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Debbie Battaglia
03-14-2007, 10:20 AM
I've been reading some posts on fine wood dust collection and the issue of which dust collector to buy. While I'm sure that everyone who responds is well-intentioned, we have to remember that not everyone is an expert. Just because someone says they bought a certain system and it works great doesn't mean the system is effective. In fact, my question is, who IS an expert?

If the most hazardous dust is invisible, how do we know what's escaping into the shop's air? From what I gather, there are a lot of places where things can go wrong, from inadequate collection at the tool site, to poor duct design or connections, to inadequate features in the DC itself, etc. I understand the vagaries of predicting exactly what health effects dust will have on a given person, but building a fault-proof DC system itself ought to be easy enough for engineers to figure out.

I've been leaning towards buying a Clear Vue cyclone, but dragging my feet somewhat because I'm afraid of investing it it, plus all the ducting, only to end up with a false sense of security that my shop environment is virtually free of fine dust. Probably more of us would be willing to sink money into a good system if we felt certain it would do what we want it to.

Is there a way to test the air once your system is in place (that isn't prohibitively expensive)?

Sorry about the rant! This is a very frustrating topic!

Debbie

Jim Becker
03-14-2007, 10:30 AM
IMHO, you need to put faith in your own comprehensive plan for dust collection and personal protection. A well-tuned collection system that gets as much material at the source is your first line of defense...and from there, you need to decide if and when you'll wear said personal protection. I doubt that there is any practical or cost effective way to scientifically test your shop environment, however.

Ted Miller
03-14-2007, 10:40 AM
Debbie, Welcome to the creek. Its not just DC but air purification you must worry about as well. You are 100% correct, and as I say "its the stuff you don't see that will kill you". IMO the chips and saw dust is not my concern, its the finest invisible of particles that are always on my mind. Venting your DC outside or keeping your shop open if you can with a constant flow or air out of the shop is the best way to go while operating machines...

Doug Arndt
03-14-2007, 11:40 AM
Debbie, here's a thread you should find interesting

http://www.sawmillcreek.org/showthread.php?t=44601

Jim Mackell
03-14-2007, 1:00 PM
Is there a way to test the air once your system is in place (that isn't prohibitively expensive)?

Debbie

Debbie, for me the final test was the way my lungs and sinuses reacted. Before dust collection I could work about an hour and then had to laydown to decongest. After dust collection I can work all day with no problems. Would not work with it any more than I would work without my safety glasses, it's that important to me.

There is no perfect one-size-fits-all system. What works for me may not help you at all. Good luck in making your decision.

Paul Johnstone
03-14-2007, 1:52 PM
I've been leaning towards buying a Clear Vue cyclone, but dragging my feet somewhat because I'm afraid of investing it it, plus all the ducting, only to end up with a false sense of security that my shop environment is virtually free of fine dust. Probably more of us would be willing to sink money into a good system if we felt certain it would do what we want it to.


Hi Debbie.

I had the same concerns as you. I am in the process of installing a ClearVue and the ductwork that goes with it. It's only going slow because I have such little spare time.

In my mind, the Clearvue had the Bill Pentz design, and that won me over.
I also am going to continue to run my air cleaner (JDS), open a window with a fan blowing out, and continue to wear my dust mask.

I have faith that Bill did all he could to make the system as safe to health as possible. Yet he even says on his own site (which I'm sure you've seen), that you should still have negative pressure (fan out the window, whatever) and wear a good dust mask.

In the end, that's all you can do. Buy the best system you can afford and take other precautions. Either that or give up the hobby.

I also plan on getting the a Festool random orbit sander and vac.. Yes, it's expensive, but my current ROS puts out a ton of dust when I use it. The festool demos I seen are very impressive. I think it's more effective than a downdraft table. Or I may get the Fein version.. not sure.

Steven Wilson
03-14-2007, 2:23 PM
If you're that concerned then get a chip collector (just a big, single stage, bag unit) and wear a full face respirator (full mask, powered air flow, HEPA filter) when you're in the shop. If you have skin reactions then add Tyvex coveralls to the respirator.

