Shop Vac Filters - NEVER have to clean your shop vac filter again with this DIY system!

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​In this article, you will learn how to build a shop vac system that...

• Never requires you to touch the filter again
• Improves the   filtration efficiency of your vac system
• Allows you to mount your vac out of the way to reduce noise

Plus...

• How cyclone separators work
• Why a cyclone separator is not enough to create a maintenance free system
• The differences between shop vacs and dust extractors

Shop Hacks articles are designed to empower you to Build Your Space so they are longer than most but, if you prefer to skim...   Use this index  to  go straight to the parts you care about ...

1. Cleaning a shop vac filter exposes you to the dust you want to avoid
2. What if I told you that you never have to  clean  your shop vac filter again?
3. How do I know this system is safe?
4. Why don't manufacturers make all shop vacs this way?
5. ​What's the secret to NEVER having to clean your shop vac filter?
6. Benefits of never having to touch your shop vac
7. How to build your own maintenance free shop vac system
8. Shop Hacks maintenance-free shop vac   system   recommendations
9. Deep Dive - More options and more insights for the curious...

• How do cyclone separators   work?
• Do you still need to use a filter with a cyclone separator?
• Shop vac cyclone separators  options?
• How to make your own cyclone separator.
• Choosing a collection bin
• Choosing a shop vac
• Shop vacs vs. dust extractors - is there a difference?

1.  What if I told you that you never have to  clean  your shop vac filter again?

​This is a picture of my 3-year-old shop vac filter that has never been cleaned.   It has over 700 hours of vacuuming CNC router (a tool that cuts wood all day long) dust from various types of woods and composites and it still works like new.  As you can see, the filter has very little dust in it.  Even after 700 hours of use  it still flows air like it did the first day.  

2.  Cleaning a shop vac filter exposes you to the dust you want to avoid.

Who likes having to clean your dirty shop vac filter?  You take it out, hold your breath and beat it on the ground and/or blow it out with compressed air and install it back into the vacuum.  You end up wearing and breathing the dust that you bought the filter to protect you from in the first place! Not to mention, there's never a convenient time to clean a shop vac filter.   It always  needs to be cleaned in the middle of a job.

3.  How do I know this system is safe?

Not only have I never had to clean or change my filter, it  still cleans my workshop air as I'm using the vacuum.  Even when I'm vacuuming fine dust from cutting MDF, the air  quality  in my workshop (measured by a Dylos DC1100 Pro laser particle counter)  remains in the "very good" range and particle counts do not rise at all.  If you want to save a few dollars and don't mind buying somewhere other than Amazon then click HERE for more options and  a  lower price.  That's not an affiliate link but the price  difference is enough that I want you to be aware of it.

​​Do I have your attention?  Keep reading and I'll show you how you can do the same thing with just a few components.

4.  Why don't manufacturers make all shop vacs this way?

You might ask yourself, "If there's a way to design a shop vac so that you never have to clean a filter again then why don't the manufacturers design shop vacs this way?".  The answer is simple.  It is very similar to the situation with home vacuum cleaners 20 years ago... the technology to make home vacuum cleaners bagless had been around for many decades but it was more profitable to sell bags than it was to sell bagless vacuum cleaners.  It wasn't until Dyson gained enough market traction with his bagless "cyclone technology"  vacuum ​ that manufacturers were forced with a decision to either fall behind or adapt their vacuums to consumer demand.  Dyson integrated a 50+ year-old technology into home vacuum cleaners and totally disrupted the entire market.

In the same way, workshop vacuum manufacturers make a lot of $$$ selling filters.  The technology has been around for decades to make a shop vacuum that never requires the filter to be cleaned but manufacturers won't be willing to change until someone disrupts the market with  a product that forces them to give up their cash cow... new filters!  It appears that focus on profits outweighs concerns to offer customers the best product possible.  Although some shop vac manufacturers are starting to integrate cyclones into their systems,  the practice hasn't become widespread yet.

So, how can you beat the system and save some $$ in the process? 
​5.  What's the secret to NEVER having to clean your shop vac filter?

You will need 5 components to build a maintenance free vacuum system .  If you don't include all 5 components you will continue to have to clean your shop vac filters.  With all 5 working as a system you will never have to change the bag or clean the cartridge filter.  That opens up some very interesting possibilities that you might not consider otherwise.  Since the vac, bag and filter are all in one unit and will never need to be accessed, you can mount the vac in a remote location such as up in the rafters, in a ventilated cabinet or closet, or even outside in a weather resistant enclosure.  

6.  Benefits of never having to touch your shop vac

The most obvious benefits to never having to clean your shop vac filter again are...

