volume many times that of home shops. Many heavy dust producers haven't been in home shops until recent years either- most weren't invented or were unaffordable when my dad had a home shop, especially sanders- ROS, disk, belt, drum, and wide-belt sanders. Now, machines like drum and wide belt sanders which were limited to commercial shops, can be found in many home shops and may therefore generate more dust than their commercial relatives which are usually connected to monster DC systems, all in a much more confined space that can result in much higher concentrations of dust. Bottom line, I would be more concerned about the health of woodworkers in today's well-equipped home shop than those working in industrial environments.

[Chris Parks]

Alan, spot on.

[Phil Thien]

Phil, I have seen you follow this line before. My comeback to that is everyone takes choices when it comes to wood dust and we have to live with them but they should be informed choices, well as informed as they can be at this stage of DE development.

Not sure what you mean by following a line. If I hadn't found and organized the first group buy of Dylos particle counters (which ultimately led to I think at least two to three other group buys), most everyone would still believe that our shops are full of toxic dust that never settles. I'm the one that has been INSISTENT on data. I have been INSISTENT on informed choices.

You take the choice that some fine dust is not a problem, that's fine with me but I take the opposite view and always have even before I became commercially involved. At what level is too much or little? The background pollution will vary with the locale so we do we measure it against that? As I said your choice and my choice and I prefer to minimise it. Just because someone jumps off a cliff (your union woodworkers) does everyone jump with them or even use them as a yardstick in the amount of dust it is ok to breathe? I have had numerous people come to me with stories that involve health issues due to dust ingestion and some have had to give up woodworking because of it, now tell them it is ok to breath wood dust.

Wow, all I can say is that your post is long on subjective data, and short on objective data.

My point isn't that some fine dust is okay. My point is, nobody has proven it isn't.

My point is, outstanding results (equal to any cyclone) can and have been achieved with a single-stage DC, 1-micron bags, 4" ducting, and an ambient air cleaner. The results are outstanding in an objective way: The air has been measured.

My point is that we need to be objective.

Scare tactics and extremism are the wrong approach, IMHO.

[Phil Thien]

Phil, your point is a good one, but it may be that not enough historical health data has been collected on these workers. There are better examples too, since it wasn't all that long ago that carpenters used handsaws. Now, while they may use circular saws which often generate more large dust particles than fine ones, they often use them outside where the dust quickly blows away and the concentration reduced. I would like to see numbers on wood floor finishers. Most of the big floor sanders I've seen and used generate tons of dust and the supplied collection bags look like a 25 micron dust pump supplied with early DC's.

One point often overlooked, too, when making comparisons especially between industry and home shops- in the early days and well into the industrial revolution, there were few power tools and no belt/drum sanding machines. In fact, much of the heavy producers of fine dust haven't been around for too long. Industry, unlike most home shops, typically has better dust collection in a space with an interior volume many times that of home shops. Many heavy dust producers haven't been in home shops until recent years either- most weren't invented or were unaffordable when my dad had a home shop, especially sanders- ROS, disk, belt, drum, and wide-belt sanders. Now, machines like drum and wide belt sanders which were limited to commercial shops, can be found in many home shops and may therefore generate more dust than their commercial relatives which are usually connected to monster DC systems, all in a much more confined space that can result in much higher concentrations of dust. Bottom line, I would be more concerned about the health of woodworkers in today's well-equipped home shop than those working in industrial environments.

A lack of data is only a lack of data. We can be cautious, but we cannot assume based on intuition that home wood shops are less safe than industrial environments.

The problem with many of these arguments is that nobody in medicine/academia has done the research to correlate moderate and occasional exposure to wood dust to any sort of disease.

The reason is probably that nobody in medicine/academia suspects moderate and occasional exposure to wood dust to be the cause of any sort of disease.

The reason is probably that nobody in medicine/academia has been confronted with any reason to suspect moderate and occasional exposure to wood dust is the cause of any sort of disease.

Furthermore, a simple single-stage DC with 1-micron bags and 4" ductwork, in combination with an ambient air cleaner, is pretty hard to beat. Nobody with that combination that purchased a particle counter was alarmed to find that is wasn't effective. On the contrary, they seem to be breathing air substantially cleaner than any jobsite carpenter.

Again, if the guy working in his home shop a few hours here and there (with the above reasonable dust collection efforts) is working unsafely, then a jobsite carpenter is absolutely doomed.

[David Kumm]

I think there is truth to all sides here. The absolute worst collection systems I've seen are in small commercial shops and the guys I've talked to don't seem as concerned as many of us hobby guys are. I've seen 43" widebelts with a 2 hp single bagger and dust everywhere. My interest in collection started with my wife complaining about dust in the house coming from the shop and then watching my Dad cope with oxygen. I don't know how important any of this is but if I'm going to put forth the effort to capture dust and chips I want to be fairly complete about it. In the past few years hobby machines have gotten larger, 20 and 24" planers, big saws, and edge, drum and widebelt sanders are now common. Dust collection is just starting to catch up. Phil might be correct in that the dangers are overstated but I don't think a small bagger will handle all the machines used anymore with any degree of safety. Lunchbox planers and small jointers probably but it is difficult to make any broad statements about what will work. Even a 5 hp 6" main didn't come close to handling my older machines. It took several upgrades to find the combination that would handle my stuff and while it may be larger than average there are lots of big old machines out there and lots of sanders in home shops. I believe the discussion is valid but I respect both views. Dave

[Phil Thien]

My interest in collection started with my wife complaining about dust in the house coming from the shop and then watching my Dad cope with oxygen.

My shop is in my basement, and all my DC is via a shop-vac powered separator of my design. All the piping is 2.5" clear plastic stuff.

Tools I've used included a 16/32 sander, and I used (abused) that thing a lot. I also use my table saw, router table, two bandsaws, oscillating drum sander, Inca 8-5/8" jointer/planer, and now a Dewalt planer.

And my wife has never found any woodshop dust in the rest of the house, except maybe on the first 1-2 steps going upstairs from the basement. And I could eliminate that if I'd put a mat on the floor in front of the steps (which I won't do for safety reasons).

And I do a lot of projects/generate a lot of debris. In the last nine months, I've emptied a 30-gallon drum about six times (I only fill it to about 25-gallons because of the baffle).

And my particle counters are telling me my shop air is cleaner than outside, provided I'm running one of my experimental air cleaners.

LOL, what were you doing in your shop that was so darn messy?

[David Kumm]

Phil, my old 3 hp system couldn't handle my 25x2 double drum and later the 37x2. The Oliver 399 had straight blades and the strings were so long they plugged the 6" hood. The 24" Oliver had an ITCH head so had smaller chips but the hood design wasn't great. It really need something higher than 1400 cfm to keep stuff from going into the air and now I run about 1800 into it. The 16" jointer needs about 1400. The Oakley edge sander had no great way to deal with dust so I made a hood but it still needs about 2000 cfm to pull the dust over it's four foot length. My garage is about 2000 sq ft and it takes a lot to deal with the mess I am capable of. Dave