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Why didn't I ever think of this before?

My son was helping out in my shop during the holidays. I have a nice fuzzy yarn brush with a handle to brush off router table, jointer, and other surfaces that get covered with debri.

He got a bit too close as he was running the four inch dust collection hose and sucked that thing into my two horsepower collection system. A week later, I find it's stuck near the impeller and making a little noise.

After removal of the outer three tube connector, I reach in and pull the brush out of the blower housing. Okay, I said all that to say I was crouched down beside the collection system when it exhaled after the motor was shut off. Guess what? A major expulsion of dust came back through the unit and went all over. It just made me realize it does that each time it is powered up and shuts off.

It may be one reason our shops are dustier than we want them to be. These things exhale each time we shut them off, so maybe it would be good to have a four inch outlet to the outside to open and shut all others when shutting down? I believe I'll test this theory a bit but for sure it belched a great cloud out of the machine with the hose disconnected.

Mabe a check valve of some sort would be a good idea.

Al

My thought was an exhaust port to open out a window upon shutdown, of course that means all other ports would have to be shut in the shop.

Hey ...Why not just forget the bag, and port the whole exhaust out a window .. your neighbours will love you for it (uhhh, what dust ???)

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Tony, I've considered that, but I have to pay for the heat and cool man.....



I think I've come up with the answer. I'm considering porting in a small regular vacuum cleaner into the system. When I flip off the 9 foot tall collector, I flip on the small vac with bag for one minute, until the large bag is completely deflated. That way at least a little air flow is still created at an open shop port say in my General Drum sander which is connected most all the time. ?

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http://www.dickeyguitars.com

DO you have a separator in front of the collector ??? I have a large collector as well, and never notice any backwash after sutting it down - I do have a homemade spearator though, and its very effective at removing most of the debris prior to getting past the impellor. I can easliy 2/3 fill the separator 10 times (it will fill a 40 gal garbage bag per cleaning) and still only get 5-6 inches of fine dust in the rear bag. So there is only minimal if any dust past the impellor when the upper bag settles post power down.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

No, I didn't see a need for a separator since I mainly resaw and sand, it's all pretty fine. Good point though. This insidious backwash happens only after you turn it off and walk away. It probably is nothing compared to the incidental dust that escapes the drum sander and bandsaw anyway. It just kind of surprised me to see that puff of dusty wind exhaling from my collector at shut down. Multiply that by a dozen times a day and well, it's significant.

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http://www.dickeyguitars.com

If I understand this correctly, you could elminate the problem by replacing the top bag of the dust collector with a cannister filter. The cannister wouldn't deflate when you turn the dust collector off, so there would be no "exhale." I think cannister filters can also do a better job of filtering out the finest dust.

Bill Penz's Web site has some information about this; so does the Wynn Environmental site. Wynn Environmental also sells the filters.

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John Cavanaugh
Saint Paul, MN
"What could possibly go wrong?"

John, I thought of that, but I don't have as yet. You are right, as long as I'm fooling with it, I might as well go filters, it's not all that hard to convert as I understand and the filters are not overly expensive and have more surface area..... hmmmm. Thanks. bd

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http://www.dickeyguitars.com

Whew, those filters are about $150 each, but I'd imagine last a long time...

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http://www.dickeyguitars.com

You could tie a string from the top of the bag up to the ceiling to keep it from colapsing after you turn off the collector.

I spent double what I could've because my collector has a fine dust canister filter on top of it. Very happy 'bout that.

Barry, this thing is huge, it's NINE feet tall and about 32 inches across, single bag below and above. It has a metal rod nine feet tall, but it's the collapse of the bag that displaces all the dust-laden air.

Like Al said a one way valve is not a bad idea. Come to think of it, why not just shut a gate valve and keep the dust from exhausting at all?

Mattia, yes there is always a better mouse trap out there. I bought this one about five years ago and I just don't remember the pleated filter units until more recently? You are fortunate to have avoided this little malady.

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http://www.dickeyguitars.com

Well, in a way, this is exactly what I did, except I ported it through a 12 inches of block, and brick wall, and sealed it with a louvers that open and shut with the exhaust port.

Now, that said, it isn't quiet, but I don't run it late at night, and the dust escape has been minimal. Works like a dream though, and the unit isn't actually "in" the shop area.

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Eagles may soar, but weasels don't get sucked into jet engines.