J. Phil Thien's Projects

The image is the drawing of the build I have been gathering materials and refining since I joined the forum. Although I am considerably attempted to jump directly to the in-line separator build I have commented on in Phil's post, I feel I need to stick with some semblance of order in my goal. So I am throwing this out for a look and possible comments. Perhaps it will inspire someone......or not  ???

So this would be a true spiral separator, along with a secondary section that is a traditional Thien top-hat separator but all-in-one.

Some build dimensions for perspective:

   
• minimum dust collection bin of 20", with a split down the center to divide the two separation sections This may be the hardest part since I would need to build it.
• overall width as it sits at widest point ~ 26"
• inlet diameter is 6", guided into a 10"h x ~3"t rectangular transition
• Outlet is 6" and would be a top hat style with the fan assembly on the outlet
• Appears eBay has sheets [48" x 96"] of rolled up HIPs plastic that should be stiff enough and slick enough but still very flexible to bend in one direction - it comes in a roll - to form the walls/spiral of the can - ~ $29.  HIPs can be bent and glued - so the running length of ~149" of can wall can be two layered - offset where one sheet meets the next to form a single smooth and very slick can wall.
• Plan to CNC the slots in the tops and bottom to hold the HIPs can sheet in place.
• Wood 1/2" top and bottom plate - top removable - not depicting the offsets/actual fasteners in the top and bottom - but flush outside not in airflow

Why? This is based on previous experiments I have completed including the offset increasing area exhaust tube - off set from the bottom. The goal being to flow only as much air as is coming in to avoid simply drawing all the airflow immediately to the outlet - dust included - and into the fan thus to the filter. The bottom outlet extension allows me to control the height of the suction and amount [due to the cutout height around the perimeter of the tube] and therefor WHEN it occurs. I found in a build that had a solid tube with such a cutout that as you only draw some air off "slowly" but "in increasing amounts about the can FINAL interior" that you tend to drop dust out to the bottom of the flow by gradually slowing the air speed/pressure front - allowing the fines to propagate outward and not have as much a tendency to simply get trapped fighting against the next incoming airflow. As they drop they are now positioned below the exhaust [the bottom outlet ring] and will continue to circulate due to speed and the next time they emerge into the incoming airflow they are positioned low and below the air outlet position and tend to be "held" in the low position by the incoming majority higher airflow that wished to move down in order to get tot he slot in the outlet tube - and air is stripped off the top/inner airflow. FYI - final height of the upper outlet tube will be less area than the inlet. Starved if flowing just air - but able to flow all air out of a mixed stream as the dust and chips settled out to the bin below.

There are issues. by using areas and not including frictional components plus other consideration I have had to experiment with the idea. Seems, as a simple solution but not exact, if you consider area for flow and then remember that you are NOT flowing just air. Again, If your flow is 1% dust, then you do not flow the same area if it leaves the stream. Therefore inlet and outlet are not the same, outlet is LESS if you consider the dust must drop out of the stream before exiting. So, using percentages of airflow I find around 5% dust capacity allows me to drop the outlet area dimension so as to draw more fine dust produced by my CNC and drum sander. Again, Perhaps the "adjustable feature" of the outlet area will enable me to fine tune for what equipment I use or just dial it in better. But, most likely I will leave it wherever the best fines collection occurs. If your flow contains dust you actually flow more than the reduced area of the outlet. It may seem strange, but the dust is riding the airflow, not part of it in this scenario and it appears to work, for me.

There is a lot more I could talk about, but I am not writing a thesis. Basically, wondering if anyone else has comments about their experiences with this builds parameters that I have found to be advantageous - just have not put them all into one build before this proposed [proposed because although I have been gathering materials, well, plans change]:

   
• taller narrower can and stream - ~10"h and 2.8"w
• longer spiral paths to exit - over 149" of outward centrifugal force experienced.
• note: inlet positioned at the top of can - allowing flow to expand DOWN towards the bottom to encourage dropping of fines/chips
• two independent chambers both sealed to allow separated balance of suction - no return from one section to the other. This was not spoke of earlier - but the two slots are separate and NOT connected - do not wish any vacuuming from one slot to the next. So hopefully the larger [and fines] particles will drop out BEFORE they leave the ring and airflow towards the4 outlet tube is encountered - thus allowing them to remain forced to the outer wall of the spiral and allowed to fall out in the first slot.
• calculated outlet size - limiting flow out based on experiment and areas/percentage of flow is air versus debris.
• increasing by expanding area outlet cutout - helps the air swirl stay established "around" the can rather than "heading to the exit" and limiting outlet. I know everyone sees their dust through a window traveling around the can but I have had success with this method. Most important is the raised outlet bottom piece - match areas inlet/outlet and you may see some benefit in your existing can. You can just add a bottom ring and see what happens and take it out if you don't like it.
• riser off the bottom of the can for the outlet to keep fines in the lower pressure airflow at the bottom of the can to encourage complete scavenging - they are "trapped and can not propagate to the outlet [under it]
• note there is no way to use a bellmouth in this build, unless you can place two opposing - but I have not seen much improvement although the bottom bellmounth [facing up] seems to keep debris along the bottom of the swirl I think it is counterproductive on the "coming down from the upper position air that MAY still have suspended fines and promote moving to/into the outlet.

