Confused about Dust Collection

David: "...HorizontalMike, how well does your trashcan separator work? Which one did you use? Grizzly has one that they charge $35 for. Sounds like an intelligent system buildup…."

I have BOTH the DIY Thien and the Grizzly separator. I dedicated the Grizzly separator w/can to my miter saw with a 16gal shopvac. Works great, especially with a hepa filter. The DIY feeds the TS, BS Jointer, Router table extension with a rotating 10ft section of 4in flex tube. And a 20ft flex tube to the planer. All fed one at a time by rotating the hose to machine in use.

IMO, both work equally well, though when the Grizzly plastic separator is full it will dump more rapidly into the main collection bag, where as the DIY Thien separator continues to keep most of the chips separated and you just start to see the overflow start with much less fortitude and speed. In other words, with the DIY you can determine when to empty the can more quickly.

This usually means that you can empty the can ONLY, without always having to empty the DC bag as well. While that may be a minor point, it does save time and you do not have to empty the DC bag as often, maybe every 3-5th time, whatever you are comfortable with.

david, you could get by with just a shop vac- the dust collectors are best when you plane/ joint alot of lumber..

i have a small shop vac, dedicated on:

router table
band saw
mitre saw
sanders

my grizzly DC with canister on:

Table Saw
Jointer
Planer

I have little to no chips on any of my bigger machines, and the shop vacs turn by switch on the machines theyre hooked to…

I would also get a air filtration unit…. thats thing keep my shop free of dust….

Bert, the standard hobbyist dust collector has been with a bag, maybe a cartridge, but without the automatic filter cleaning process your production shop uses. The cyclones are the only systems in the hobbyist dust collection product space that have a mechanism for filter maintenance.

Burt, what dust collector do you use in conjunction with your air filter? Do you have a cartridge? A nanofilter? A cyclone? Did you consider just putting a fan in front of a fine capture household filter like the high end 3M model, may in conjunction with their carbon filter for VOCs?





Michael (crank49), if we used an ESP after a cyclone it should capture fine particles without a fire hazard. In commercial systems, it seems baghouse solutions dominate woodworking and finer particle capture isn't an issue. But those systems are located outside. For a home system that exhausts inside that fine particle capture could be useful.

The are lots of ESPs that are sold for residential use. Like may woodshop dust collectors, failure to perform frequent and adequate cleanings renders them ineffective. However, one could be used to create an ESP for home woodshop use.

Do we have a solution for VOCs in a home woodworking shop?

My wife is sensitive to anything I paint. I have an HVLP sprayer I bought over 12 years ago. However, the drying paint emits VOCs. I think there are some paints that are lower VOC. My wife's nose is very sensitive, I lost my sense of smell about 7 years ago.

You can solve your dust capture issue, the questions are cost and local zoning. Ideally, put a significant cyclone-the Penn State Tempest S, the Grizzly G0440/G0441, Oneida V-Series or Super Gorilla, ClearVue Cyclone-outside in its own shed. For each tool ensure both the tool and hood are sufficient to capture the dust generated. Then back it up MERV 15+ filter running through a fan in the shop.

Once you put the dust collector back in the shop (The Donaldson Torit site has no commercial dust collectors in the shop) you need to have a filter capable of MERV15+, a cyclone strong enough to pull nearly everything, and motor/impeller powerful enough to drive it. This is modified HF vs. ClearVue decision is not unlike the Grizzly 1023RL vs SawStop 3hp PCS decision: both work, one provides greater safety at much higher cost.

The race car in the picture is an example. It had a bunch of safety stuff not common when it was added: collapsible steering column, extra 10lb extinguisher with thermal switch next to the fuel cell, a pressure switch set to cut the engine electrics when brake line pressure exceeded a threshold (set to 900lb, 600-650 was normal max range), the driver suit was a PBI with a very high TPP and protective underwear and baliclava were always worn (which is very hot in a stock car on a summer evening), I was using a HANS device when they were still difficult to get.

A few of those were prompted after a 2001 T-bone accident. In woodworking, unless there are fingers on the floor, the cause and effect aren't as clear.



Everything has a cost performance tradeoff. Short of spending $2500 for dust collection, it seems we are finding what the best middle ground is. For some people cost is the dominate factor. For other performance. Most of us are some place in between.

