In a day or so I will take delivery of my new SawStop tablesaw. Having studied the material on Bill Pentz’s website, I would like to provide enough air movement to collect the fine sawdust. I have a 6″ drop for the saw, but the machine comes with a 4″ port.
Inside the cabinet the 4″ port connects to flex hose leading to the iron shroud around the blade. In theory, this will improve the collection efficiency by creating a higher air velocity at the blade.
As I see it now, I have several options. One is to collect with only the 4″ line. Another is to split 6″ into two 4″ lines and somehow direct one of them to the clear plastic guard above the table. Yet another is to direct the second 4″ line into the base of the cabinet.
That last option doubles the airflow through the cabinet, but will it defeat the blade shroud? Will it help? Is it neutral?
Connecting to the guard is ideal when the guard is on, but the benefit is lost when using only the riving knife. And connecting air to the guard may be a picky procedure.
I am grateful for any constructive input from the community here.
Bill
Replies
I just hook up a 4" flex hose to the rear port. That's more than adequate for dust collection IMHO. Yes, you could try to hook up the DC to the guard, but I don't think it would pick up enough to be worth the trouble.
I respectfully disagree.
I've had a dust collector hooked up to the 4 inch port on my tablesaw for a year or so now. And while it does a fine job of collecting chips under the cabinet, without an additional collection site on the blade guard, a lot of dust gets thrown off the blade, into my face, and into the air as I cut. I consider it worthwhile to have this additional blade guard collection port in place, even though it can seem like a minor hassle at times.
You're right that with the blade guard removed, the dust collection port on the blade guard is lost. But for the remainder of the time, especially when ripping, it seems like a good idea to collect all the debris you can.
You can accomplish this in a couple of ways. One easy method would be to plug a Y fitting into the 4 inch hose and take off from there with a smaller hose to the blade guard. Penn State Industries sells an after-market blade guard with a 2 1/2 inch dust port on top for about 25 bucks. I modified the blade guard that came with my saw (Grizzly) to accept a 1 1/4 inch hose from a Shop Vac. Right now I've actually got it hooked up to a shop vac, but will add a port as described above when I get my cyclone in place.
Since you've got a 6 inch pipe going to the saw, you could take off from that with a Y fitting to a shop vac hose (2 1/2 or 1 1/4). Those bigger fittings are pretty pricey though, so the 4 inch port would probably be more economical.
ZoltonIf you see a possum running around in here, kill it. It's not a pet. - Jackie Moon
"I don't think it would pick up enough to be worth the trouble." I'm with Zolton on this -- it's important to collect as much as that stream as you can. It's coming right off the blade and right into your breathing space. Whatever you can do to keep that fine dust out of your lungs is "worth the trouble."forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Thanks to all who have responded so far. I am curious how much better the collection on a SawStop is with only one 4" line than, say, a PM66 or Unisaw, neither or which have the internal blade shroud.My old Unisaw had a right-sloping cabinet floor leading to a rectangular slit that was of the same cross-sectional area as a 5" round duct. They also made and sold a transition fitting to 5" round as an accessory (Delta only did this in the early 90's, as far as I know.) It collected better than any 4" setup I've ever seen. For a time I had it fitted with the Excalibur overarm guard with D/C, but I got rid of that because it was too fiddly and too often in the way of regular operations.Because of my experience with the Excalibur, my main objective is to get the best collection I can get from below the table. Top collection is icing on the cake, but I already know it will often be defeated so I don't want to depend too much upon it.Powerfed ripping, dadoing, rabbeting, tenoning...all of these operations require good collection from below, so that is my prime objective.Bill
I am not sure about a PM66 or Unisaw but my General 350 is basically the same design. It does not have a blade shroud but there is a sheet metal ramp in the base angled toward the 4-inch dust port. It is currently hooked up to a 2 hp Grizzly dust collector with 8 ft of flex hose. There is no collection at the blade guard. It does a good job but sawdust accumulates in the saw base. To clean it out I take the blade insert out and point the out hose of a shop vac in the blade opening with the duct collector (not the saw) running, cleans it out in a few seconds.
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I wonder if there is not enough airflow through the blade insert to keep the sawdust moving. The top fits fairly close to the base so there is little airflow into the cabinet except through the blade insert. I am getting ready to upgrade the duct collection system and I am thinking of enlarging the 4-inch port to a 6-inch port but I am not sure it will do any good if there is not enough air moving past the saw blade. This is especially true using a zero clearance insert. I have also thought about opening an input port in the saw base on the upper and opposite side of the collection port to introduce a cross draft and more airflow. I am not sure if it would help or not.