The simple can may still be the best - in the long run - as per retired2's build. But then we would not be having as much fun either  8)
If I change my mind and go that way I think I would still use the raised bottom outlet towards the center of the can drawing off the air from the stream limited to area calculations, with a taller can and narrower transitioned inlet.

That's it. Will advise as/if/when I finish. Also will be looking to do a better job of writing down measurements rather than just observations - will require the installation of several manometers/vacuum gauges to report. I intend to do that no matter what I build next. But I have been intrigued by this since  my initial drawing several months ago. I have been experimenting with the parameters since then. Now I am on iteration #24 and finally satisfied with it and the ability to build it fairly cheap.

A few photos, it is very hard to actually understand - for me - the difference between the stock HF fan inlet and the 6" inlet/spears long 90 degree from my earlier posts so I thought these may be interesting to some of you:

    "my best harbor freight mods, thoughts, intro."
    "6" LONG SWEEP PVC 90 degree elbowDWV [not tight bend] on Amazon - $14.60"

So here are a few images for both so you can see the difference and the reality of seeing them may actually be stunning. I bought two of the 6" to 4" so the one here is new, along with the 6" spears 90, while the HF original is still dusty and dirty off the shelf. You can see the stock HF gets lost in the 6" spears, and again, the new impeller per post makes a big difference. The pipe in the photo is a 6" hard cardboard tube for a new build to test a few thoughts - I find sonotube [concrete tube form] or packaging tube works fine for low cost testing.

They say a picture is worth a thousand words  ::)

Found this on Amazon, just purchased, thought others may be interested. Be aware, most 6" PVC is not 6"ID, usually slightly less.

I intend to use this in a test of the inline separator per my comments on Phil's thread - "An inline separator idea".

Others may wish to use it for other reasons. It is the cheapest I have found so thought I'd throw it out since a lot of others use "6 inch" PVC for other items such as runs.

I do not represent/work or am in any other way associated or have any vested interest in this item other than stated.

http://www.amazon.com/gp/product/B009H4N4DU?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00

Spears P309 Series PVC DWV Pipe Fitting, 1/4 Bend, Long Sweep Elbow, 6" Hub x 6" Spigot

As a first post I am throwing this out for whatever comes back. If I make a mistake, correct me, it has happened before. If I repeat others, sorry, these are my opinions - some calculations, some training.

My HF-DC modifications I consider as best before/after a Thien baffle. The HF-DC is basically the same as MANY other higher rated DCs. They are all made in China and not everyone makes their own unit. I am NOT including all my internals or other changes/Thien permutations as everyone has different ideas on that subject. I do believe the modifications I am presenting will provide noticeable/measurable improvements out of the box no matter if you Thien, other or not. Perhaps they have been covered, if so, sorry. Still this is my experience and if nothing else a reassurance that someone else has indeed done them.

FIRST, the best health benefit is from using a Wynn Environmental Cartridge Filter. No matter what you do, how many stages, can, cyclone or other - the filter is the LIFE SAVER. No one knows how many failed modifications I have tried in the pursuit of better separation - and the filter saved my %#$@ and prevented days of cleanup inside my home. My filter: C1425C  Nanofiber, MERV 15   99.999% @ 0.5 Microns, Single Mounting Flange with pre-drilled holes, 18.75" OD, 14" ID x 25".

Second best modification, I ordered a Rikon impeller for my HF DC. That took me to new flow heights -  impeller size from a 9.75" diameter to a true 12" diameter. Rikon - 877-884-5167 - ask for parts, do NOT talk about your HF-DC, state you need an impeller for a 60-200 DC, part #22 for the impeller. Part #26 for a new bolt and part #27 for the "spring washer". You can use the old bolt and washer - I did - but bought the new ones anyway [why you ask - because I am that...]. Total cost for all of it - $120.27 including S&H. Download the Rikon Manual for a 60-200M3R.PDF and check for yourself - suggest you always do so. No issues with the HP everyone talks about with a bigger impeller - it just works. Helps all those SP and other frictional issues big time.

