# Thien Baffle or Thien Tophat



## jgreiner

I see a lot of comparisons of the thien baffle or tophat vs cyclones and other separators and I've pretty much convinced myself that a thien baffle or tophat would be the way to go. I just cleaned out my dust collector again today god I hate doing that. Whoever designed the bag/ring system on the Jet DC1100 needs to be fired.

My big question really is what are the pros and cons of doing a thien tophat vs a thien baffle.

I have a router circle jig I plan to use to cut the circular portions of either the tophat or the baffle system, but other than that I will have to purchase all other materials used.

I plan on going with a 6'' inlet since that's what my DC1100 impeller is, and might as well stick with that, and close down to 4'' later down the line.

Which did you choose and why?

-jeremy


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## gfadvm

Jeremy, I chose a much simpler and easier to build separator which I really like. Look at my projects for the Shopnotes model I use.


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## jgreiner

I've seen that issue, but is it really that good? It just seems like it would cause a loss in CFM because of the way the air goes down .. then back up through the barrel like that.

-jeremy


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## gfadvm

Jeremy, I was very skeptical but I thought it won't cost anything and it's worth a try. I cannot perceive ANY decrease in airflow. I think I did a couple of things that helped: the floor underlayment made an airtight seal so no leaks, I tried to avoid 90 degree bends, and the plexiglass allows me to empty it before it gets too full. If I had it to do over I would use the whole 55 gal barrel and make my box to raise the dust collector taller. The divider in the box on top is only 8" deep as I remember so the air doesn't really deflect down that much. Try it, it's a quick and simple build and you won't lose much if you don't like it. I'm not familiar with your Jet. Is it about the same specs as my Grizz? I use magnets to hold my plastic bag in place until I can get that clamp positioned. This helps on the rare occasion I need to empty the plastic bag. I have had 4" of fine dust in the plastic bag since I posted it and it gets used daily and has produced many barrels of shavings/sawdust. I just saw that you have 6" outlets so your unit may be bigger than mine as I have 4". Keep me posted as to your solution.


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## jgreiner

Heya Gfadvm
I decided to try the shopnotes ones at very least a temporary solution, I went to lowes yesterday picked up the pipe fittings, some plexiglass and a cheap irwin blade to cut the plexiglass on. Got about halfway through building it when I almost killed myself using a HF circle cutter drill bit. http://www.harborfreight.com/carbide-tip-adjustable-circle-cutter-68117.html

I had my drill press down to 400RPM which is as low as it'll go (and way lower than my hand drills) .. and the freaking middle bar flew out of the drill bit while drilling the second hole. Fortunately it didn't hit me or anything but the wall, but it scared the hell out of me.

I'm gonna pick up a hole saw today to finish out the holes for the pipe fittings then I should be able to finish it today and give it a try.

-jeremy


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## crashn

I chose the top hat version. I'm about 80 percent done with the build of the top hat, about 70% done with the build of the new frame to hold the blower motor in the vertical position. I went with the 32 gallon trash can and I kinda figured that the top hat variation would allow me more room inside the trash can. I also liked it because if you use clear lexan, you get to see the parts go flying around !


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## ssnvet

same issue at my shop….

my plan is to put a combo thein plate / vortex cone *inside *my single stage DC.

this is the best I've seen on it so far

PW has an article about using a WOK as a cone as well, but I like Ary's combination of the two ideas


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## 47phord

I went with the top-hat variation based on comments I read on J. Phillip Thein's website. It doesn't cut into the can capacity and several people seemed to think it worked a little better, especially if you are using 6" pipe; I've never used a baffle so I can't comment on that. It is more time-consuming to build a top-hat however, and you have to be sure don't cut the slot too close to the edge of the separator (painful experience talkin' here); if I had to do it again I would probably go the baffle route and save myself some time.


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## b2rtch

I HAVE BEEN USING THE SEPARATOR FOR YEARS AND IT WORKS EXCELLENT


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## mark4345

Go with the tophat. I built baffle first, it worked great for most tools tablesaw, router table, drum sander….finer dust. Only issue was the need to empty the can more often as when it gets about half full the baffle doesnt work as well. Then i added a 12 inch jointer/planer, and the shavings from this since they are long and stringy are getting caught behind the pvc 90 that u need as an inlet for the baffle. This makes a huge clog and then it doesnt work at all. Everything basically goes into the filter and bag.

I am currently building a tophat design using a 55 gallon steel drum.









It was a sealed top drum, i cut the bottom off, cut a round hole for the d/c motor blower, and in the side of the drum cut an elongated shape to match a "coped" pvc pipe. The pipe is attached with epoxy and jb weld putty over the epoxy. the dropslot works exactly the same way as the baffle, without the pvc 90 to clog up the works. Also having the extra space between the baffle and the can collecting the dust this allows the can to be full before needing to empty it.

I am venting outside…which caused the need to the redesign. when the planer was hooked up i had a lot of mulch in the yard….


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## crank49

Jeremy, the devise Gfadvm built is called a drop-out-box in dust collector vocabulary.

There is absolutely no reason it would not work. It will have less pressure loss than a cyclone, thein or top-hat.
It will not catch the very fine dust a cyclone will, but will do a very fine job with the rest.

The price of catching the very fine particles is pressure loss. In fact, a cyclone can be designed that will capture smoke if you wanted to, but it would have a pressure drop of about 20" H2O, which is about twice as much pressure as most small collectors can even generate.

Even if I had a perfect collector I would probably still want a drop-out-box before the fan to keep big stuff from damaging the blades.


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## gfadvm

Jeremy, Glad to hear you survived that wreck! I was going to buy one of those a long time ago and remembered several people telling me how dangerous they were. I cut my holes with the band saw and just calked the entry kerf when I put it together. Let me know how you like it.


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## crashn

pictures of my before mentioned top hat and frame assembly. The blower is a PSI 3.5hp 220v blower with 2000cfm. Inlet is 7.75 reduced to 6". the top hat build was easier than I thought, i was real nervous, but my circle jig for the router worked good and i got good, consistent cuts.


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## dbhost

The baffle in the inlet ring has the distinct advantage of not taking up any more precious space in your shop than your current dust collector already does… There are no additional plumbing connections to make, so no additional flex hose, or smooth line bends to slow the airflow down… Likewise, and I can't make any claim to knowledge of the Jet setup, but on my Harbor Freight dust collector, the baffle build and install was plenty easy and fast.

The disadvantages are that larger bits and pieces have to get through your impeller before the can be separated out, and I discovered very quickly that oak knots hitting the impeller in an enclosed shop sound somewhat like a .22 caliber rifle being fired… It gets your attention quickly… The remaining issue is that your dust and debris still goes to your lower bag, and if it's like most dust collectors, they are a royal pain in the tail to empty…

Top Hat builds as well as pre separator builds basically revers the advantages / disadvantages of a baffle in the DC itself. The build is much more complex, takes more material, way more space etc… Extra ducting and bends to reduce DC efficiency…

I have not gone back to the baffle yet, but I am likely to, especially if it ends up with my shop getting moved out to a shed. I need to make sure I can cram everything in there!


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## fernandoindia

Hi Jeremy,

I planned to make the same as gfadvm. But before I gave a try just connecting the the in and out hoses to the lid of a plastic tank. It works great, and never ugraded the top baffle.


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## crank49

That's the drop out box I have been refering to. It's about 99% of all you need.


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