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(01-07-2021, 09:32 AM)Philip1231 Wrote: I have found that the SS dust collector shroud works better with a shop vac: pic of hookup using ordinary SCH 40 PVC elbow and a few misc. fittings:
That doesn't come as much of a surprise to me. Depending on what DC the shop vac is being compared to, the shop vac may actually move more air through that little hose. They're designed for high static pressure to move air through small hoses at high speeds, and some have max SP's approaching 100" WC, though I suspect most are in the 50-60" range. My "2 hp HF DC" peaks out at around 10" SP, though it obviously moves a lot more air at low pressure than my Rigid vac. But connect my FrankenCyclone to a shop vac hose, and not much moves through the hose; certainly not as much as my Rigid vacuum will pull.
OP: High SP alone doesn't mean a vac will move more air than a big blower, as it depends also on the big blower (large blower wheel almost always means higher max SP compared to a smaller DC blower) and what they're connected to, but it's worth testing at the very least. Clearly Philip1231 is getting good results.
Tom
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01-08-2021, 11:11 AM
(This post was last modified: 01-08-2021, 11:19 AM by Handplanesandmore.)
(01-08-2021, 10:10 AM)TDKPE Wrote: That doesn't come as much of a surprise to me. Depending on what DC the shop vac is being compared to, the shop vac may actually move more air through that little hose. They're designed for high static pressure to move air through small hoses at high speeds, and some have max SP's approaching 100" WC, though I suspect most are in the 50-60" range. My "2 hp HF DC" peaks out at around 10" SP, though it obviously moves a lot more air at low pressure than my Rigid vac. But connect my FrankenCyclone to a shop vac hose, and not much moves through the hose; certainly not as much as my Rigid vacuum will pull.
OP: High SP alone doesn't mean a vac will move more air than a big blower, as it depends also on the big blower (large blower wheel almost always means higher max SP compared to a smaller DC blower) and what they're connected to, but it's worth testing at the very least. Clearly Philip1231 is getting good results.
On the design seen in Philip's photo, the only thing I'd change is the tip of the hose. That part seems to be narrower than both the hose and the elbow connector. If so, I'd try to find a solution so there's no narrowing there. I'd cut off the hose at the rubber connector and connect the bare hose to the elbow directly. The idea is to increase the amount of dust that can be extracted.
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Isn't that elbow just slipped over the SS guard???
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(01-08-2021, 11:14 AM)fredhargis Wrote: Isn't that elbow just slipped over the SS guard??? It is possible that the decreased pressure increase velocity rule applies here. I will take a wait and see approach. I think I will connect my overhead dust collection to a shop vac. I do have a cyclone separator for a shop vac.
Tom
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(01-09-2021, 07:38 PM)tablesawtom Wrote: It is possible that the decreased pressure increase velocity rule applies here. I will take a wait and see approach. I think I will connect my overhead dust collection to a shop vac. I do have a cyclone separator for a shop vac.
Tom
Do you see a difference in the cyclone vs. the shop vac?
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(01-09-2021, 09:45 PM)AztecKing Wrote: Do you see a difference in the cyclone vs. the shop vac?
I notice that the separator separates the chips on a router table from the finer dust and my filter lasts longer in between cleanings. I have the Rockler version, and not the Dust Deputy. I do not know about over the blade collection because I do not have any. Someone said he thought in looked like a narrowing because of fitting in a picture and I said it might be a blessing It could work like a Ventura on a carburetor or an air ejector on a steam powered ship. decrease pressure increase velocity and velocity is how a shop vac works.
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01-10-2021, 07:30 PM
(This post was last modified: 01-10-2021, 07:31 PM by Handplanesandmore.)
(01-10-2021, 03:38 PM)tablesawtom Wrote: thought in looked like a narrowing because of fitting in a picture and I said it might be a blessing It could work like a Ventura on a carburetor or an air ejector on a steam powered ship. decrease pressure increase velocity and velocity is how a shop vac works.
Tom
The narrowing isn't a blessing here because while it increases the suction, it cuts down the amount of dust that can go through. The end result could be that some dust from the blade is not caught fast enough, spilling over into the air. At least that's how it was explained to me in a group presentation by a representative from a dust collector manufacturer. He compared it to using a straw to suck out water from an overflowing tank.
Simon
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(01-10-2021, 03:38 PM)tablesawtom Wrote: decrease pressure increase velocity and velocity is how a shop vac works.
It does work like that, but at the tool. Fast moving air drags dirt/dust that’s sitting on a surface or buried in carpet into the air stream. The rest of the trip is just transportation.
With a dust collector, the object is to move a lot of air so you get a fast-moving air stream over a wide area, so the dust being tossed free of the cutter/blade at high speed can’t escape that air flow. The tighter you control the escape route (smaller area), the less air you have to move, but even with good duct collection shrouding, you still have a lot of area you need to pull air through. So you need a big blower, and to keep the air flow up, big hoses and ducts to keep the restriction down.
So yeah, they work the same way as far as moving the air at high enough speed to capture or prevent the escape of dust and chips, but it isn’t the speed of the air in the hose that’s relevant - it’s the speed of the air around and into the shroud or any escape routes, like the curved slot the blade elevation wheel shaft passes through on a TS. Or the space around the blade on a saw with a good ducted blade shroud, like the SS has.
Tom
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(01-06-2021, 07:01 PM)AztecKing Wrote: I'm getting ready to order a new Saw Stop Professional table saw with the 3 horsepower motor. I do have some questions about the dust collection system and the mobility kit and which one to order. I'm also wondering if there's any other tips that I should be aware of before I placed this order?
Jeff
I offer a comment concerning the industrial mobile base.
first follow the direction about removing the saw from the box etc. . . . .
Place the immovable saw in your garage in your wife's parking place.
add the cast iron wings to the top, the fence rails . . . .
then get to the part where the saw stop assembly instruction says 'call your four strongest friends to help lift the (now heavy) saw onto the base'
totally out of the blue you need 4 gorillas while what is now a boat anchor sits in your wife's parking place
Not my idea of quality customer relations. A warning on page one that assistance will be needed would have been helpful before weight was added to the saw. I was 4 gorillas short when I placed the saw on the IMB. With this one glaring exception, the assembly instructions are good.
tom
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(01-12-2021, 12:47 PM)anwalt Wrote: I offer a comment concerning the industrial mobile base.
first follow the direction about removing the saw from the box etc. . . . .
Place the immovable saw in your garage in your wife's parking place.
add the cast iron wings to the top, the fence rails . . . .
then get to the part where the saw stop assembly instruction says 'call your four strongest friends to help lift the (now heavy) saw onto the base'
totally out of the blue you need 4 gorillas while what is now a boat anchor sits in your wife's parking place
Not my idea of quality customer relations. A warning on page one that assistance will be needed would have been helpful before weight was added to the saw. I was 4 gorillas short when I placed the saw on the IMB. With this one glaring exception, the assembly instructions are good.
tom
The manual is lacking this advice too -
Place the immovable saw in your garage in your wife's parking place.
In case this isn't obvious enough - mount the cast iron wings AFTER the saw body is loaded onto the mobile base.
Simon
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