Scratching my head about this chute (3-D printed?)

[Packard]

My central dust collection kept the kept the surface of my saw clean until I added a zero clearance insert.

Now I get a small amount of dust accumulating on the table top.

No zero clearance on my dado setup, so that at least remains clean.

 

[ChuckM]

My central dust collection kept the kept the surface of my saw clean until I added a zero clearance insert.

Now I get a small amount of dust accumulating on the table top.

No zero clearance on my dado setup, so that at least remains clean.

I use a ZCI at all times on my SawStop (of course, except the dado insert, which is too expensive to replace) (and Kapex), and that was why I was surprised that with the strip in place, there was no observable dust even when the dust blade guard was lifted up when doing the experiment.

 

[cpw]

The Infinity (labeled Colliflower) ZCI for the Sawstop is much more economical than the actual sawstop ZCI.  You can replace just the inserts instead of the whole thing; so you're only at like $5 a piece.
https://www.infinitytools.com/sawstop-zero-clearance-throat-plate

In the past I used Fastcap Zero clearance tape to extend the life of the Sawstop ZCI or to put on my Dewalt sliding miter saw, but the slight lip from the edge of the tape isn't quite as nice as the Infinity ones.
https://www.amazon.com/FastCap-Clea...4&psc=1&mcid=d0df903341313a46a406e6c86dae3b70

 

[Packard]

I used FastCap’s zero clearance tape on my DeWalt chop saw.  But either my blade has some runout or the spindle’s alignment is not good, because with each cut the opening enlarges until it is no longer effective.

I don’t think the tape is at fault.

 

[ChuckM]

The Infinity (labeled Colliflower) ZCI for the Sawstop is much more economical than the actual sawstop ZCI.  You can replace just the inserts instead of the whole thing; so you're only at like $5 a piece.
https://www.infinitytools.com/sawstop-zero-clearance-throat-plate

In the past I used Fastcap Zero clearance tape to extend the life of the Sawstop ZCI or to put on my Dewalt sliding miter saw, but the slight lip from the edge of the tape isn't quite as nice as the Infinity ones.
https://www.amazon.com/FastCap-Clea...4&psc=1&mcid=d0df903341313a46a406e6c86dae3b70

Yes, those products are very good.

I use Bondo (with no metallic elements) to refresh my SawStop ZCI. The Fastcap ZCI fits the Kapex perfectly, but I don't think it is designed to be used on any table saw ZCIs.

[attachimg=1]      [attachimg=2]

 

[fournierwoodcraft]

My central dust collection kept the kept the surface of my saw clean until I added a zero clearance insert.

Now I get a small amount of dust accumulating on the table top.

No zero clearance on my dado setup, so that at least remains clean.

There might not be enough makup air.  You can add a small hole at the front of the saw curf.

 

[Packard]

My central dust collection kept the kept the surface of my saw clean until I added a zero clearance insert.

Now I get a small amount of dust accumulating on the table top.

No zero clearance on my dado setup, so that at least remains clean.

There might not be enough makup air.  You can add a small hole at the front of the saw curf.

I’ve not heard that before.  It is worth a shot.  I will try it the next time I’m in the shop.  Thanks for the tip.

Packard

 

[ChuckM]

I'm no expert on the makeup air topic, but when the blade is not fully raised in a cut (which is the usual case), shouldn't there be an enough gap at the front to take in air?

 

[ChuckM]

As [member=58818]Mini Me[/member] pointed out, a strip of wood would keep dust spilling from edge cuts to a minimum:

[attachimg=1]  [attachimg=2]
After an hour and a half of continuous trimming, the shop's air quality remained good (under 4; over 12 is fair)), even though the air filtration system was not turned on.

Someone had this to get rid of...I took about 1/10 of it for an upcoming project (before me, some guy took away a truck load of the pile already):
[attachimg=3]

[scared] [scared] [scared] (as feared by the SawStop):
[attachimg=4]

The last preparation step will be planing them to final thickness.

Edit: Planing completed this morning (see middle piece):

[attachimg=5]

 

[woodferret]

I'm no expert on the makeup air topic, but when the blade is not fully raised in a cut (which is the usual case), shouldn't there be an enough gap at the front to take in air?

Still typically not enough.  Hooked on Wood has a ZCI rebuild video


He was pretty thorough at drilling holes and testing things before settling on the final design of left and front holes.

 

[ChuckM]

I'm no expert on the makeup air topic, but when the blade is not fully raised in a cut (which is the usual case), shouldn't there be an enough gap at the front to take in air?

Still typically not enough. 
Snip.

I was responding to this suggestion: "There might not be enough makup air.  You can add a small hole at the front of the saw curf."

