SawStop Table Insert Plate Gets a Little Lift

[Thomas Wilson]

I am still discovering little things that aren’t in the SawStop Floating Overarm Guard manual. Today’s lesson is that the suction from a strong dust collector through the guard can lift the insert plate. It lifts it as high as the locking mechanism allows it to travel. It lifts about an 1/8” which is enough to snag a workpiece being fed in. The easy fix is to start with the workpiece on top of the plate holding it down. Without the lock, I suppose the air flow could pull the plate out of the table. I did have air flow connected to the blade shroud below the table. Apparently, gaps between the shroud and the bottom of the table are large enough to reduce suction on the bottom of the plate to a negligible level.

Here is short video showing the lift. Turn sound on so you can hear the dust collector spinning up and then down.
https://www.youtube.com/shorts/YP89fAB-zm8

Also, the air flow can suck small cut-off pieces back toward the air hose at the rear of the guard. They can be pulled into the rear of the blade and flung forward with great force. I have had this happen twice. The first was when I was trimming a rough 8/4 oak board to width. The width varied such that at times the cut was less than a blade width and at times a thin sliver was cut off. One of these slivers was caught and thrown out the front of the guard and hit my hand. My hand was at least 6” in front of the guard and more than 11” from the blade. The impact was enough to draw blood and make me consider ways to be safer. One is to put my magnetic feather board in front of my hand to deflect any projectiles. Another is to sacrifice some dust collection and throttle back the flow by closing the blast gate a bit. A third is to use the bandsaw. My bandsaw has a small table and is not well set up for ripping long heavy stock.

The second incident was when I was cutting 1/16” x 3/4” strips into short pieces to use for checking blade projection on hand planes. One piece was sucked into the dust collector and another was throw forward violently but harmlessly into some dark corner of the shop. I switched to the bandsaw at that point.

[Scott Clausen]

Why not place a small inlet on the over arm hose to reduce the suction a little or leave a blast gate open a little.

[Thomas Wilson]

Why not place a small inlet on the over arm hose to reduce the suction a little or leave a blast gate open a little.

Yes. Either of these would reduce the suction and the air flow through the guard as would the things I mentioned. The point really is that dust collection gurus have advocated for more and more air flow to collect more fine dust, but the increased flow can introduce other problems and hazards to be aware of. I am just trying to do that.

[Frank Pratt]

Switch to the standard dust collection guard. It provides near 100% dust capture and doesn't lift the plate at all.

[Thomas Wilson]

Switch to the standard dust collection guard. It provides near 100% dust capture and doesn't lift the plate at all.

I bought the floating guard with the initial SawStop purchase but the standard guard came with the saw too. I have intended to try the standard for comparison but haven’t yet. The smaller area of the standard guard against the table would not lift the insert as easily, nor would small parts be lifted and blown into the blade as easily. It has some other good design features. For example, I like the pivoting side shields for capturing dust from cuts on the edge of the work piece. The drawback I have heard is that it does not get enough air flow for good fine dust collection unless it is connected separately from the main dust collector to a powerful shop vacuum. Maybe less flow/less dust collection is just better for preventing lifting and kickback. How is your guard connected?

I will try the standard guard next week in a couple of configurations. This week, I am hanging close to Janicewhokeepsmehumble. She had cataract surgery on Monday. I have about 500 bd ft of rough 8/4 and 4/4 white oak to mill. I should be able to develop a good opinion of what works for me. Originally, my emphasis was to achieve good collection of fine dust. There are other constraints to consider.

[Frank Pratt]

I have a 2.5" flex that drops down from an overhead duct to the blade guard. According to the particle counter, dust collection from the saw is 100%. The only time guard lets anything out is when cutting less than a kerf width from the edge of a board. Then a plume of sawdust squirts out the side of the guard. This is a characteristic common to most any guard though.

The overarm pipe that SawStop sells to connect to the guard is pretty universally panned because: a) the pipe gets in the way, b) the pipe is way too restrictive, and c) the connection to the cabinet port doesn't pull enough airflow. The flex I use doesn't move air like a shop vac would, but it's plenty to catch all the dust.

[Alan Lightstone]

What dust collector / HP are you using? I'm not seeing any of that with mine, using a 5hp Oneida DC.

[Thomas Wilson]

What dust collector / HP are you using? I'm not seeing any of that with mine, using a 5hp Oneida DC.

Same as you I think, Oneida Dust Gorilla Pro with Smart Boost, 5hp. It may be a difference in plumbing. My wye for the table saw comes straight up through the floor into the floating guard with the lateral going to the cabinet coming off at 30 degrees with a 60 elbow, into 40” of flex, and then into a 90 degree elbow into the saw’s dust port.

It also may be that my filter is newer.

The dust system is new for me and I have no significant prior experience with dust collection. A lot of what I report is just the newby effect.

[Alan Lightstone]

I have modified mine, as I was having issues with dust collection on some thicker woods. I essentially built a CNC dust boot brush around it. It very much helps with dust collection, though does limit visibility. Still have to find adhesive that more permanently attaches it, but it has helped a lot with dust collection. Seems like the opposite problem that you have, but would fix your problem.
Sawstop Floating Arm Dust Collection Skirt.jpg

I'll be the first to admit that my routing of dust collection ducts is probably not optimal (a few wyes before it ever gets to my table saw), and this very much helped with the problem. So my particular setup is clearly not suffering from too much suction. I just don't see your particular problem at all.

My ducting is for a 6" duct, split into a 4" duct for the main SawStop DC outlet, and an additional 4" duct split by a wye into a 4" duct for my router table, and a 4" duct for the SawStop Overarm Dust Collector. Each has its own gate.

How is yours routed? You must be getting significantly more suction at the overarm part than I am. Is that coming at the expense of suction at your main SawStop DC port? I have a blast gate on my overarm dust collector, as you don't use it for every cut. Do you?

[Thomas Wilson]

Hi Alan,

The brushes would be the difference I think. My guard was resting directly on the table. I think the brushes must let more air into the guard raising the pressure and reducing the lift. Also, I let my guard float, i.e. I do not lock the parallelogram. The guard gets sucked down to the table. I will check the pressure under the guard using a Testo pressure gauge when I get back to the shop on Tuesday. Do you have a way to check pressure under the guard?

[Alan Lightstone]

Hi Alan,
I will check the pressure under the guard using a Testo pressure gauge when I get back to the shop on Tuesday. Do you have a way to check pressure under the guard?

No, I don't have a way to measure pressure.
Why don't you fix the guard height a slight amount over your board instead of letting it float? I would think that would solve your issue by slightly decreasing the suction on the floating guard.

Also, might there be a reason why the main DC suction is decreased on your SawStop? In other words, the zero clearance plate is not being sucked down as hard as it should.