Houston - We have Suckage !!

[Doug Shepard]

Well it's been a long road, but I finally got the first machine hookup done this morning and powered up the DC to see how things work. So far, I'm a happy camper.

In a very ironic twist, it's been exactly a year since I started a thread with my ClearView DC installation saga and about a week after that when I got the unit powered up enough to run the brief shoebox test.
http://www.sawmillcreek.org/showthread.php?t=41911

The remainder of the fall months last year were spent building an insulated closet around the unit, putting vent and filters in the closet wall, getting filters and cleanout installed, bin sensor and alarm light wiring connected, and other odds and ends. Stopped working on the whole affair on Christmas day and didn't return to it until Mid April due to brutally cold temps here this winter. It was just way too cold to do any work in the unheated GaShop, even with the propane space heater running.

Been working on the ducting since April with quite a few detours along the way:
- Experiments with bending PVC with a heat blanket and wiring up the controller for the blanket. Didn't pan out as planned for bending the ducting, but it did get put to use flattening PVC for cutting into flanges around duct ends.
- Lots of experimenting to modify the LV blastgates in the rafters for spring loading so I can work them from below
http://www.sawmillcreek.org/showthread.php?t=58586
- Lots of experimenting to come up with the Rube Goldberg quick connects
http://www.sawmillcreek.org/showthread.php?t=62995

At this point the machine I'm using the most is the 12" disc/6x48" sander. I'm using the disc to square up the ends of PVC after cutting with the jigsaw. I was getting tired of spewing fine white dust around and will need to keep using it as I get more machines hooked up, so that's the one I started with. There's a couple of minor hose/fitting changes I want to go back and do, but right now it's functional. I'll get pics later of that.

One item I was extremely pleased with was the big decrease in noise since measuring it back around the time of the shoe-box test.
For comparison I'll put the original posted measurements in red. The new measurements now are with the surrounding closet, filters, ducts, chip bin, and machine hookup installed. FYI - a 3dB decrease is percieved by the human ear as 1/2 as loud.
6 ft from the DC - no filters, ducts, collection bin yet installed.
101 dB - C weighting
97 dB - A weighting
Same location
86 dB - C weighting
80 dB - A weighting
96 dB - C weighting with closet door open
90 dB - A weighting with closet door open

6 ft from the DC through a 8" concrete block wall with 1.5" styro insulation, drywall, and paneling.
71 dB - C weighting
57 dB - A weighting
Hopefully 2" styro on the DC side of that concrete block will get these last numbers down significantly.
Same location
66 dB - C weighting
50 dB - A weighting
The C weighting is checking 32-10000 Hz and the A weighting 500-10000 Hz.

The 2nd location was of particular concern as it's a living room area that's used mostly just during warmer weather (prime woodworking season for me). It's hardly even noticeable now.

Now just need to get some more machines hooked up.

[Jim O'Dell]

CONGRATS, Doug!! It gets easier from here. Jim.

[Russ Massery]

Oh Yeah! Another Clearvue Suckscess :D story. Congrats!

[Andy Calenzo]

Mr. Shepard,

This is Andy Calenzo and I am an engineer here at Oneida Air Systems. Thank you for your excellent post as the sound measurements you provided are very informative. We set up a Clearvue cyclone here and when we measured the sound level in our shop, we obtained similar results to yours. The key with a good dust collection system is to keep hazardous wood particles out of your lungs without paying a price of experiencing hearing loss. Your outdoor mounting of the dust collector is a great way to reduce sound. Unfortunately, in climates where the outdoor ambient air temperatures can become extreme (North in the winter and South in the summer), you should bring the air back into your shop so you don't freeze or cook. When you do this, you are bringing some of the sound back inside.
Our Gorilla systems come equipped with a factory supplied muffler that drops inside the filter cartridge. This allows you to hang the filter back in the shop and not pay the stiff price associated with a significant increase in noise. We also designed the impeller on the Gorilla to be as efficient as possible because this minimizes the amount of sound our dust collectors generate (many of our customers run their Gorillas inside their shop because with the factory supplied silencer, the sound pressure level as measured on the 'A' scale is in the low 80's). I would like to clarify one statement that you made: "a 3dB decrease is percieved by the human ear as 1/2 as loud". This is actually not true. Because the response of the human ear to sound is non-linear, it takes a 10 decibel increase in sound pressure for you to perceive it as being twice as loud (please see www.quietsolution.com (http://www.quietsolution.com) to obtain an excellent FREE reference on sound entitled 'Sound & Noise' - this document is available under their link 'White Papers').
To give you an idea of how significant impeller design can be, we ran the Clearvue at 9.7" of fan static without the filter and measured 90 dBA at a distance of 10'. We then ran the 3 horsepower Gorilla without a filter at the same fan static and measured 82.5 dBA at a distance of 10' - 7.5 dBA quieter. As you noted in your post, the fact that 3 dBA represents a doubling of measured sound pressure, a 7.5 dBA difference is VERY significant. Let me know if you have any questions about any of this and thanks again for your excellent post.