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I don’t think dust sitting in the cabinet hurts anything. It is trapped and not floating in the air to breathe or get into my finish. Maybe ill leave good enough alone and add some collection to the blade guard with the new system.
Bob T.
Bill, all I was trying to say in my post was that the DC is very good on the SawStop. Whether or not it is better than other saws I wouldn't know. I use the blade guard on my SawStop as much as possible and it keeps most of the above table dust out of my face.As to the other replies about the above table dust collection, I have a different prospective on all this DC frenzy. Yes, it is important to get as much of the fine dust as possible, but to I'm also a very practical person just trying to do woodworking as a hobby. While Bill Whats Hisname has a site extolling all the needs for dust collection on our equipment those of us who are not out in the shop for long hours day after day aren't exposed to as much sawdust as a professional. No I'm not interested in seeing more data. The bottom line in all this is to get the best dust collection possible for your situation and budget. Meanwhile back to the OP. SawStop has provided excellent below table dust collection on its saw. You will like what they have done. A good DC attached to the 4" port on the rear of the saw, not a vacuum is the best way to go. If you want to add DC to the guard I've seen several posts here and elsewhere that show how to do it. That may require a different guard, but I did see a post somewhere that showed a guard with DC that was a replacement of the "stock" SawStop guard. I don't remember if he used a Shark Guard or some other brand. Shark Guard does make one for the SawStop http://www.leestyron.com/sharksawstop.php. Something like this http://www.woodcentral.com/bparticles/overarm_guard.shtml would work too.
Edited 3/27/2008 1:33 pm ET by basset-hound
Basset-hound,Thanks for your reply, and the link to the Shark Guard. That is the sort of thing I am interested in seeing.When the saw arrives I will likely hook it up to a 4" line just to assess how well it works. I don't want to overthink this, but it is what I do for a living, so the exposure issue is significant for me.I am very curious to know if anyone has added more that a single 4" line sucking from beneath the table on a SawStop and what their results may have been from doing that. The great thing about forums like Knots is that we can learn from and build upon the efforts of others. It beats having to make all the possible mistakes every single time.Bill
bill,
I'm just curious, with all the engineering that went into that Saw Stop, have you contacted them for any aftermarket recommendations?
No, I have not contacted SawStop about this. First I want to take delivery of the machine and carefully go over it.My experience with OEM's is that they are usually not the real experts on ancillary concerns such as dust collection. If they were, then we would see far better designs on the machines sold new.I suspect that the system used on the SawStop saws is superior to what is found on most USA cabinet saws. What I do not know is if it is good enough, and what is my best option for improvement if the answer is "not good enough."Bill
Congratulations on your purchase! I've had mine for a month now and I love it! Be ready, the saw is heavy!
I have a 1.5 HP Jet Canister collector, rated at 1100 cfm, running a 6" tube - 10 ft - reduced to 4", at the saw. The below cabinet collection is pretty darn good as long as you remember to close the little access panel, inside the cabinet. If you don't, you will end up with a cabinet full of dust.
As for the stock blade cover - I'm not sure if you can modify the existing blade cover to work with a collector - at least in a way that doesn't block your outfeed... yet provides enough CFM at the blade. Personally, I think I will go for an aftermarket blade guard that has a DC hookup - when I can afford it.
Cheers!
Edited 3/27/2008 11:24 am ET by Tbagn
Bill,
In dust collection, large airflow moving at low velocity picks up the dust (relatively light) and moves it to the collector.Optimally, you need the airflow moving over the blade at the point of dust creation to capture it... as long as you're using a separator (cyclone, secondary or other) or take good care of the filter and final collecter (to keep the airflow moving), a single 4" port should do a good job for you.
If you add a second port to the cabinet, and there's sufficent air intake, you'll improve the result, but not by much...you'll just catch more of the dust escaping your first port, as the first port will pull in all the air it can.
