Converting a HF DC to a top hat Thien baffle question

Got my Wynn filter today for my HF DC. I had put the DC together a few weeks ago, but never really paid much attention to it till I was installing the new filter. There's been some posts here with pics of the MDF "top hat" style Thien baffle. And, I figured on making one of these shortly. But I got wondering today, can't you just use the collector ring(?) from the HF DC instead of making the MDF setup? Sure, you'd have to make the slotted bottom base out of something (MDF), but you wouldn't have to make the outer ring. Now, on the HF collector ring, it's got a tapered, short, funnel built in to it. Would this be sufficient to use as is, or would you have to build a top with the piping through coming down below the funnel? Even if you had to build the top and bottom plates, this would still be easier (and faster) than building the ring itself. Greg

Greg, I'm a bit confused, I think you need/want to use your HF DC ring for mounting the filter and keep that on the "exhaust" side of your impeller, and you want the "top hat" Thien separator before the impeller. I'm in the home stretch of converting an old 2 HP Grizzly DC to a six inch Thien system. These two links have provided most of the design ideas I'm incorporating. The first is from a creeker; the second is from the Thien formum and provides great step by step instructions. He lines his top hat with formica. I was able to get the cheap, thin masonite to curve without snapping, but then wound up lining that with aluminum roof flashing. With any luck, I will have it sucking dust after getting back in the shop on Saturday. Good luck with your Thien.


http://www.sawmillcreek.org/showthre...ions&p=1607637

http://www.cgallery.com/smf/index.php?topic=429.0

I used the ring - I screwed a few blocks to the bottom side of my baffle shape, and then screwed through the ring into those blocks to hold the baffle where I wanted it. It was less time consuming to do it that way, and there are no support rods in the way to bother the air flow.
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In my case, I'm sucking through a bag (many suck through a barrel and then later dump the contents into a bag to discard... I just skip that step and remove the bag to discard directly) and then exhausting outside.. but you could just as easily do a very similar setup but exhaust through your filter.

Here's what it looked like before I mounted the motor:

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And here's what it looks like with motor mounted and exhaust through the wall:
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So that the bag will not collapse on itself when the motor is turned on, it's lined with a piece of rolled up fencing. It easily shimmies out of the bag when I'm ready to tie it off and throw it out. Then I just put the fence piece into my new bag. Works really easily.
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My favorite things about this setup are: to discard the dust, I do not have a dusty dump-from-barrel-into-bag step... and this setup takes 1/2 the footprint of a lot of the setups I've seen.

My least favorite things about this setup are: I built the entire setup from scrap I had laying around in about 1 hour, so mine isn't beautiful to look at like many that I've seen.


Also, here's a vid showing a test of the "suck through the bag" setup: http://www.youtube.com/watch?v=9MSOCePr35s

OK, here's the thing, I know a lot(most) of people like to put the Thien baffle in front of the DC, especially for the larger "chunks" that may be sucked up. But virtually everyone says that all they get in the collection bag is a "cup of sawdust every six months" or so. So what I was thinking (ouch!), if you use the collection ring in a Thien baffle configuration, isn't most of the dust going to go into the can below? And is a "cup" of dust left over really going to hurt your upper bag/filter that much?? And the one other thing I was thinking about, is the smaller size of the footprint of the whole DC. You'd save a lot of space this way. Now, on the other hand, looking at this from the other side. I haven't priced it out yet, but if you bought just the HF collection ring, would it work using it as the top hat center? Granted, a lot of people get a lot of satisfaction from building their own. But, if the price wasn't excessive, you have a ready made center portion of the top hat, rather than figuring, gluing, clamping, screwing everything together. Anyway, I was just wondering if any of this MIGHT work or if it was a pipe dream. Just thinking of some different ideas here. Greg

As I see it, the point of a separator, whether it is a cyclone or Thien, is to "spin" the dust out of the air before it hits your impeller and to reduce the amount of stuff that hits your filter. Over time dust will accumulate on the fins of the impeller. Big "chunks" of hardwood chips potentially will scratch and\or dent the fan blades. If you are going to suck all of this stuff through the fan cage, I don't know why you need a separator on the exhaust side. Stick your filter on the top of the DC ring, and the bag underneath. Building the Thien top hat will take several hours, no doubt about it, but it isn't that hard. If you don't want to go to the trouble to put it in front of the impeller, then I'd advise against doing it at all. Just use the Wynn filter on your DC in place of the bag.

I'm no expert, but from my reading on the topic: You can put the separator on intake or exhaust. My understanding is that in either case, your goal is to grab the vast majority of material (the "drop out" effect of the baffle, or cyclone) and collect it in a discard pile, so that only the smallest amount of debris hits the filter (thereby keeping it from losing efficiency so soon). In a case like mine, where I exhaust outside, the goal is instead to make it so that I'm not creating an absolute mess outside my shop. But any which way, the impeller on these DC's can handle the sawdust.