Debbie Battaglia
03-15-2007, 5:48 PM
I also plan on getting the a Festool random orbit sander and vac.. Yes, it's expensive, but my current ROS puts out a ton of dust when I use it. The festool demos I seen are very impressive. I think it's more effective than a downdraft table. Or I may get the Fein version.. not sure.

Paul,

I recently compared the stats and prices on the Fein turbo III vacuum and the Festool C22. My boss bought the Festool and paid, i think, $425, which included a HEPA filter. It has a static water lift of 90". I bought the Fein, because it has 99" and is a good deal quieter (58 db.) I've used the Festool with an orbital sander (not Festool brand tho) and it is kind of annoyingly loud (72 db) and leaves a film of dust on the wood. I called Festool about this and they told me the Festool sander has a central 6th hole that makes it collect dust better -- "there shouldn't be dust left behind" -- tho i'm skeptical about this. The Fein turbo III was about $360, brand new, on ebay, from a certified Fein dealer. The HEPA filter cost me $94 extra from the same dealer. I bought this one because of the greater suction and quieter operation, and the initial cost was good. However, i must say that, with my Rigid orbital sander, there's also a fine film of dust left behind. I probably could have been more concise with this, but i guess the bottom line is that they seem to work about the same (non-scientific conclusion), but the Fein is quieter.

Hope this helps with your decision.

Debbie

Jim O'Dell
03-16-2007, 10:11 AM
Debbie, I have the Clear Vue and I really like it. I don't have the overhead blade guard built yet for the TS, and haven't hooked up the portable tools to it, but when I'm cutting MDF, the room doesn't have the haze it used to have. Call or e-mail Ed at Clear Vue and ask him if there is anyone in your area that has one you could visit. He will be very accomodating. He has asked me if I would mind answering questons for someone before. I'm sure he would locate someone that could help you with your decision. Jim

Debbie Battaglia
03-16-2007, 5:33 PM
Jim,

Thanks for your feedback about the ClearVue. And I like your message about peace starting at home. Nice to see someone using the "P" word.

Debbie

Eric Wong
03-16-2007, 6:36 PM
I also have a ClearVue, just finished installing it. Love it! Its very powerful, and has very good separation efficiency (I think that's the right term...). Definitely check out Ed's website.

Ron Blaise
03-16-2007, 6:55 PM
Debbie:
If you want to test your air, you just have to observe your shop air in direct sunlight. I have a dust collector and an air purifier. the purifier will remove the little bitty bad stuff you don't normally see. The dust collector, no matter how good it is will put very fine dust in your shop atmosphere. When my purifier has been on for no more than 5 minutes, I see absolutely no fine particles in the sunlight. Works for me. Get one for your shop, your lungs will thank you. By the way, American Woodworker Magazine tested many purifiers and said the Delta unit was best dollar value and very effective, that's what I have.

John Gornall
03-16-2007, 10:17 PM
I'm telling this in all seriousness.

I have a friend that uses his nose to check his dust system and he has a serious commercial shop.

After a half day in his shop he blows his nose and if the tissue is clean all is well - if not he works through his dust system for problems. He's fussy about this. He also has his workers report any nose problems.

Jim O'Dell
03-16-2007, 10:26 PM
John, that requires me to try to make a joke. :eek:
How can you tell if a woodworker is happy? Check his kleenix at the end of the day! Jim.

John Young
03-16-2007, 11:17 PM
Means are available to the average woodworker to measure particulate matter in the air. I have used a few at work that are quite accurate that I can expand upon. One was a hand held real-time dust monitor that would output the concentration of dust in the air within the test chamber. You can walk around and map out dust concentrations by area. I rented it for a week and gained quantitative knowledge of areas and equipment to improve dust containment/collection in my plant. It was quite easy to use. Do a search for Casella or real time dust monitor.

A more traditional method for determining exposure to dust is to wear a collection/filtering device. You would wear it around the shop for a certain duration. You weigh a filter and then put it into the unit. The unit pumps air through a filter at approximately the human breathing rate. At the end of the duration, you take out the filter and weigh it or send it out to be weighed.

Bill Pentz
03-17-2007, 3:05 PM
How do we know our dust collectors are actually effective?

