Confused

[Dougp28704]

I am new to the forum. I wish I had researched more before I purchased my Dust Collector.
I bought:
Harbor Freight (Central Machinery)
CFM: 1550
Horse Power: 2


I really like everything I have read and seen on the Thien Separator. Brilliant. Now I have info overload after all I have read (so many hours over the last week). I planned to use my DC with Separator. And Rockler's 4" Dust Right expandable hose to stretch from one machine to another. The hose stretches 4x the relaxed length. I bought the 3 foot hose and planned to go from machine to machine with it. Would I be better off building the Separator for a Shop Vac and caulk up the purchase of the DC as a learning experience?

[sailfl]

Doug,

I have a original baffle design in my HF collector and it has been working fine.  The new Top Hat design is better and it can be used with your HF.

I would not use the expandable 4" hose from Rockler.  I have that hose for cleaning up around the shop but I would buy regular hose for my system.  I also think you might want to consider using 6" hose for the additional suction.  I am converting to 6" piping that you buy at HD or Lowes for AC.  I have seen a system that uses 6" with a dust collector like the HF.

[Bulldog8]

You didn't say what machines you wanted to collect dust from, but if you want to collect from a tablesaw, bandsaw, jointer, planer and other large tools the true DC and baffle is the way to go. Choosing a tophat or a internal baffle would be a choice based upon your preference, space requirements/limitations and whether or not you want to mess with emptying the bag.

On the other hand if you are only collecting dust from hand held tools like sanders, routers and the like, I would choose a shopvac and a 5 gallon separator.

The high CFM of a DC provides the amount of air movement to correctly collect dust from the large chambers of the tablesaw, planer and other large tools. A Shop Vac has a high static pressure (how hard it sucks) but a lower CFM in comparison. The Shop Vac does a great job of collecting from small tools or areas. I use both in my shop and couldn't really imagine one replacing the other.

Steve

[galerdude]

You didn't say what machines you wanted to collect dust from, but if you want to collect from a tablesaw, bandsaw, jointer, planer and other large tools the true DC and baffle is the way to go. Choosing a tophat or a internal baffle would be a choice based upon your preference, space requirements/limitations and whether or not you want to mess with emptying the bag.

On the other hand if you are only collecting dust from hand held tools like sanders, routers and the like, I would choose a shopvac and a 5 gallon separator.

The high CFM of a DC provides the amount of air movement to correctly collect dust from the large chambers of the tablesaw, planer and other large tools. A Shop Vac has a high static pressure (how hard it sucks) but a lower CFM in comparison. The Shop Vac does a great job of collecting from small tools or areas. I use both in my shop and couldn't really imagine one replacing the other.

Steve

+1

Additionally, I have a HF DC system with a Thien TopHat and 4" piping. I also use it on one operating machine at a time.

• Does it operate satisfactorily and meet my needs? -Yes
  
• Could I improve it's performance with further improvements? -Yes, I'm sure I could.
• Is the Thien separator  the best part of my DC system? -I think so IMO.

The point being, I think you could proceed with your initial plan and be very impressed. If your budget and time schedule allow, make all the improvements you can.

Best,
Gale

[Peter]

So.

I'm not so new to the forum, but I am new to setting up a dust collection system. I read (and try to comprehend) everything in the several wood working forums I belong to on the subject.

And I am still confused.

Not about the value of installing a system--there are many and varied and often contentious threads on that subject. That dust collection is necessary (or "a very good thing to have") isn't in dispute. I believe that ANY dust collection system is better than no dust collection system. And I think galerdude is spot on saying that improving whatever system is employed in a shop is an ongoing endeavor.

No, my confusion is on what components I should incorporate in my own (and no doubt unique--or nearly so) system.

Based on more comments that the HF "2 HP" unit is a "very good value" and that I "won't be disappointed in the investment" I bought one. Out of the box, it's . . . meh. I mean, it sucks up "some" dust and chips and deposits most of it in the poly bag. But the filter bag is just pure garbage. There is no question that better filtration is required. It's obvious that modifications to the HF unit are required to improve dust collection.

I am 100% convinced that Phil's separator design is the cat's meow. I built one for use with a Shop Vac and am thoroughly impressed by how well the thing works. I will definitely install a similar device in my central DC system.

So maybe that's half the confusion cleared up.

The investment in a Thien separator and the HF unit is <$200. The budget director is pleased. But I haven't told her yet what the bill for the piping and gates and fittings and all is going to amount to. Way more than two hundred bucks!

