Over the blade dust collection

[Rod Sheridan]

Completed Installation.jpgB3 004.jpgHi, I have both a riving knife mounted over head dust collection guard and an overarm type.

The overarm is great for non through cuts such as dado or rebate, the riving knife guard will function well with a sled if the sled fence is low enough.

The riving knife guard will work with a shop vac due to low area, the overarm will require connection to a dust collector.

Marshall, you're certainly correct on how nice it is to have over head collection at the blade...............Regards, Rod.

[Mike Kees]

I have used both a sharkguard and the Excalibur overhead. I am not sure how the overhead will work with a crosscut box if you lift it high enough for clearance of the box. (will it still capture most of the dust.) The sharkguard captures dust very well,but wont work with the crosscut box or dados. The answer is of course buy a sliding tablesaw. Just kidding,it was my solution though. I remember a fine woodworking article I think, Kelly Mehler or something where he made crosscut boxes with a lexan safety guard in the center. Something like that with a dust port attached is going to be what you need. Good luck,Mike.

[Don Kondra]

Here's an inexpensive solution, Full thread here

The metal duct is high enough I can still use my sled.

4 - Front three quarter.jpg

I've since added a brush, ordered overseas for less than $10 shipping included

The brush is attached with Velcro so I can remove parts if necessary.

Brush front.jpg

To set the width of cut, etc. the whole contraption swings out of the way !

Brush turned.jpg

Cheers, Don

[Jacques Gagnon]

Nice work Don!

[Doug Garson]

Agreed, Brian, about turning on both a DC and a shop vac just to cut a board. It's annoying.

Not if you have the power switches set up like I have, they are attached to my overarm assembly by magnets and I can reach both of them and the power switch on my saw without taking a step. And you would be surprised at how well it works for almost no cost.

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[Mark Carlson]

I have a shark guard and the excalibur. I prefer the shark guard because it forces me to use a spliter does a better job of dust collection and offers a less restricted view of the cut. I dont like the boom arm of the excalibur or the size of the guard. I also use a jessem slider, so dont need a cross cut sled, and the shark guard works well with the slider.

[marty fretheim]

Hey Brian, Ive got a slider similar to Rods. I tried a zero clearance insert and the below table dust collection became non existent, so i ditched it. I have an Oneida 5hp DC, I use the splitter mounted overhead guard like Rods and without the ZC insert I get great dust collection. I'm positive your DC set-up is plenty, no need for a shop vac. I also believe Clearvue gave you good advice on hose size. What I don't know is if your cross-cut sled will act as a ZC insert and require the overhead DC to do all the work, and in my experience they just can't. Maybe the larger boom arm type collector/gaurd would do a better job.

If you have to raise it up high enough for the sled to pass under its not likely to do much good. Thats just my experience for what its worth.

Marty

[John K Jordan]

I have a Grizzly G0691. My DC is a Clearvue 1800 cyclone. With the wide factory insert dust collection is great! I finally installed my zero clearance insert and built a cross cut sled. With the sled, my dust collection is terrible. I have dust flying off the top of the blade. I have begun to research a solution....

I have the 5hp CV1800 and have an Excalibur not yet installed (PM66 with a sliding table). I was told a 6" duct to the saw cabinet with a wye to feed a 4" to the overarm would work best. The beast of a DC seems to have an excess of suction!

I've wondered about the poor dust collection with a zero clearance insert - it seems like it must restrict the air intake enough that the air flow inside the cabinet is choked. I had an idea I want to try to increase the airflow near the blade: bring in a short piece of PVC pipe (2", 4"?) from outside the right side of the cabinet and position it close to the blade, perhaps on the downside (front). The end outside the cabinet would not be connected to anything, just open to the air. My theory is the vacuum in the cabinet will pull air through the PVC pipe and maybe create enough air movement to "blow" the dust out of the blade gullets so it can be pulled out by the 6" duct, something the wide opening in the factory insert probably does.

Any positive air duct would have to consider the blade height and tilt adjustments. I haven't taken a close look at this yet with an engineering eye but plan to. I can't see how extra air intake there would hurt anything but it would be easy enough to remove and patch the hole if it didn't work out. Has something like this been tried before?

JKJ

[Pete Janke]

Watching this closely as I am looking also. I thought about the one from SawStop but since my saw isn't a SS I'm not sure if it will work with my saw.

It will work fine. It was a simple retrofit to attach the SawStop blade cover to the Grizzly splitter on my G091. Just a couple of screws. I run a 4" dust collection hose from the ceiling to the blade cover. I still get a little saw dust, depending on the cut, but it is way better than no over the table dust collection at all.

[Jerome Sidley]

Watching this closely as I am looking also. I thought about the one from SawStop but since my saw isn't a SS I'm not sure if it will work with my saw.

I have the saw stop and it sucks well not really I get dust everywhere. I am planning to upgrade to something with a 2" hose where there will be some airflow.

[Osvaldo Cristo]

I have the 5hp CV1800 and have an Excalibur not yet installed (PM66 with a sliding table). I was told a 6" duct to the saw cabinet with a wye to feed a 4" to the overarm would work best. The beast of a DC seems to have an excess of suction!

I've wondered about the poor dust collection with a zero clearance insert - it seems like it must restrict the air intake enough that the air flow inside the cabinet is choked. I had an idea I want to try to increase the airflow near the blade: bring in a short piece of PVC pipe (2", 4"?) from outside the right side of the cabinet and position it close to the blade, perhaps on the downside (front). The end outside the cabinet would not be connected to anything, just open to the air. My theory is the vacuum in the cabinet will pull air through the PVC pipe and maybe create enough air movement to "blow" the dust out of the blade gullets so it can be pulled out by the 6" duct, something the wide opening in the factory insert probably does.

Any positive air duct would have to consider the blade height and tilt adjustments. I haven't taken a close look at this yet with an engineering eye but plan to. I can't see how extra air intake there would hurt anything but it would be easy enough to remove and patch the hole if it didn't work out. Has something like this been tried before?

JKJ

I share your idea. DC works with high volume but low negative pressure. Your idea makes lot of sense. Pls let us know your results when you can do that.

All the best.

[Marshall Harrison]

Thanks for that info Pete and Jerome. Kind of money strapped at the moment so plenty of time to figure this out.

John, it seems an easy way to check out your theory would be to just crack open the motor cover on your saw as that would let extra air into the cabinet.

[Nick Decker]

JKJ,

Not sure how it would affect your problem (Too much suction? A totally foreign concept, to me.) but I've wondered about drilling some holes in my ZCI, left and right of the blade slot. I've seen a picture of that somewhere, but no explanation of how well it worked. Don't see how it could hurt, but I'm open to anyone's thoughts.

[Nick Decker]

The problem with my SawStop PCS, and maybe it's like this on all cabinet saws, is that there is no semblance of sealing the various openings in the cabinet. It just relies on an open channel to direct sawdust into a 4" hose that twists around and exits the rear of the cabinet, where it attaches to the DC.

[Brian Behrens]

Thanks for all the replies so far.

I don't have a problem collecting inside the cabinet, even with the zci installed. I see videos all the time of saw cabinets full of dust, with people saying "the dust only gets up to this level and stays that way". Well, with my clearvue, there is literally NO dust in the cabinet AT ALL.

I think the problem with the zci is that it takes away the path for a downdraft from above the table. With my factory insert installed, I can throw a handful of saw dust on the table about 6" from the blade and it gets sucked down through the insert. With the zci, it has to be much closer.