I've been reading some posts on fine wood dust collection and the issue of which dust collector to buy. While I'm sure that everyone who responds is well-intentioned, we have to remember that not everyone is an expert. Just because someone says they bought a certain system and it works great doesn't mean the system is effective. In fact, my question is, who IS an expert?

If the most hazardous dust is invisible, how do we know what's escaping into the shop's air? From what I gather, there are a lot of places where things can go wrong, from inadequate collection at the tool site, to poor duct design or connections, to inadequate features in the DC itself, etc. I understand the vagaries of predicting exactly what health effects dust will have on a given person, but building a fault-proof DC system itself ought to be easy enough for engineers to figure out.

I've been leaning towards buying a Clear Vue cyclone, but dragging my feet somewhat because I'm afraid of investing it it, plus all the ducting, only to end up with a false sense of security that my shop environment is virtually free of fine dust. Probably more of us would be willing to sink money into a good system if we felt certain it would do what we want it to.

Is there a way to test the air once your system is in place (that isn't prohibitively expensive)?

Sorry about the rant! This is a very frustrating topic!

Debbie

Debbie,

This is one of the tougher questions in woodworking and is far more frustrating to me than to most. There is tons of bad news on the dangers of fine wood dust and fine particle matter (do a Google search on “PM health risks (http://www.google.com/search?q=pm+health+risks&rls=com.microsoft:en-us&ie=UTF-8&oe=UTF-8&startIndex=&startPage=1)”). Essentially this news says that every dust exposure causes some measurable permanent damage and this damage accumulates over time based upon exposure. OSHA testing shows most small shops end up with two to five times the maximum airborne dust levels permitted in large commercial shops that receive regular air quality inspections. The medical research is clear that at these exposure levels most can go about 20 years before developing a serious health problem. If you are blessed with a really strong immune system you might go forty years. If you screw up and work the wrong woods without wearing a good respirator mask you could land in the hospital tomorrow.

I bought the top magazine rated cyclone system and vendor ducting only to immediately be frustrated because that system moved a fraction as much air as the smaller dust collector it replaced plus the cone, filter and ducting kept plugging. Then to add insult to injury I landed in the hospital a few months later and nearly died. I worked the more dangerous woods known to rapidly build up serious allergic reactions. Because my new cyclone filtered off most of the visible dust my clean looking shop left me with a false sense of security. OSHA medical air quality testing later showed my shop and home badly contaminated. Most of this dust was fugitive dust, meaning dust that previously escaped collection and went right through my too open filter. Airflow from my tools, dust collection system, air compressor, etc. kept launching that dust airborne again and again. The testing showed my home also contaminated so taking off my mask and going inside just continued my exposure.

I filled my time off work figuring out what went wrong and how to make repair because I did not want to either give up my tool collection or woodworking hobby. Although I started by trying to fix my cyclone and shared what I did on my Cyclone Modifications (http://billpentz.com/woodworking/cyclone/CycloneMods.cfm)pages that most vendors now copy, I was never able to get the separation level good enough to avoid quickly ruining filters. That is why I ended up coming up with my own more efficient cyclone and shared what I learned on my Cyclone and Dust Collection Research (http://billpentz.com/woodworking/cyclone/Index.cfm)web pages.

Last year I purchased a high end meter that gives both particle counts and milligrams of dust per cubic meter of air. I spent last quarter running all over California doing air quality testing on small wood shops and now have these meters moving between friends in different parts of the country. To my knowledge not one single shop has passed at the not so healthy OSHA air quality levels that had a 3 hp or smaller cyclone or 2 hp or smaller dust collector. Likewise, no matter how big the dust collector or cyclone not one shop passed that did not upgrade their tool hoods to block the dust laden airflows, control that dust and deliver it for collection. So far the only shop with a dust collector that passed the air quality tests had the dust collector located outside with no air returned into the shop. The only cyclones that have passed the OSHA and ACGIH standards had 5 hp cyclones with either fine filters or the air being blown directly outside. Nine of the shops I tested had 5 hp cyclones. Four failed outright due to poor hoods that let the dust escape before it could be collected, so just having a big cyclone is clearly not enough. At the current testing pace it is going to be at least another six months before I get back the test results from the others who are using my meters. When those results are in I will be co-authoring an article with a professor friend to be published by one of the ACGIH groups.

bill