• You save time and money
• You don't have to breathe or wear the dust that you bought your filter to protect you from in the first place

However, there are some non-so-obvious benefits to this setup.  With a system that doesn't require you to touch your shop vac, except to replace it, you open up the possibilities of mounting the vac system wherever you want.   Your vac no longer needs to be mounted close to the cyclone separator.  That freedom allows MANY more mounting options for each component. 

For instance, you can mount your shop vac...

• in the attic
• in a ventilated cabinet or utility room
• outside of your workshop
• from the ceiling in an unused area

Simply plumb 2.5" or 3" PVC pipe from the vac to wherever you mount your cyclone separator and waste bin.   If you have a run over 20' then use 3" DWV PVC.  Otherwise, 2.5" will work without affecting the flow rate noticeably.  The waste bin may be mounted on a wall so that it is convenient to  access when it needs to be emptied.    Since the waste bin is independent of the vac, you can use anything from a 5 gallon bucket to a 55 gallon drum.  More about that later.

Caution...
Shop vacs create as much heat as portable heaters so always make sure you mount your vac in a well ventilated  space to allow prevent overheating.

If you build your own creative combination then be sure to share a picture of your setup in the   Shop Hacks Facebook group  so everyone else can see it too!  The Shop Hacks Facebook group is a great place to share and to see other's solutions too.

7.  How to build your own maintenance free shop vac system

​​The figure below illustrates the 5 components needed to build a maintenance free system.    ​ If some of this is new to you, don't feel intimidated.    Putting this system   together   is very easy.  You just purchase any of these components that you don't already have and connect your shop vac hose to the cyclone separator, connect a new hose to the inlet of the cyclone separator, install a bag filter, and you are finished!

There are many ways to configure the system but this is what the full system may look like. 

Some people mount everything on a rolling cart with the dust bin and cyclone at the top.   I recommend placing the shop vac in the rafters or in a utility room then running  2.5" to 3" PVC pipe from the vacuum to the cyclone separator  which may be mounted on the wall.  That will allow quiet operation of the vacuum while still  having a convenient way to empty the  collection bin. 

Using the remote power switch I linked to earlier means you never have to touch the vac again.  I attached the power switch  remote fob near the end of my vacuum hose so anytime I want to use the vacuum I just press the power button  near the end of the hose and I'm ready to roll.

The following overview below describes each component in more detail.  If you would like to see  several options for the various components and learn more about how they work then be sure to read the Deep Dive section later in this article.

1.  A cyclone separator  that is designed for a shop vac system
The cyclone separator  is where most of the magic happens. A cyclone separator that is properly matched to the vacuum it is connected to will remove 95% to 99% of the dust from the air stream. That means the bag and filter only have to remove the fine and very fine dust particles.    However, a cyclone alone is not enough to prevent clogged filters.

Most of these cyclone separators will connect to a standard 2" ID shop vac hose.  Some come with an extra hose to connect to the inlet of the cyclone (the hose you use to clean up messes) and some do not so check the details to see if you will need to buy the extra hose or not.

2.  A collection bin
95+% of the dust and debris that enters the cyclone will fall into the collection bin below it.  You can use anything from a 5 gallon bucket to a 55 gallon drum for this.  It has to be able to withstand the vacuum pressure of the  vac and  it must be sealed air tight.   It needs to be sealed air tight and it has to withstand the vacuum pressure a blocked vac hose can produce (up to  500 lbs per square foot). 

If you are careful to not block the hose to your shop vac then just about any 5 gallon bucket will work.  Just mount the cyclone separator to the sealed bucket lid per the instructions, or just put it on the bucket in the case of the Dustopper, and you are ready to go.  If you have a powerful shop vac it can cause the bucket to buckle if the hose gets blocked off more than a second or two.  To prevent this you can cut out a 3/4" thick by 1" deep plywood ring using a jigsaw or a bandsaw and then press it inside of a 5 gallon bucket to prevent it from collapsing under the vacuum pressure of a strong shop vac.

3.  A filter bag
The shop vac filter bag is the key component that most people aren't aware exists or don't think to use.    Normally it would be quite expensive to use bag filters on a shop vac because the bags would fill up very quickly.  However, if you use a cyclone separator upstream of the bag, the bag only gets 1% to 5% of the debris which means it will last the full life of the vacuum without requiring replacement and it prevents your cartridge filter from clogging.