Third, the inlet to impeller is 5" - actually slightly smaller. Open it up to a to a 6". Amazon sells - Big Horn 11603 6-Inch By 4-Inch By 4-Inch Y-Adapter - for $13.99 allowing more air in. I cut a wood ring, epoxied it to my intake plate to mount it to. I epoxied it first, using the old hole to center it as the new ring and then cut/ground/sanded the sheet metal plate holding it to the inner diameter of the 6".

Calculations based solely on close [NOT exact] physical dimensions -  not considering frictional or other components:  HF ~5" intake area 19.6sqin {less actually - it is NOT 5"}, ONE  4" intake area of 12.57sqin, TWO 4" intakes an area of 25.13sqin, ONE 6" an area of 28.27sqin - so flow two 4" to the 6" whereas I can not with the SUB 5" intake.

If you change the fan housing exit from the hose to the rectangular housing exit, by remounting the stock blower [lots of you] and make it in-line with your new Thien can - rectangular exit 6" x 5" - area 30sqin. Those area numbers are beginning to line up.

Simply matching and straightening ports in-line/areas in a NEW can - helps to offset any pressure and flow loses you may get from adding better separation. That impeller will really help too.

We all realize, the HF can along with most others has a lot of flaws you can not overcome if you want better than a little. Can height and inlet positioning/angle/flow - the dish, once you add to it, well, flow is limited and scavenging is compromised simply by the Physics of it. You are confined to a number by the can, which is one reason the larger, rebuilt Thien cans really shine. If you are two staging with the stock can, then you are still compromised and limited. This goes for a lot of other same style DCs.
Flow "straighteners" discussed many times by retired2 and he is correct. Any flow stabilizer will help. Yes, in-line to the impeller and in-line within the fan outlet/inlet to the "can" should be tweaked with vanes that allow the particulate dust in the column to migrate outward with the centrifugal force imparted by the curve and not allowed to create air boundary layers. The fine lightweight particulate can be suspended in a moving air column and at times will not penetrate the individual velocity boundary layers created by other means.

Bellmouths - CHEAP - as "speaker port tubes" - "Pair of 6" ABS Speaker Ports" on eBay for $18.95 with free shipping, Parts Express and Amazon have them too. A flat horizontal ring extension at the end of the tube - if no bellmouth - would be the second best option.

Suggested health reading for new site visitors -  www.cdc.gov/niosh/pel88/wooddust.html
  Also interesting:  www.osha.gov/SLTC/etools/woodworking/production_wooddust.html

On OSHA's site "Sanders, shapers, and routers generally produce the greatest amount of dust. Conventional means for exhausting these machines are not very effective. NIOSH has developed new, innovative means for controlling dust exposure from these machines, but these methods are not yet commercially available" - cute. Most of us see with our our eyes and experience that high speed belt sanders/slow FPM router cutting will create very fine dust. I save some of the fines and use it as wood flour in some of my epoxy glue ups. Most acknowledge that saws will create coarser dust and planers the coarsest - generally.

I am a consulting engineer with some experience in related fields, not directly related to any hobby dust collection or other such scale OEM. I do not think I am the expert, never will. Forgive me if at times I sound like the authority when giving what I know - how else can I do it? Again, I am attempting to contribute just like everyone else. Many can think outside the box, the Thien baffle is a perfect example. Is a properly constructed/sized cyclone better - in my opinion the answer is yes. But I want something at home and running ten horse(+) with a ten foot (+) stack or a baghouse/electrostatic/shedding filter media/back pulse/shaker setup won't cut it at home.

Oh, sometimes running your outer bag inside another chamber will help if you have the room. Using it as a 5u pre-filter that is easy/easier to clean before the Wynn can really be beneficial. It will cake and if you can place a viewport in the chamber, you will know when. Using a home built simple "pressure meter" may help you check flows at various points in your setup. You can make one or use those CHEAP pressure meters on eBay or your favorite store. You may not get the right reading - but what we are looking for is CHANGE in reading from a CLEAN running system to one that over time is loading. You will develop knowledge of your setup and have a better idea of something that is wrong or time to clean. Obviously pressure gauge for blow, vacuum for suck applications or buy a dual meter.

I looked for and found a link to some info that you can check for pipes and flow - see what your added frictional/area straighteners/pipe runs are doing here too:  http://www.omega.com/green/pdf/AIRFLOW_MEAS_REF.pdf

So thanks to everyone, very interesting reading and maybe if it just works - like retired2's - then maybe that's the ticket. Sometimes too much - perhaps some of what I speak of - is just that, on a declining returns curve. Maybe some is insignificant in the scheme of things. But I am interested and hope to contribute for what it is worth to anyone. For me, it is about HEALTH.

Thanks Phil, and thanks for allowing me to join.