For me, the low end is probably the Grizzly 703P or PSI Tempest. I would add a cyclone and canister to the HF, raising the price to over $540. The 703P at $840 and the Tempest for $120 more offer advantages and simplicity worth the difference. Both solutions are one machine at a time with a short hose. For the table saw, that would include a flexible hose at least 12' long.

Any of the Oneidas and ClearVue would be over $1500…and approaching $2000. The Grizzly 2hp and the PSI Tempest S would both be about $1200-1300 when the dust settled (pun intended). Either should be able to handle one large machine over an arbitrary fixed ductwork of 20-50 feet. Neither specs their filters with a MERV rating and it currently isn't a nano filter.

Oneida specs their filters as MERV 15 or MERV 16, some as HEPA. ClearVue specs their standard filter as MERV 10 and has a $100 upgrade to MERV 15: Filter Efficiency: 99.99% at .5 micron (MERV 10)
Filter Upgrade: NANO - 99.999% at .5 micron (MERV 15). Presumably the PSI and Grizzly filters are MERV10 range. Those are all particle size capture numbers. They require some mechanism (e.g. a good cyclone) to keep the filter clean. And they do nothing for VOCs.

A list of the MERV standards: http://www.oneida-air.com/PDF/merv.pdf

Has anyone used the Oneida Super Dust Deputy and retrofit HEPA filter am HF or inexpensive Grizzly?

While I still may not have the right answer, the threads have been very helpful in clarifying the issue.

First, the objective. There are 2 parts. The 1st is to collect wood chips and visible sawdust to keep the shop clean and to not be wearing it at the woodworking. The 2nd is to collect fine dust from wood and wood products (such as MDF) that can be to size of bacteria or virus. That is critical to maintaining your health.

Second, commercial wood shops are significantly different than most home and some small commercial shops. These shops have their extraction systems outdoors with the makeup air provision that is significant in size. It appears that a filter system (called a baghouse system) is overwhelmingly preferred system for these commercial operations. They differ from the typical home dust collectors that use filters and having an automated system to continuously clean the filter.

Third, the only way to filter the fine particles is with a filter. The industry specifications for fine filtration are usually MERV or HEPA. For fine filtration the MERV filtration would have to be 15 or greater. The HEPA filters would be 16 or greater.

Fourth, the objective of using the cyclone is to protect the filter when no other mechanism is available to keep it clean. An effective cyclone will trap virtually all visible and most invisible particles. As long as it meets this objective the nuances of one design against the other are not important. It is like bench racing at a bar over which car is quicker; it only matters on the racetrack and then what might seem fastest on the spec sheet may not be best. And even then, the differences may be insignificant.

Fifth, and a home shop where only one tool will be used at a time the system needs to provide the needed airflow tool given the restrictions of getting her into and its dust hood and the ductwork leading from the tool to dust collector. I'm not clear on why having too much airflow will do. My guess is it will increase the vacuum in the ductwork and tool and possibly suck the sawdust out of the cyclone in its collection bin.

Sixth, the combination of a motor and impeller need to create the correct airflow through the system for the fifth objective. If they don't create enough, the system won't function adequately. If they create too much, the system may also not function as previously discussed.

Seventh, most of us have no tools to effectively measure air quality, in this case specifically particulates suspended in the air. Another discussion, air quality may also include CO2 and VOCs. So for nearly all of us we are just guessing.

So the starting point has to be to filter. Do not adversely impact the woodworkers health, that filter should be a MERV 15 or greater or HEPA filter. The larger the filter the less airflow restrictions it will create an no longer it will last between cleanings.

The cyclone needs to be effective for the volume of airflow and size of particles being captured. The cyclone actually doesn't care about volume, it cares about the velocity. I told the correct velocity is in the 3500 - 4000 feet/minute range. The equations the efficiency of the cyclone are function of the density and size of the particles, the density and viscosity of the suspending medium (in this case air with minimal compression), and the dimensions of the cyclone.

It would appear most of the cyclones are an acceptable range. Some are a little better than others and some undoubtedly have a lower pressure drop than others but we have no measurements to determine that. The relative pressure drop in the cyclone would only really be an issue if we were purchasing the cyclone independently of the motor/impeller. Except for some home built systems we aren't; instead were buying complete systems.

