Size Questions

[TheNewSteveH]

I just found out about the Thien separator, and I have many dumb questions.

I live in Miami, so I don't have to worry about zero-degree air entering my shop when I pump air out. I would like to create a dust collection machine that lets me blow fine dust out into the yard, so it won't be in my garage with me. But to do that, I need a device to put between my tools and the air blower, to protect it from big pieces of crap. The Thien separator looks like a good option.

Here's what I want to know. How big does the separator have to be, and do I need a true dust collector motor? Is a 5 gallon bucket too small? Can I get away with a Ridgid shop vac? I'd like to save floor space and have something pretty portable. If I could use a Home Depot Bucket Head, it would be fantastic. I would rather not go bigger than a 30-gallon can.

I have a cabinet table saw, 19" band saw, Ridgid oscillating spindle sander, drill press, table-mounted router, and a jointer/planer. I also have a couple of handheld routers. I don't make a whole lot of dust. Takes me quite a while to fill a 9-gallon shop vac.

[phil (admin)]

For those tools you'll need a conventional DC-based unit.  Something based on the HF or Grizzly blower would be a typical choice.

[TheNewSteveH]

Okay, I can work that out. How big a container do I need?

Thanks for the reply.

[WayTooLate]

Container size has two factors:  Separator size and waste collector size. 

Smaller sized separators separate finer dust.  Larger collectors hold more waste. 

I have a number of machines in my shop (commercial woodworking) and we have a variety of solutions. 

Typically, I don't want to waste much time dumping sawdust, so I try to size the containers to handle 4 hours of continuous production.  Worst case, they have to stop and dump twice a day...

For sanders which generate only fines - we use separators made in 5 gallon paint buckets.  For planers and jointers which generate heavier chips, our separators are in 44 gallon Brute trash cans.    Many of these are attached to 10 & 25 hp bag-style dust collectors - which rarely get much material from the separators...

Some of our sanding machines run all day and generate a lot of dust.  These have a 5 gallon bucket mounted over a 55 gallon drum.  They separate the fines - but drop them into a big container that gets emptied every day. 

I also have some large chop saws which only make 3-4 cuts in an hour.  Those have vacuums which start quickly and suck enough for the large chip/small volume debris.

[Bulldog8]

Waytoolate, can you post a couple of pictures of the separators you have connected to your sanding machines? I am pretty happy with the separation I am getting off of my drum sander, but am always looking to improve. Do you have separate blowers for each of the baffles, or are they all piped to a large blower?

Steve

[TheNewSteveH]

Am I totally missing the point of the separator? I want something to capture the big chunks so I can blow the fine dust outside.

[TheNewSteveH]

I'm talking about blowing this stuff (fine dust only) either out onto my lawn or into a concealed utility area between the garage and house. The nearest neighboring house is around 150 feet away. On the lawn side, it's more like 250 feet, across a street, behind a thick wall of trees and shrubs. Are you saying that won't work? On a really busy day I produce about three gallons of sawdust, so it surprises me to hear that the fine dust, which is a smaller amount, would be a big deal.

I often use a leaf blower to blast excess fine dust out onto the driveway, and it hasn't been a problem, but it's not a very elegant solution. On blacktop, you can see the dust until the next rain or big wind, but I would think that on grass, it would be a different story.

Putting a bag outside won't work. It rains a lot here, and I can't build a shelter for it due to zoning issues. I could definitely get away with an exhaust duct, though. I don't mind catching and dumping the big particles.

I really don't want fine dust recirculating inside the garage, and it looks like the only way to guarantee that without exhausting the dust is to get a bulky sub-micron setup with tons of power.

As for the table saw, I have a Sharkguard on order. I want dust collection from the top.

I'm really sick of dust. If I want to use my tools, I have to do it all in one session, or else I have to shower and change clothes every time I turn a tool on. And masks are pretty awful. I don't think they even work (at least not the cheap ones). They don't seem to seal very well.

I've been told that dust collection is pretty much impossible for the band saw and jointer/planer, so maybe the best answer is to stick with a shop vac and continue blowing out the garage. I don't want to build a big project that only works with half of my tools.

[phil (admin)]

You can absolutely exhaust outside without filters.  Lots of people do this.  If you watch the video on youtube you'll see that barely any dust makes it past the separator.

[TheNewSteveH]

Ok, great. So if I get a 2 HP blower from Penn State or somewhere, I should be able to pull this off. Thanks again.

[WayTooLate]

Bulldog -
I am off for a few days, so I will try to remember to take some pics when I get back... 
Most of the separators are attached to our 10 and 25 hp units. 

We started with placing baffles inside the 'Brute' trash cans.  We just cut holes through their snap-on lids.  The baffle is set to the height of the 'step-in' at the handles.  Our baffles are made of 1/4" Baltic Birch plywood (because we use a lot of it and have it around).   

Those big cans work 'OK', but our 4" hose lines run ~450 cfm which is not enough to generate good cyclonic action.  It is acceptable for some of our cut-off saws which have mainly chips with little dust.  Our 5" lines pull almost 900 cfm and those work much better. 

For some of the sanders, we cut out the bottom of a 5 gal paint bucket, leaving about a 3/4 lip around the bottom.  We then cut a matching hole in another top of a 'Brute' trash can.  A little bit of sealant, some rivets with washers and we have a smaller, faster separator with big waste capacity... 

Our 'first generation' separators were quick and dirty to prove the concept and test their effectiveness.  While attaching the baffles to the trash can lids worked very quickly, they are awkward because you have to lift the entire baffle assembly up out of the can to be able to empty it.  We are in the process of creating replacement 'top hats' that only have to raised 1" to get the barrel out for dumping.  We will even test one that is 'hard-plumbed' to our dust collector - eliminating flex hose.  So we expect even better performance!


STEVE -
You are just going to get a lot better collection than you need to have.  It is not a bad thing - just more than you think you need... 
If you place a 'grate' in the bottom of your separator (perforated or expanded metal or similar), you can let the finer dust settle to the bottom and keep the 'chunks' above.  Then, you have some great mulch filler for your flower beds or planters... 

Enjoy!