[Ed Morgano]

Mr. Shepard,

This is Andy Calenzo and I am an engineer here at Oneida Air Systems. Thank you for your excellent post as the sound measurements you provided are very informative. We set up a Clearvue cyclone here and when we measured the sound level in our shop, we obtained similar results to yours. The key with a good dust collection system is to keep hazardous wood particles out of your lungs without paying a price of experiencing hearing loss. Your outdoor mounting of the dust collector is a great way to reduce sound. Unfortunately, in climates where the outdoor ambient air temperatures can become extreme (North in the winter and South in the summer), you should bring the air back into your shop so you don't freeze or cook. When you do this, you are bringing some of the sound back inside.
Our Gorilla systems come equipped with a factory supplied muffler that drops inside the filter cartridge. This allows you to hang the filter back in the shop and not pay the stiff price associated with a significant increase in noise. We also designed the impeller on the Gorilla to be as efficient as possible because this minimizes the amount of sound our dust collectors generate (many of our customers run their Gorillas inside their shop because with the factory supplied silencer, the sound pressure level as measured on the 'A' scale is in the low 80's). I would like to clarify one statement that you made: "a 3dB decrease is percieved by the human ear as 1/2 as loud". This is actually not true. Because the response of the human ear to sound is non-linear, it takes a 10 decibel increase in sound pressure for you to perceive it as being twice as loud (please see www.quietsolution.com (http://www.quietsolution.com) to obtain an excellent FREE reference on sound entitled 'Sound & Noise' - this document is available under their link 'White Papers').
To give you an idea of how significant impeller design can be, we ran the Clearvue at 9.7" of fan static without the filter and measured 90 dBA at a distance of 10'. We then ran the 3 horsepower Gorilla without a filter at the same fan static and measured 82.5 dBA at a distance of 10' - 7.5 dBA quieter. As you noted in your post, the fact that 3 dBA represents a doubling of measured sound pressure, a 7.5 dBA difference is VERY significant. Let me know if you have any questions about any of this and thanks again for your excellent post.

Andy,
This is Ed Morgano. I'm president of Clear Vue Cyclones, Inc. Since Oneida-Air refused to sell us one of their units, you have me at a slight disadvantage because we haven't been able to do similar tests here at Clear Vue. I'm not disputing your numbers, just would like the opportunity to verify them for myself.
To clarify a couple of points: First, Doug has his cyclone mounted inside, not outside so his measurements include bringing the air back into his shop. Second, in our testing we have found that the more air you move, the louder it gets. Example: We measured the sound level of air moving through a 4" port at 82 db (A scale)....with the CV1800 hooked up to it. We have just completed a move into our new shop and installed our new "Max" system inside a sound insulated closet with the air returning back into the shop. Sound level right outside our closet measured a very comfortable 65 db. We always recommend putting dust collection (no matter who's it is) in a separate room, an enclosure inside or outside for noise reduction. Since a dust collection system runs more than any other machine in the shop, it's significant to make it as quiet as possible and for my money, 78 - 85 db is not a comfortable noise level unless you are wearing hearing protection.

Ed

[Doug Shepard]

Andy
Looks like I was remembering the actual reduction and not the percieved reduction. College Physics of Acoustics class was a long time ago.
Pulled this out of the white paper on their site.
Simply put, 3dB is not 1/3rd of 9dB, because the scale is not linear. In fact, noise is cut in half for every 3dB reduction, as measured by actual sound pressure, however our own perceived change in volume is about half as loud for every 10dB reduction. Said another way, each increase of 10 dB represents a 10 times increase in the power in the sound wave, but only a 2 times increase in the perceived volume by the human ear.


Just to put the numbers into perspective though. Standing at the belt/disc combo while it's running (with nothing against the disc or belt) I cant hear the DC which is about 15-18 ft away until I shut off the sander. In the family room adjacent to the shop and separated by inches from the cyclone (the 2nd set of dB numbers) it sounds for all the world like the blower on the house A/C unit kicked on. It might mean you'd reach for the remote and increase the sound on the TV by a bar (maybe 2 for quiet volume shows), but it's not the concern I thought it might be.

[Jim Dunn]

Doug congrats on your "suckcess" :)

I have to wonder though if the two competing company representatives wouldn't be better off to congratulate you and e-mail each other? Just wondering.

[Doug Shepard]

...
I have to wonder though if the two competing company representatives wouldn't be better off to congratulate you and e-mail each other? Just wondering.

Oh I dont mind. Makes me feel kind of like the new freshman co-ed with the 2 BMOC fighting over lil ole me. Guess I better get my hair done for the big weekend frat party.:D

[Mike Heidrick]

Ed,Andy,

What type of meters are you using to do your measurements with and what types of mics. How often are you calibrating those mics? There can be SIGNIFICANT differences in the results of sound measurement based on different dB meters.