If the gap in front of the blade on the ZCI was insufficient, I doubt that adding a small hole would make much a difference.

I haven't watched the YouTube video you linked, but that ZCI design wouldn't help me when I rip boards that are wide enough to cover all the holes. In any case, my SawStop dust collection blade guard is over 99% effective in practice -- after the guard tube is connected to a shop vac directly (the manufacturer's claimed effectiveness is 99%) except when doing edge cuts or cross cuts used with the miter gauge. For edge cuts, as explained above, a strip of wood will solve the problem.

Non-SawStop dust collection blade guard users might look into that particular ZCI design further.

 

[Mini Me]

The ZCI is covered by the material being cut either partially or wholly and air therefore makeup air cannot enter through the ZCI no matter how many holes it has if those holes are blocked. The overhead guard is not blocked and air will enter as long as it does not seal on the material's top face. I think I made this point when that video was first posted.

 

[ChuckM]

Anyone who thinks a re-designed zci would significantly help their table saw's dust collection is not focusing on the most important things. In the grand scheme of things, the standard zci design is fine. If you think a new ZCI is the magic bullet, you'll be disappointed.

What people should look into is the overheard dust collection (just ask anyone who has the SawStop dust collection blade guard (connected to a CT15 or shop vac)) and the power/source of their suction/ dust collectors.

 

[rst]

I fab more plastics than wood, so anyone that has cut acrylics, ABS and other plastics knows what a static mess they make.  I have a forties era Delta that has an enclosed blade and intragal dust chute.  I bought, years ago, an over arm collector from Penn State Ind. as it was reasonably cheap I did not look like the supplied blade cover so made my own with 1/2” acrylic and used 4” National Guard Products 4” brush for the sides.  With separate Fein vacs attached to the dust chute and overarm cover collectors, I remove 90% of chips.

 

[ChuckM]

Start viewing at 0:55 or so -


What makes the SawStop dust collection blade guard unique and effective is the lateral sides which keep dust inside the guard allowing the suction to do its work. The guard itself is shaped to harness the momentum of the spinning blade to aerodynamically channel dust to the tube/dust port or hose in the case of setup shown in the video. It is more than just a suction opening over the blade. It isn't cheap: $222 Cdn, but used properly in conjunction with the under-the-table dust collection in a PCS or an ICS, you get close to dust-free ripping.

In general, I now don't wear a mask using the SS PCS.

 

[Mini Me]

What I have seen done as proof of concept of overhead guard dust collection is tufts of wool taped to the inner surface of the guard so the airflow can be seen. All this and more can be seen on the Dust Extraction sub forum on the Australian WW forum. There is enough information there to keep someone busy for a month reading it and a large part of it is founded on good physics or proven testing. It holds the world's best source of proven dust extraction in the world bar none.
https://www.woodworkforums.com/f200

 

[ChuckM]

Anyone with a typical hobby shop who is mulling over the topic of over-the-table dust collection should think twice before acquiring the overarm blade cover type of dust collection system:
https://www.lumberjocks.com/threads...gned-hood-no-better-than-the-standard.324168/

I use the SawStop dust collection blade guard at home (1 HP DC & shop vac) and worked with the Excalibur overarm blade over system at work (until five years ago). Even with a more powerful dust collector (5HP but running in a pipe system) at work, the overarm system performance was dismal compared to my dust collection blade guard.

In terms of price, effectiveness and ease of use, the overarm blade cover is a let-down vs the dust collection blade guard. I wonder why there isn't a third-party kind of dust collection blade guard product for non-SawStop saws.

 

[Mini Me]

These ar some of the reasons an overhead guard does not work well

A dust extractor that does not have enough air flow

The ducting is too small to support the required air flow

Poor hood design 

Believe me or not but all this stuff has been worked out and all the answers are available in the link I posted complete with pictures and reasoning and taking the information and applying it to your own situation.

 

[ChuckM]

As [member=58818]Mini Me[/member] pointed out, a strip of wood would keep dust spilling from edge cuts to a minimum:

[attachimg=1]  [attachimg=2]
After an hour and a half of continuous trimming, the shop's air quality remained good (under 4; over 12 is fair)), even though the air filtration system was not turned on.
Snip

I was using the same strip method (post #28) to reduce dust spilling from edge cuts, but half way through, it didn't work well as in the past. The culprit was found to be a blockage in the SawStop dust blade guard.

[attachimg=1]

Luckily, I could simply pull the pivot pin out and clear the blockage without upsetting the fence setting. I had close to 200 edge cuts to make and this happened twice during the session.

 

[fournierwoodcraft]

I noticed you are using the magswitch.  There are dust fittings that work with the magswich.  For this exact scenario.