The filter bag captures small particles that would eventually fill the cartridge filter downstream.    With a bag in place the cartridge filter only has to capture the very fine particles that pass through the bag.   That extends the life of the cartridge filter  for the life of the shop vac.  I suggest using a relatively cheap filter bag since you will be depending on the cartridge filter to capture the finest particles downstream.  A cheaper filter bag  is less likely to clog over time since it it passes the finest particles.

4.  A quality cartridge filter
Cheap filter bags don't capture the finest and most dangerous dust and that is fine because we want to depend on a quality cartridge filter to do that job.  Many shop vacs come with quality cartridge filters but some do not.  Make sure your vac has a quality filter so that it doesn't pass harmful fine dust into your workspace.  The most dangerous dust is  too small to see with the naked eye so you have to rely on the performance of your filter.

5.  A vacuum that flows between 100 and 200 CFM.   
Choose a vacuum fits your budget and preferences and  that has at least 100 CFM  of airflow.    I recommend not using anything with less than 150 cfm for general shop cleanup.  If the manufacturer doesn't say how many CFMs the vac flows just look at the amp rating for the motor.  Anything over 12 Amps should work fine.

Disclosure
I am not sponsored by any company so you can be sure that all of the recommendations in this article are unbiased.  I base my recommendations on systems that I use myself and that I've tested and proven to work.  The links in this article are affiliate links.   If you buy products with these links you will pay the same price that you would pay without using the links and Shop Hacks will receive a small commission.  I hope you benefit from  these articles and I thank you for supporting more content like this by using these links for any product that you are interested in purchasing.  Thank you!

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8.    Shop Hacks maintenance-free shop vac   system   recommendations

 If you want a tried and tested system without  reading the rest of this article then you can click images below for the products I personally use and recommend.  I have tested these products and  I can assure you that my setup is very effective.  This is not the cheapest  nor the most expensive system you can buy but it will move more air than most  $700 vacuum systems and I've verified that it does a great job of removing harmful dust from the air.  I have used this system for more than 700 hours (a lifetime of operation for many users) and it still works like new with the original cyclone, vac, bag and filter.  The bag is still less than 1/4 full.
​
​The components I use and recommend:

1. The Dust Sheriff DIY Standalone Cyclone Separator     ($9.95 for plans)
2. A Home Depot or Lowes 5-gallon bucket or   5-Gallon Bucket with Sealed Lid   ($8 amazon)
3. Ridgid VF3502 High Efficiency, Dry Pickup Dust Bags for 12 - 16 Gallon Ridgid Wet / Dry Vacuums   ($18.97 Amazon, 2 Pack)
4. Ridgid VF6000 Genuine Replacement 5-Layer Allergen, Fine Dust, and Dirt Wet/Dry Vac Filter for Ridgid 5-20 Gallon Vacuums    ($29.95 Amazon)
5. The Ridgid WD1450 14-Gallon 6-Horsepower Wet/Dry Vacuum   ($188 Amazon)​​

If you prefer to research more options to make a more informed decision based on your personal preferences vs. mine, I will go over each product in detail the Deep Dive section.  The Shop Hacks recommended system consists of the five components previously mentioned.

1a.  The Dust Sheriff DIY  Cyclone Separator   ($9.95 for plans)
After testing the Dust Deputy and the  Dustopper I designed  a cyclone that you can build yourself in under an hour .  The Dust Sheriff flows 30% more air than the Dust Deputy and separates 5x more fine dust (corn starch used for testing).

The Dust Sheriff is also the only cyclone separator that includes an optional integrated filter inside the cyclone housing.

1b.  The Dust Deputy DIY Standalone Anti-Static Cyclone Separ ator   ($50 Amazon)
I bought the Dust Deputy because it was the only mainstream shop vac cyclone available when I was researching this topic.  I have tested the Dust Deputy and it removes over 95% of very fine dust like corn starch.  It removes closer to 98% of most dust produced by common equipment such as routers , table saws and the like.  It removes 100% of larger particles such as chips from a planer.    It doesn't perform as well as the Dust Sheriff but it is a solid choice for anything but the finest dust.

There are more expensive and cheaper models from different brands available.  I will cover them in a following section.  They are all about the same efficiency give or take a few percent.

1c.     Dustopper High Efficiency Dust Separator, 12 in. dia, with 2.5 in hose, 36 in. long  ​($48.75 Amazon, $40 through Home Depot)

I haven't personally used or tested the Dustoppper but I feel comfortable recommending it because I've designed and tested several cyclone separators just like it.  I include it in my recommendations list because it has one specific advantage over the Dust Deputy... it has a much lower height allowing the vacuum hose to connect much lower to the ground.  This  makes it  more stable than the Dust Deputy which is very unstable unless you have it mounted to a cart or some other stable structure.

