# Help with dust collector situation



## GPM (Aug 26, 2010)

I have a Jet 1 1/2 hp, 4" dust collector with a 30 gallon cyclone separator in line. I am trying to really tweak it to minimize dust on the table saw and chop saw primarily. I have a good setup for collecting the dust and chips but now have questions about the dust bags and keeping an eye on the pressure in the system.

First, does anyone have experience with upgrading bags to a better bag or canister? I would only do the top bag but would like to get maximum flow to keep the system working at top level.

Second, on my air cleaning system I have a vacuum gauge to show when the filter is getting dirty by showing how much vacuum is present inside the air cleaner main box. I would like to use a gauge on the dust collector but am not sure if it would be more effective to look at the positive pressure on the output side of the blower or the negative vacuum on the input side. I know the two are related but am not sure which one would give me a better/quicker snapshot of the condition of the system.

Any help is appreciated.


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## LeeBarker (Aug 6, 2010)

I like the scientific approach, and will attend to the contributions from this smart community.

Meantime, the low tech discipline requires me occasionally to turn on the system switch momentarily and then, when I can grab a handful of bag (right after I've put on my mask, kids) I just rattle and shake it like a rat terrier treats a stuffed shark, letting all that fine stuff get freed from the walls of the bag and fall down into the barrel. It works, you can see it, and the machine always pulls better after I do that.

But a gauge telling me when to do that would be way cooler.

Also here's a little trick on a DC system: Joints that you think might be leaking? Wrap them with 4" stretch wrap. Stays till you need to take the system apart, nothing gooey involved, and simple.


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## PurpLev (May 30, 2008)

I have the same DC as you. and here is how I upgeaded that useless filter bag:

http://lumberjocks.com/PurpLev/blog/7085

I can't express the HUGE difference between puffs of dust around it while in use, to 0 dust escaping it now.


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## GPM (Aug 26, 2010)

Thanks for the ideas. I am going to install a gauge and when I do I will post it for others. It is not expensive and it is definitely cool.

PurpLev - how do you clean the filter? It seems that 0.3 microns would get clogged up after some time.


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## PurpLev (May 30, 2008)

For now I use an air compressor at low pressure (20-40) and blow at it from the outside all around. I would like at some point to build a paddle that would turn inside, but for now this works, and it's nor as harsh on the filter material.

would like to see a link to your mentioned gauge - sounds like a worthy addition to a DC setup.


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## Dustmite97 (Aug 1, 2009)

30 micron bags are very useless. I have upgraded to a 2 micron filter bag and it is much better.


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## brtech (May 26, 2010)

Yes, 2 micron is better than 30, but the latest research suggests you want to remove less than micron particles. The .5 micron filters (like the Wynn that PurpLev used) do that. There is a fair amount of research on dust in the 1-5 micron range that looks ugly.

Another tip I was surprised to find, but it makes sense: you don't want to clean your filters too much. It turns out that layers of dust is part of the filtering, and if they are too clean, they don't work as advertised.


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## ibewjon (Oct 2, 2010)

i bought the jet filter upgrade [pleated canister] for my north states dc. just measure the diameter to be sure it will fit yours. junk the bag, save your lungs


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## GPM (Aug 26, 2010)

After thinking it through and considering all the options I believe what I am going to do is to simply vent it outside. That is, I am going to replace the top bag with a plenum which has a furnace filter and then vent that air to the outside. This way there is zero chance of that dust being released into the shop.

The couple of issues with this setup are that if you are in a cold climate you are sucking out heated air and will need to replace it. I live in a warm environment so that will not be an issue. The other thing I discovered is to keep some back pressure on the fan so that it doesn't spin too fast. This will be accomplished with the plenum and furnace filter. I can also put a simple HVAC damper in the duct to adjust the back pressure.

Most commercial facilities have the dust collector and bags outside.

Once I have it set up I will send some photos and a report. I hope to have an HVAC guy do some measurements before and after on the system just to see what is what.

Thanks


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## Abbott (May 10, 2009)

I vent my DC unit outside, I love it.


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## GPM (Aug 26, 2010)

Abbot - how did you do the duct work etc? Also, I like your tagline and it is true but one thing I have noticed is that Norm's cuts are so good that it would stay together even if he didn't use any glue or fasteners.


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