I think 4" is enough air, but if you want to improve capture at the port, you'll need to increase the velocity (vacuum power), at the point of collection; you can only do that by adding a second stage to your system...(two fans in series)
Steve,Yes, I realize that a second port will only get the dust that the primary port misses. That is the only dust I am concerned with in my original posting. What I question is the most auspicious location for that second port, and how will it affect the airflow at the primary port.I have the available airflow, as the saw sits 10 feet from a 5HP cyclone, with a 6" branch off the 8" trunk line dedicated for the saw. Currently no plans to convert my fan into a turbine!Bill
OK then..consider this...Both ports, as long as they are the same size and length, branching off the main trunk at the same place (a branch Y will accomplish this), will pull the same air...therefore, as long as both ports can pull the same complement of air, one port will not affect the effeciency of the other port.
If however, less than the required amount of makeup air is available in the cabinet, the effeciency of the first port will be reduced by the addition of a second port; the effeciency is affected least at the port closest to the air source; although the more affected port will create a negative pressure in the space, so both ports will suffer; the system will try to balance itself.
To minimize this, you could introduce a second port of smaller diameter; inflow area should equal port area...Since your saw has a 4" collection port, I'm going to assume the input area, probably around the blade, is st least equal to Pi(r2)4.
Assuming you can get enough makeup air into the cabinet, I'd place the second port at the bottom of the cabinet, and try to get makeup air to move accross the bottom, "Sweeping" up the dust missed by the primary port.... or you might consider getting the air to move accross the motor.... even though it's probably a TEFC motor, it can't hurt to have some airflow accross the motor housing.
Steve,
Based on what you say, I'm wondering if our zero clearance plates have a negative impact on dust capture?
Zero clearance plates are a double edged sword... the reduced clearance helps keep the dust from escaping the cabinet IF the dust leaved the gullets ... they also reduce the available makeup air...Typically, the angle adjustment and the louvres on the door provide enough air in general...but the placment of those openings are not ideal, and dust typically collects in the corners and on the adjusting worm screws..some day someone will adress this issue.
IF the dust does not leave the gullets... you'll eat some (as I do)
Steve,
I'm not overly concerned about the dust that is missed, I'm enjoying the clean air in the shop too much. I may play around a bit with thin kerf blades and non-zero plates just to see...thanks
OK...good luck.
Steve,Thanks for that. I recall the SawStop cabinet as having some air inlet louvers on the side. When my saw arrives I'll attempt to measure and sum all the inlets' areas prior to making any modifications.When sawing wide wood or sheet goods, very little air can get in from the top of the table, as inlets are covered by the workpiece being sawn.I agree that the place to put a second port is near the cabinet floor to get the dust that is missed and puffs out of the blade shroud.Bill
Saw stop dust collection
Well, I'm unimpressed. I just purchased the $199 dust collection offered by saw stop, and dealt with a very easy assembly. Everything fits nicely, and it's very pretty. Black with the saw stop logo in several places. The only problem is that there's not much suction. I have plenty of air flow at the machine, I'm using a clear vue cyclone with 6" pipe throughout the shop so that's not the problem. And the collection of chips and dust below the table is quite good. As I see it there are several problems: 1) the main DC port is only 4", it should be 6" according to Bill Pentz, 2) the adapter provided is basically a T, not a Y, 3) the pipe in the overhead system is too small, and 4) the flex pipe they sent is ribbed on the inside. All of these things contribute to a lackluster performance in my opinion. Perhaps my expectations are too high, but quite a but of fine stuff winds up on the table in front of the blade. In summary, I wouldn't recommend it to anyone. It's just OK, but definitely not worth $199. I'm also curious to see if anyone from Saw Stop will monitor this forum and respond. It's a really good saw, but the accessories leave me unimpressed.
It's interesting that there have not been any comments for 8 years. Either everyone has quit trying to upgrade the dust collection system or just given up trying to get a response from SawStop. I have to agree with the last poet by Isujazz, I have owned and used several tablesaws in my time but have never experienced the amount of dust that comes off of this machine. Don't get me wrong I think the saw and safety of it are great but the Dust Collection System are absolutely the worst of any saw I've owned.
Like the comments above I have tried to upgrade the system, to no avail.
I purchased the 4" overhead attachment but it barely removes any of the small particles that come off the back of the blade and minimally removes the dust from inside of the cabinet. It requires the removal of the inspection plate and getting in there with the vacuum hose and attachment to empty it, after which I vacuum up all the particles that are that are thrown onto the floor over my shoulder.
Does anyone know of an upgrade that could help?
Hopefully SawStop sees these posts and works on a fix! as I said, this has to be the worst system ever.
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