The Dustopper is likely slightly less efficient  when it comes to removing very fine dust such as drywall or  wood sanding dust.    If you plan to use your cyclone for a lot of very fine dust applications then use the Dust Deputy or one of the other cone shaped cyclones.    Otherwise, the Dustopper should work great.  If you  like the low profile of the Duststopper or the lower price then it is a good choice for most situations.
​

2.  A 5-Gallon Bucket with Sealed Lid   ($8 Amazon)
You will need a receptacle under the cyclone to catch most of the dust and debris.    You can use this link but if you live near a Home Depot or Lowes you can find  buckets and lids cheaper there.


​

3.  Ridgid VF3502 High Efficiency, Dry Pickup Dust Bags for 12 - 16 Gallon Ridgid Wet / Dry Vacuums   ($18.97 Amazon, 2 Pack)
This is the bag that I use.  I suggest NOT using a high efficiency bag since the shop vac cartridge filter will handle the very fine particles and a high efficiency bag is likely to clog up before the end of the life of the shop vac.  This link is for a  2-pack of bags.   You probably won't need the second bag but if you get into vacuuming very fine dust, like drywall dust, it is possible you may need to replace the bag at some point so a having a second bag is handy.
​

4a.  Ridgid VF6000 Genuine Replacement 5-Layer Allergen, Fine Dust, and Dirt Wet/Dry Vac Filter for Ridgid 5-20 Gallon Vacuums    ($29.95 Amazon)
This filter is made from HEPA rated material.  That means the material will capture 99.97% of all particles 0.3 microns or larger.  I recommend this filter if you frequently vacuum particles that you may be sensitive to.  This is Ridgid's  highest rated filter.  You will lose a small amount of flow rate over time using this filter but it won't be noticeable and this filter offers a high level of protection.

4b.  Ridgid VF5000 - 3-Layer Pleated Paper Vacuum Filter   ($21.89 Amazon)
This filter is rated slightly lower than the VF6000 but I still didn't detect a rise in particle counts in my shop while using it so I recommend this filter if  you would prefer a slightly higher flow rate with a slight reduction in filtration efficiency.  Either of these two filters will work well.

​

5.    The Ridgid WD1450 14-Gallon 6-Horsepower Wet/Dry Vacuum   ($188 Amazon)
​ I like this vacuum because it flows more air than  most shop vacs that cost 3x as much (200 CFM vs 150 or less).  It has a foam liner around the impeller housing (Scroll Noise Reduction Technology) which reduces the high frequency noise  which makes it much easier on the ears.  I would not call it "quiet" but it doesn't have that annoying high pitched whine than most shop vacs have.  I have over 700 hours of use on mine and it is still running like new.

​

Power Tip to make your system completely "no touch" .  ($11.99 Amazon)
By adding a remote power switch you can turn the vacuum on and off even if it is mounted out of reach.  I use this switch which is rated for up to  15 Amps.  I've tried other remote switches that all eventually failed within 6 months or so.  This switch has lasted well over a year now.

Think about the possibilities now that you don't have to worry about emptying your vac anymore.     Just run a flex hose from the vac to some 2.5" or 3" PVC to the top of the cyclone separator and collection bin which can be mounted on the wall.

9.  Deep Dive - More options and more insights for the curious...

If you want to   understand how each component works as well as more of the  options available then you are in the right place.  In this section we will discuss each component in more detail and I'll list  several popular options  for each.

How do cyclone separators   work?

Using a cyclone separator is essential to never having to clean your filter again.  ​At 99% efficiency  you will have to vacuum 1400 gallons of dust before you  fill a  14 gallon shop vac bag.  Trust me, the vac will die long before you  reach that mark.

​Cyclone separators come in a huge variety of shapes and sizes.  They range from as small as your finger to larger than a house.  They are always used to separate heavier than air  materials from an air stream.  

To understand how a cyclone separator works, picture a marble entering at high speed into the cyclone inlet shown in the figure below.  As you can imagine, the marble will stay pressed against the outer wall of the cyclone and gravity will pull it down the wall until it falls into the receptacle below.  As it moves down the cone it naturally starts spinning faster which increases the g-forces which pulls it even harder against the wall.  Now picture that marble traveling with a flow of air into the cyclone inlet.  The air will also swirl around the cyclone but it  is pushed out through the cyclone outlet as new air is pushed into the cyclone inlet.  So, the marbles, which are heavy, follow the wall down into the receptacle below and the air flows out the cyclone outlet.