The smaller cyclonic systems - the 2hp/13.5in Grizzly 703P, the Penn State 2hp/12" Tempest, the Oneida 2 hp V-System - appear to be designed to be moved near the tool being used and connected directly with a short flexible duct. In that case they appear to be able to develop sufficient airflow and velocity to operate. Note that not all of these models come with a MERV 15 or HEPA filter.

The next step up appears able to handle a single (and in some cases two) tools in a modicum of ductwork connecting to the them. While I don't have definitive numbers, scrounging through the various ductwork design guides I'm guessing the back pressure through the tool to the dust collector probably 5 to 7 in/H20. To get the desired cyclone inlet velocity with a 6 inch duct that would be 650 - 800 CFM and with a 5 inch duct it would be 475 - 550 CFM. Both numbers are in the range of what the duct design guides specify for a tablesaw.

As long as they have appropriate filter and are collecting all of the dust any of the systems - whether a modified harbor freight, a home built wood cyclone, a ClearVue, or Oneida Pro-series - would be adequate.

When buying a complete system cost is an issue. I am waiting to hear back from Grizzly about the availability of their systems with nanofilters. The Oneida and ClearVue systems are nice, but also among the most expensive. In my shop, I won't be able to easily wheel around the dust collector, so the smallest systems are probably not viable. That would leave the 2hp/14" Penn State 1425 Tempest S, probably with a muffler. If the airflow is too great, I could create an additional inlet port with an automotive air filter for noise attenuation and a blast gate for volume control. If the Grizzly did come with the nanofilter, the 2hp/12.5" G0443 may be the most cost effective solution.

I'm begening to wonder just how confused the OP really was/is. A lot of good suggestions have been made but in every instance it seems there is a response from the OP trying to indicate he knows more about the subject than the respondent. Perhaps he has a "paralysis by analysis" problem, but I don't think there is a lack of knowledge.

David, I have, as well as many others, made specefic suggestion to get you going and fix the problem.

1. Basic dust collection.

2. Modify for finer partical capture.

3. Modify for pre- fan/filter dropout of heavy particals.

4. Exhaust outside with a heat exchange on make-up air.

5. Activated carbon filters on a shop air filter.

6. I will add one more note here: There is no regenerative VOC incinerator that I know of available for the home market but send me $50,000 and I will design you one.

Everything I wrote I learned since I created the thread 6 days ago.

Crank, your first 3 items are the same as my points. The difference is when you piecemeal it together you come up with in a whisker of a complete system. It is unclear how effective the HF DC is with a nano filter and effective dropout…or if a non-cyclonic dropout is sufficient to maintain the efficacy of a nano-filter.

I have nothing against HF…I have lots of HF stuff (including a $50 plunge router light enough for my wife to use and an $80 10" sliding miter saw I used this morning). My skepticism is whether the rated 2hp (knottscott says 1.6hp actual) with a 10.75" impeller has a enough juice to drive an effective separator and nanofilter the size used in those systems. You would need a meter to measure…has anyone done that?

On item 4, and this I did research for an issue with pseudo-commercial range hoods used in high end residential kitchens, there is no viable residential makeup air solution. Anything you do will make the having everyone get a ClearVue seem the low cost route.

On item 5, there are a couple of systems that have VOC catalysts. Genesis (who OEMs VOC filters to Trane's commercial division) had a residential sized unit for a reasonable price (still over $1k, but reasonable for that type of filter). The wood shop filters I've seen online from Grizzly, Delta, etc. don't have any VOC provision. A charcoal filter may help.

http://www.genesisair.com/CommercialInductPCOSystems.htm

Note: an issue in residential systems is having enough fan on/recirculation time when heating and cooling isn't required at maximum levels. The shop filters solve this my running continuously. Like residential filters, they work at a level to catch the fine particles generated by woodworking. Residential HEPA filters are run as bypass devices.

VOC's are an issue in any sealed space and are more important in today's better insulated buildings. CO2 used to be just a commercial building issue because of the higher occupancy density. Now they are also a residential issue in newer buildings.

Just to provide substance to this issue: Wood dust and sino-nasal cancer: pooled reanalysis of twelve case-control studies

Earlier Loren posted this link: Measuring dust with a Dylos air quality monitor