I finally got around to testing and photgraphing my dust collector with the baffle mounted inside. I did not do any extensive tests, but I was amazed at how well it has worked so far. First off, I have a Jet DC 1200 with a cartridge filter from Wynn Environmental. They sell 2 kinds and they refer to them as the 35A series. One is spun bond, the other paper blend. The paper blend as alot more square footage of filter area and is cheaper, but probably does not last as long. Anyway, it always clogs up with shavings when I use my jointer or planer. I installed a flapper, but once it's clogged, it's clogged and if I forget to use the flapper, it can get so bad that I can't even move it. I also had installed a neutral vane.
To install the baffle, I first mounted the lower bag into the separator ring. The Jet has a very nice snap-in plastic ring that makes installation almost foolproof. With the bag installed, I rested the baffle against it, checked for level and attached it with 4 screws. The baffle is made of 3/4" MDF. The difference between the diamters is about 1.25". The 3 screws are #10 round head, about 1" long, the 4th one 2" long. I'm not sure the 4th screw along the small diameter section is really necessay, it was mainly to keep it level and I wasn't sure how much force would be on it from the air movement and I did't want any surprises. Once the baffle was mounted, I realized that I needed a new way to mount the canister.
The first photo below shows the canister mounted on the DC. I now use 4 rubber straps to hold the canister in place. These work much nicer than the hooks supplied by Wynn, even if you don't use the baffle.
The second photo shows the baffle inside the separator ring. The baffle is attached at 4 points. 3 along the large diameter section and a 4th to support the middle of the small diameter section. Note how the wood chips have caught on the 4th screw. The center hole in the separator ring is about 9" diamter. In the area marked "Dead Zone" there is no airflow when the DC is running. The air spills out of the hole at a very shallow angle everywhere except here. I had decided to remove the neutral vane, and believe that while it may increase airflow by reducing turbulence, it probably is deflecting unseparated air up into the donut hole, helping to clog the canister filter.
Also notice that the donut is tapered, sloping down towards the center. This is essentially an outlet pipe, but because the air exits the hole at a shallow angle, when a a cansister is mounted on it with a much larger diameter, the air must be jamming into a wedge like space between under the canister. This must be decreasing airflow. This did not occur to me until this morning, but what I need here is an outlet pipe extending UP from the hole to the bottom of the canister.
The 3rd photo shows the mounted baffle from the underside. This shows the configuration the best.
To test the effectiveness of the baffle, I did something that I thhought would normally clog the canister. Having previously milled alot of Ipe and then cleaned the pleats of the canister the best I could, the inside of the canister was clean and yellow in color. So I took a 1x6 pine board, 5 feet long and milled on the jointer from a thickness of 3/4" to only 3/16". It made alot of white shavings that should be very easy to see.
After milling the board, I carefully took off the canister expecting it to dump a bunch of sawdust on my shoes, but I was amazed that there was hardly a spec of pine sawdust in it! The 4th photo is shows the inside of the canister after the test.
The 5th photo shows the baffle from underneath, where the collection bag snaps in place.
The last photo show the separator ring from the inside, looking at the inlet.
For me the biggest unknown at this point is how full the lower bag can be before scrubbing occurs. At some point, the bag must get full enough for the dust to be blown out and up into the filter. I think that should be the next test, because once a canister is clogged, it is very hard to get it clean.
David
To install the baffle, I first mounted the lower bag into the separator ring. The Jet has a very nice snap-in plastic ring that makes installation almost foolproof. With the bag installed, I rested the baffle against it, checked for level and attached it with 4 screws. The baffle is made of 3/4" MDF. The difference between the diamters is about 1.25". The 3 screws are #10 round head, about 1" long, the 4th one 2" long. I'm not sure the 4th screw along the small diameter section is really necessay, it was mainly to keep it level and I wasn't sure how much force would be on it from the air movement and I did't want any surprises. Once the baffle was mounted, I realized that I needed a new way to mount the canister.
The first photo below shows the canister mounted on the DC. I now use 4 rubber straps to hold the canister in place. These work much nicer than the hooks supplied by Wynn, even if you don't use the baffle.
The second photo shows the baffle inside the separator ring. The baffle is attached at 4 points. 3 along the large diameter section and a 4th to support the middle of the small diameter section. Note how the wood chips have caught on the 4th screw. The center hole in the separator ring is about 9" diamter. In the area marked "Dead Zone" there is no airflow when the DC is running. The air spills out of the hole at a very shallow angle everywhere except here. I had decided to remove the neutral vane, and believe that while it may increase airflow by reducing turbulence, it probably is deflecting unseparated air up into the donut hole, helping to clog the canister filter.
Also notice that the donut is tapered, sloping down towards the center. This is essentially an outlet pipe, but because the air exits the hole at a shallow angle, when a a cansister is mounted on it with a much larger diameter, the air must be jamming into a wedge like space between under the canister. This must be decreasing airflow. This did not occur to me until this morning, but what I need here is an outlet pipe extending UP from the hole to the bottom of the canister.
The 3rd photo shows the mounted baffle from the underside. This shows the configuration the best.
To test the effectiveness of the baffle, I did something that I thhought would normally clog the canister. Having previously milled alot of Ipe and then cleaned the pleats of the canister the best I could, the inside of the canister was clean and yellow in color. So I took a 1x6 pine board, 5 feet long and milled on the jointer from a thickness of 3/4" to only 3/16". It made alot of white shavings that should be very easy to see.
After milling the board, I carefully took off the canister expecting it to dump a bunch of sawdust on my shoes, but I was amazed that there was hardly a spec of pine sawdust in it! The 4th photo is shows the inside of the canister after the test.
The 5th photo shows the baffle from underneath, where the collection bag snaps in place.
The last photo show the separator ring from the inside, looking at the inlet.
For me the biggest unknown at this point is how full the lower bag can be before scrubbing occurs. At some point, the bag must get full enough for the dust to be blown out and up into the filter. I think that should be the next test, because once a canister is clogged, it is very hard to get it clean.
David