Like most everyone, ultimately, I waded through Bill Penz's dissertations on dust collection, looked at what all the other pundits and number crunchers have to say on the topic. I became thoroughly frightened that my $200 investment was a "bad idea" and I should have hocked the Volvo and my pickup truck to buy a more powerful system. But if I admitted that, my standing with the budget director would be on very narrow footing. (She really likes the Volvo.)

One pundit says, to effect: "You can't move enough fines through anything smaller than a 6" diameter pipe." Another says, to effect: "It is impossible to move the output from your table saw or jointer planer with less than 400 CFM and that's not possible in 4" pipe." And: "don't use elbows, they destroy system performance." And so on. I know you've all read the same stuff.

So, having designed the DC layout for my shop using 4" pipe, I redid it using 6" pipe. I also bought a length of 2729 S&D and fabricated 90? and 45? sweeps. (Translation: fun with a bandsaw and several packages of JB Weld.)

Then I visited the Woodcraft store that isn't near to me, but is closer than any other, and looked at their classroom shop. It's approximately the same size as mine, has approximately the same compliment of machines, and it's plumbed all in 4" S&D, with those ubiquitous cast aluminum gates and there must be as many if not more fittings than I plan, and half again as many feet of run. I asked the guy there at Woodcraft how well the system works.

He said, "It works very well."
"It picks up all the dust?" I asked.
"Yep," he said. "Why?"

It was then that I laid on him my load of confusion (basically what you read above), and he just shrugged and repeated that their system works fine. Apparently, they use a 3 HP cyclone. I didn't see it, nor do I have any information as to the FPMs or CFMs, which I believe are more pertinent than the power of the motor driving the system. I also don't have any data on how many gates might be open at once in that classroom. I plan on using my HF thing with a Thien separator in front, and (when the budget director approves, a cartridge filter, such as supplied by Wynn). And as I work alone, there is no reason to have more than one gate open on my system at a time.

So now here I am, looking at these gorgeous 6" sweeps (well they're not gorgeous, really, but the are pretty cool), and am wondering if I'm obsessing about the thing too much. What if I did revert to the 4" layout (using similar sweeps in lieu of elbows)? It would certainly please the budget director.

The thing that gets me is this: If I invest in 6" pipe, what happens at the machine? The ports (or the logistics of space for anything larger) are all 4" or smaller. So isn't that the weak link? The inlet on the impeller of the HF is 5". I love physics but I'm not very good at it, yet I seem to recall that in a fluid system such as an air duct, as volume increases, velocity decreases.

If dust-laden air is sucked into a 4" pipe that fairly quickly grows to 6", things slow down. No? At some point, the little Chinese motor and 12" impeller at the HF unit are just not gonna be able to keep up. No? (Then I read that inserting a separator of any kind impairs the system even further. Yet I will have one of those!)

Here's my proposed layout:

[Dougp28704]

Thanks for the input everyone. I was so discouraged before the replies. Bulldog, I plan to use DC for Table saw, Jointer, and Planner. Band saw if/when I get one. One machine at a time.

So, everyone pretty much feels the top hat is better than what I call the original with the elbow at the in-let? I have seen many pictures of the new design, but not enough to figure out how to make one. I'm not looking for dimensions, just how it goes together. I know there are many variations. I'm just trying to find simple sketch or something.

I have dreamed about setting up a shop since I was in High School wood shop. Now I'm 43. Over the years I have been buying tools. Have not really made anything yet.

Thank you

[Peter]

I never built an "original" Thien "elbow-type" separator...instead, I went right to the top-hat concept. So I can't comment as to the effectiveness of the elbow design--obviously it works or Phil wouldn't have shared it with us.

But I can say that the top-hat concept is close to 100% effective. At least with a shopvac. I'm still confused about the issue of pipe size, and all the other stuff.


ETA: Doug, do you have Sketchup? I'm glad to share my sketchup drawing for my tophat design.

[galerdude]

Thanks for the input everyone. I was so discouraged before the replies. Bulldog, I plan to use DC for Table saw, Jointer, and Planner. Band saw if/when I get one. One machine at a time.

So, everyone pretty much feels the top hat is better than what I call the original with the elbow at the in-let? I have seen many pictures of the new design, but not enough to figure out how to make one. I'm not looking for dimensions, just how it goes together. I know there are many variations. I'm just trying to find simple sketch or something.

I have dreamed about setting up a shop since I was in High School wood shop. Now I'm 43. Over the years I have been buying tools. Have not really made anything yet.

