Dust Collection Measurement

[Bill Pentz]

With a lot of help from friends and starting with work done a few years back by Jim Halbert that he gave me permission to use, I've finally got a draft of a new web page for measuring and testing dust collectors, cyclones, and ducting. Since this is still a draft, feedback would be most appreciated:

Cyclone and Dust Collection Research - Airflow Measurement (http://cnets.net/~eclectic/woodworking/cyclone/measurement.html)

bill

[Mike Mastin]

Bill,

I for one want to thank you for your work on this subject. There is so little valid information available from independent sources.

Jim Halbert and your research have educated and wiped away a great deal of the falsehoods that once was rampant with reagrds to dust collection.

I am very grateful and thankful.

[Paul Kunkel]

Probably THE most comprehensive article on dustcollecting ever!:) If you're talking with Jim-say "Hi" for me please. Thanks!

[Jim Becker]

I built Jim's measuring device about three years ago and it worked as advertised. In fact, I don't even know where it is at this point...several other local woodworkers have "borrowed" it along the way! Highly recommended and the "price is right".

[Rusty Hughes, Indy]

Wow, that's a name I haven't heard in awhile. I was always impressed with testing procedures and data.

Was Jim responsible for the story about Fluffy, the cat, and the dust collector? I only remember bits and pieces but I don't remember where it came from or if it was even true. If someone remembers Fluffy please retell it here. All I remember is that it was very funny and I was laughing for a long time.

Thanks
Rusty

[Mike Mastin]

I still recall the first time I read Jim refer to the "cat snatching power" of his dust collection system :-) Fluffy would clean the main trunk line as she was sucked into his cyclone (jokingly of course).

I have not seen any posts from Jim in any forums for a long while. By his own admission, he was confrontational with the dust collection manufacturers. Maybe they put a cease and desist order on Jim somehow.......

[Jack Diemer]

Rumor has it, he joined the secret service , and now monitors the woodworking forums as part of the President's home land security act.

[Bill Pentz]

Thanks for the support!

Jim is off on vacation now enjoying flying his model airplanes.., or maybe I should make up a story about the SPCA made him take a couple of spins in a large cyclone after what was rumored to have happened to his cat... but I don't think so.

*smile*

bill

[John Schreiber]

Bill,

Thanks for doing what you're doing. Dust collection is not the most exciting part of wood working and measuring dust collection is not the most exiting part of that.

Meaningful measurement is the difference between opinion and knowledge. A single measurement has more meaning than a thousand opinions.

We can hope that what you are doing will lead to more honest advertising and better products for all wood workers, but I'm not that optimistic about the marketplace. It will certianly result in better decisions making for those of us who pay attention and I personally thank you for that.

[David Rose]

influence to move our industry in a better direction. So much marketing today is just hype. People use to realize that "truth in advertising" (remember that term?) paid off. Maybe we will again one day. Until then, I am greatful for folks like you.

I think I understood you to say that a company will be opening in the future to offer a complete DC with "modern" technology. Is there any word on that yet? Do you think they will start with equipment that is tough for the starting woodworker to justify price wise?

David, whose health says he needs to quit investing in toys until safety issues are addressed..

[Bill Pentz]

John,

Thanks.. I agree. It's time for real facts and figures that vendors can back with real performance.

David,

I'm a little at a loss as to what you were referring to in terms of my saying a real firm would be stepping forward with better products. I know WoodSucker, Oneida-Air, and Dust Eliminator all offer very good cyclone products and advice today. Wynn Environmental is already helping hobbyists with very good prices and support on fine cartridge filters for cyclones and a custom design that folks can convert over some of the dust collectors to cartridges as well. American Fabric Filter has long put out top quality bags for a good price. TheGoodMember on eBay has helped at least seventy five people with good 2 hp motors that they have combined with the special airfoil impeller that Sheldon's Engineering went way out on a limb to custom design based on my statement of what hobbyist needed. Many more have purchased his motor and added 12" impellers to make their own dust collector blowers. Sheldon's also came through again with a less expensive and better quality material movement impeller that goes with the the Leeson motor I recommend and Electric Motor Warehouse sets up that motor all ready to go for my budget blower. Cincinnati Fan came through with a huge discount on one of their best quality impellers to help folks out that Terry Hatfield makes available along with his Dust Elminator kit version of my cyclone and budget blower designs.

I know at least five major hobbyist tool vendors have made significant changes to their products in part based on my reviews, suggestions and in two cases direct help. At least one other is using my web pages to overhaul their product line without so much as a thank you, but I admit being a little harsh to them in the past. I also think that my less than nice treatment of the nonsense claims on filtering is helping a little, but not nearly as much or as quickly I would like. Of course I'm getting old and cantankerous, so will not be happy until each comes up with an ASHRAE approved lab that gives me a certified filtering level at full airflow. Even with that I'm not going to be a really happy camper until I see a major vendor come out with a 6" port on one of their larger tools. That would say suddenly that fine dust collection is important and they realize it is not going to be picked up without moving that 800 CFM at larger tools which with our sized blowers needs a 6" duct. That will make my day!

There is no question at all that with the greatly increased CFM needed to collect the fine, most unhealthy dust that we needed better personal system testing as well. That's why I talked Jim Halbert into digging out his old articles on testing then spent much of my last two months updating that information.

*smile*

bill

[David Rose]

It sounds like I did.

<I'm a little at a loss as to what you were referring to in terms of my saying a real firm would be stepping forward with better products>

A month or two ago, when someone asked about an assembled DC using your/Terry's cyclone, I thought I understood that someone local (our area) was going to build something turn key in the near future. Something was said like "details could not be released yet". I am probably totally out of context. Sorry.

Anyway, I among many, appreciate your work, Bill, Jim and Terry.

David

[Michael Lutz]

I glanced through the webpage. For the last six years, I have tested airflows for a living, and I have to disagree about your comment of the Dwyer digital manometer being accurate. From my experience the 3 decimal place accuracy is a falacy. They also tend to bounce too much to get an accurate measurement. An incline manometer is much more accurate and repeatable when measuring velocity pressures. A slack tube will be close to as accurate as the digital manometer for the static pressure. Magnehelics are fragile and sometimes come directly from the supplier reading incorrectly. They should also be checked against and incline or slack tube depending on what you want to pressures you want to measure.

In my experience, it is difficult to accurately measure the velocity pressure in ducts less than 12" due to the wall effects. How repeatable are you measurements?

Mike

[Bill Pentz]

Michael,

So what constructive changes do you recommend?

bill