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Grizzly G0440 2Hp Cyclone Dust Collector (2008)


G0440.jpg

    Likes:
  • Sucks like there's no tomorrow.  Pleny - and I mean plenty - of airflow to support my ~400 sq ft basement shop. 
  • Easilly supports 6" diameter main ducts.
  • Excellent fine dust seperation (very minimal dust makes it to the filter). 
  • The filter is rated for very small particle sizes - very little hazardous dust makes it back to the shop air.
  • Easy to clean the filter canister by pulling cables which in turn pulls a round brush through the innside of the filter stack.
  • The dust bin rolls around easily on low profile casters.
  • Excellent manual with clear instructions.  Grizzly has made great strides with the quality of their manuals in recent years.
  • Got it for a great price - before the 2009 price increase and with 20% MS Live Cashback thru eBay.
    Dislikes:
  • Noisy.  Much louder than my old Jet cannister DC.  The accessory muffler ($45 extra) does help reduce the noise level (details below) and is money well spent.  It's almost tolerable with the muffler, but I still plan to implement additional noise abatement treatments in the future.
  • Kinda large.  I did manage to squish it in a corner of my shop so that it fits in about the same space as my old Jet cannister DC, but that was a bit challenging (details below).
  • Emptying the drum isn't impossible, but it would be easier with some sort of bag.  I plan to make a home-brew bag holder sometime soon.
  • Not very easy to tell if the cust bin is full.  I'm concerned I'll overfill it someday, so I may look into some sort of bin level detector.

Noise Abatement:
Here is the first in a series of modifications intended to reduce the noise from my G0440.

I pay the mortgage as a noise and vibration engineer so I have easy access to a bunch of cool noise measurement equipment. For this test I instrumented my shop with 4 diffuse field microphones. The first was located in close proximity to the filter stack, the second was located in close proximity to the cyclone body (I named that one drum to mean the body of the cyclone an not the chip collection drum - bad nomenclature on my part), a third was placed 3' from the cyclone at ear level, and the fourth was placed 10' from the cyclone at ear level. The cyclone is mounted to a concrete wall in the corner of my 20'x20' basement shop (see pic earlier in this thread).

The data below is intended to quantify the effects of installing the Grizzly muffler (which is just a simple "glass pack" type muffler stuffed with acoustic absorptive foam) on the outlet of the cyclone immediately before the filter stack. Pain in the patootie to install by the way. The green bars in the background show the noise levels at each of the 4 mics before installing the muffler, and the blue bars in the foreground show the noise levels after installing the muffler - both as a function of frequency as shown on the x-axis. The #'s in the legends and on the big bars to the right of each plot are the overall levels for these tests which is what you often hear folks reference with handheld noise meters like you can buy at Radio Shack. Each of the 4 plots is data from an individual mic as labeled in the title legend. I hope all that makes a modicum of sense.....

G0440MufflerEffects.JPG

Conclusions:
* The Griz muffler is effective. It reduces the 3' and 10' mic overall levels by 5 to 6 dB(A) which is quite respectable for a simple glass pack muffler.
* Most of the noise appears to come from the filter stack (although I didn't do a thorough source mapping)
* After I came upstairs my wife asked me what I did to quiet that ^&%$ dust collector. Unprompted by me. That right there was worth the money and time to install the filter - she noticed a clear difference. She still said it was far from quiet, but it was much better.
* I noticed a significant improvement in the shop as well. I'll still need to do more to quiet it down, and I'll still need to wear hearing protection till that happens, but it is definitely better. Not a panacea, but an improvement for sure.
* Note that my shop is quite reverberant, so these #'s may be a bit higher than you'd measure in other shops.

The next few things I try may not happen for a little while do to an upcoming busy work period.  I'll be trying absorption around the filter stack, absorption on the walls, and possibly an acoustic enclosure around the whole thing if needed.

Copyright 2009 Chris Billman