Thank you

Here are links to the two "how to" builds that finally got me building one.

http://www.jpthien.com/smf/index.php?topic=429.0
http://www.jpthien.com/smf/index.php?topic=431.0

There are other good threads too. These two just happen to be the ones that made it happen for me. Good reading!

Best,
Gale

[Dougp28704]

galerdude, thanks for the links.

Peter, I dont have Sketchup. I do have SolidWorks. Can you export as Dwg, DXF, IGES, or any cad format? if not, a jpeg would be fine too. Thanks.

[Dougp28704]

Peter,

The dxf design you send me came in fine into SolidWorks. I could build it directly from your design. All of my questions were answered. Thanks again.

I havent started making it yet, and I am already over thinking. If I mount my DC impeller in-line above my seperator, the direction is counter-clockwise when looking down from above. The same as in the jpeg you posted of you shop lay-out. Would you sugest that I mirror the design of the seperator? In order to have seperator rotaion the same as DC rotation?

[RonS]

I don't think you can go wrong with the orginal Thien Baffel "elbow" or the top hat design. I've been using the original elbow baffel with a central shopvac set up for many years and it works like a charm. I have 6 2.5" pipe drops run to all my machines and work areas. I am upgrading to a Delta 50-760 DC with a thien tophat seperator and 5" metal pipe replacing my 2.5 in pipe. I'am using 5" pipe because that is the size of the intake on the 50-760. I will run 5" pipe right to the machine outputs and use 5" to 4" reducers at the machine until I can figure out how to improve the machine ports. I'll continue to use my Thien shopvac for shop cleanup and small handheld tools.

From my experiance with the orginal Thien baffel I would not consider running a DC without a Thien Baffel based Seperator of some Kind. You will run into filter clogging issues if you do a lot of fine sanding but this is a problem with all DC systems.

I've attached a PDF file that shows the parts and deminsions I used to build a tophat seperator. The deminsion you should start with for a tophat is the inside diameter of your collection can, that would be the OD of your thien baffel dropslot. The inside height of the tophat can be the diameter of your input pipe. I used 5 15/16 because that was the width of the inner ring materal I had. I think a round to rectangular input transition is also a good thing because it reduces turbulance at the tophat input. At final assembly I will double back tape all the layers together to seal up any leaks.

I created these part drawings using DoubleCAD XT.

[Dougp28704]

RonS,

Thanks.

I may stil be confussed about somethings. But I now understand how it all goes together. This is a great site with helpful people.

[Peter]

Peter,

The dxf design you send me came in fine into SolidWorks. I could build it directly from your design. All of my questions were answered. Thanks again.

I'm glad it's of some use to you. :)

I havent started making it yet, and I am already over thinking. If I mount my DC impeller in-line above my seperator, the direction is counter-clockwise when looking down from above. The same as in the jpeg you posted of you shop lay-out. Would you sugest that I mirror the design of the seperator? In order to have seperator rotaion the same as DC rotation?

Yeah, I noticed that, too. I believe, based on comments hereabouts by retired2, that rotation of ANY air moving into the impeller is detrimental. (shrug) I arranged my set-up as you see because of physical constraints of the machine room and it's relationship to the workshop. I think I will try some sort of "air straightener" as implemented and tested by retired2. Thinking maybe a stack of aluminum "egg crate" diffuser in the inlet pipe just might do the trick...we'll see.

More important to me is whether to install 6" pipe or 4" pipe. I will use S&D PVC (ASTM D-2729) for two reasons: I can work PVC with significantly more success than metal, and it costs a lot less. 4" pipe and especially the associated fittings, is considerably cheaper than 6", but dust collection pundits claim it won't "do the job".

I am still confused over this issue, and no one's saying yea or nay to either, at least with enough supporting data for my satisfaction. Supposedly, you don't get enough "fines" removal in 4". The HF impeller unit has a 5" inlet. They don't make 5" PVC. I'm worried that necking up from 4" to 6" then back to 5" will result in a "less than optimum" situation. So although I spent two afternoons making 6" PVC sweeps (yeah, they're neat looking), I am leaning toward a 4" system. I can't see a scenario where I would intentionally use more than one drop at a time, unless I forget and leave one open.

And then I read that RonS is happy with his 2 1/2" system! sheesh. Will anyone weigh in on this issue?

[sneezy]

Peter, could you give some detail on how you made your sweeps?

[sneezy]

Woops-don't know how to insert quotes!