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Originally Posted by Joe A Faulkner

As I see it, the point of a separator, whether it is a cyclone or Thien, is to "spin" the dust out of the air before it hits your impeller and to reduce the amount of stuff that hits your filter. Over time dust will accumulate on the fins of the impeller. Big "chunks" of hardwood chips potentially will scratch and\or dent the fan blades. If you are going to suck all of this stuff through the fan cage, I don't know why you need a separator on the exhaust side. Stick your filter on the top of the DC ring, and the bag underneath. Building the Thien top hat will take several hours, no doubt about it, but it isn't that hard. If you don't want to go to the trouble to put it in front of the impeller, then I'd advise against doing it at all. Just use the Wynn filter on your DC in place of the bag.

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Nope, I'd disagree with this. What having a Thien filter after the blower gains you is it keeps 99+% of the chips & dust out of the filter. I've run a PSI "2 H.P." dust collector with Wynn filter without the Thien baffle then with, no other mods. The amount of dust & chips in the cartridge filter with with the Thien baffle is WAY less than it is without the baffle. I haven't had anything larger than planer chips going through my dust collector--well, maybe the occasional peanut shell--:D and even if I did the impeller is steel for a reason. I also don't generally use the D.C. to clean the floor so sucking up big chunks of wood or metal bits is not much of a concern to me.

I didn't go with the "suck through" design for two reasons. One is that I don't have the room for a bag and a container though some recent designs do away with the bag. The second is that according to Bill Pentz, "suck through" blowers are less efficient than "push through" blowers and you need a larger diameter wheel on a "pull through" cyclone than on a "push through" cyclone. The H.F., Delta, PSI single stage units aren't all that powerful to start with; I didn't want to do anything to reduce their efficiency. Different strokes for different folks.

Greg, I encourage you to visit the Thien forum and checkout this thread: http://www.cgallery.com/smf/index.php?topic=431.0. He has a 2 HP "suck through" setup, and reports great performance, and he has very long, 6" runs, with hard 90's in his set up. Curt, could you post a picture of your set up? I'm curious how the foot print of a push through configuration is that much smaller than a pull through.

Joe: I've been over on the site quite a bit, and I've seen that thread before. Looks like a nice setup. The thing is right now, I've just started to set things up. At this point about 1/2 the floorspace is being used for staining and finishing doors and woodwork to replace the interior doors in our house. When that's done, soon I hope, I need to build cabinets for 2 adjoining walls. And I don't know yet where everything will end up until I work out there for a while. At this point everything is on casters and movable for a while until I get a feel for functionality. I really don't want to permanently place the DC until then so I want it mobile too. That said, I'm leaning towards leaving it that way and moving it from machine to machine as needed. That's why I'm concerned about the footprint of the DC. I'd just like to keep it as small as possible for now. Might change it later, but who knows! I'll probably build the baffle "before" the blower, but I'm just curious about other ways of doing it. Greg

Greg, I am in the midst of remodeling my shop and completing the dc is my next highest priority. I plant on having the DC on a 22x45 inch platform configured similar to Howard's units (http://www.sawmillcreek.org/showthre...ions&p=1607637).

Initially, I am going to cluster my power tools similar to what this guy has done (http://www.finewoodworking.com/Works....aspx?id=23974), only I'm not building a single integrated island/workbench like Alan did. By going this route, I think I will keep the runs to a minimum. Once I get things set up, I'll update my shop remodel thread with some pics. I hope that Curt will post a picture of his unit, I'd like to see its footprint.

Hi Joe

Not much to post, really. It's a standard Penn State "2 H.P." dust collector sitting in a corner so the footprint is unchanged from the factory configuration. The only mod was to change the ramp in the funnel. The Penn State had a spiral ramp instead of the solid "doughnut" the H.F. Jet, Delta & the rest use and there wasn't room on the bottom of the funnel for the baffle. The idea I think was to impart more of a spin to the incoming material to get better separation. I don't know if it worked or not, my feeling is not. The Thien baffle sits in the bottom part of the metal funnel assembly. I didn't want a second top hat container because I'm space limited and couldn't figure out a good way to plumb it permanently. I know some people have disassembled D.C.s and mounted to blowers above "top hat" setups. Doing that you have to either exhaust the air outside or figure a way to duct the air into a filter setup. My D.C. plumbing runs close to the floor and I'm not about to change that anytime soon. My situation and preferences are mine, they may not fit someone else's situation or preferences. I don't think Phil's EULA restricts usage or configuration.:)

Hey Greg, Ive had lots of help here. I used the ring, but cut it to make it smaller so it would fit on top of a trash can. This also allowed me to use the inside baffle as a ramp as this part now became a little larger than the circumference, better if I show pictures.
No filter, motor over original ring then trash can underneath.Hope this may give you more ideas.
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