This configuration separates particles from the air stream remarkably well.  I've designed and tested many cyclone separators over the last few years.  The Dust Deputy cone type cyclone is similar to the one shown above.  In my tests the Dust Deputy removed around 95% of fine corn starch powder, 98% of most sawdust particles and 100% of all chips.     I developed several  variations of a Thien Baffle design, similar to the Dustopper, and the best of those designs performed  within the experiment margin of error compared to the Dust Deputy.    Based on my experiment results from similar systems I would expect the Dustopper to capture slightly less than the Dust Deputy for very fine dust but it should perform equally well for larger particles.  In any case, unless you are vacuuming drywall dust or some other super fine dust, either of these two systems should suffice.

Do you still need to use a filter with a cyclone separator?

Several years ago I designed a cyclone separator that worked so well I could vacuum sawdust without a filter and I could not see or smell any dust coming out of the vacuum.  I was pretty excited about that design.  After I bought a   Dylos DC1100 Pro laser particle counter   to see how well my dust collection systems were working I was shocked to find that when I used that vacuum the dust concentration  in my workshop  air  increased over 20x to levels  4x maximum safe limits.  I was shocked but it was a great lesson that using an air quality meter is essential  if you really want to know if your air is  safe or not.

ALWAYS use a high quality filter downstream of any cyclone separator.  The figure below illustrates how cyclones work well to remove   particles over  10 microns but they pass  most of the particles  under 2.5 microns which are the particles that travel the deepest into your lungs and into your bloodstream.

Shop vac cyclone separators  options?

Shown below are 5 common models of cyclone separators designed for use with shop vacs (flow rates between 100 and 200 CFM of air).  You can click on any of the photos to be take to  a page with more details about each cyclone.  They are all basically the same conical cyclone design except for the Home Depot Dustopper.    The Dustopper is a Thien Baffle design which is slightly less efficient and is about 8" shorter than the others which makes it much better for any type of mobile or height restricted application where the cyclone and dust bin are not attached to a stable structure.  With the conical cyclone separators,   you pull on the hose which is attached 12" above the  dust receptacle which  will easily tip many designs over.  The  hose for the Dustopper mounts about 2" above the dust receptacle making it more stable.

All of these products will have similar performance characteristics except the Dustopper will be less efficient at separating fine dust.  If you are planning on collecting drywall dust or a lot of sanding dust then it may not be the best option.

Click on any of the images above to go to the associated product page.

For proper performance you must use a cyclone designed for the flow rate of your vacuum 

Always match the cyclone to a vacuum or blower that falls within the design  parameters of the cyclone.   Since few of the cyclone separator manufacturers list the CFM range their products are designed for this isn't always possible.  In any case, you should be able to use any of the cyclone separators listed in this article with any vacuum that flows  100 to 200 CFM.

If you connect a cyclone designed for a shop vac to a dust collector it will reduce the flow to almost zero and the cyclone won't  separate the dust efficiently.    If you use a very small vacuum with less than 100 CFM of airflow with a shop vac cyclone separator   you will find that it still works well for chips and large dust particles but it will pass a higher percentage of very fine dust.

An option that may be useful in some situations is to connect the outlets of multiple cyclones to a single manifold.    For instance, you could connect 5 of these smaller shop vac cyclones via a manifold to a 600 CFM dust collector.    I can't think of any situations where that would be worth the trouble but I bring it up in case it spurs some ideas in any of the creative types  reading this article.  Oneida offers the  system shown below.  It allows the use of two vacuums connected to three cyclones via a manifold.

How to make your own cyclone separator

​It is not difficult to fabricate your own   conical cyclone or Thien baffle cyclone system.    You can click on the hyperlinks to find out more about each.

Choosing a collection bin

The most important  things about your collection bin...
1.  It needs to be strong enough to withstand the maximum pressure created when your vac hose is blocked.  
2.  It must be air tight or the cyclone will pass more dust than it would otherwise.

Most full size shop vacs can produce a vacuum pressure of around 3.5 psi which is about 500 lbs per square foot.  That means that if you have a 12"x12" top on your collection bin, it will have to be able to support a 500 lb weight evenly distributed across the top without collapsing.  The forces produced are huge and they are proportional to the area that they act on.  That means that the walls of a large collection bin will experiences forces much higher than those of a small collection bin.

​Prevent implosion with a simple fix - My shop vac can easily implode any 5 gallon plastic bucket and most trash cans.  To avoid this problem I cut out a plywood ring  to a size that allows it to press fit about halfway down the bucket.  This adds just enough strength to the bucket to prevent it from collapsing when the hose gets blocked.

It is very important that the  collection bin does not leak any air.  Any air that leaks into the collection bin will  flow from the bin and up through the center of the cyclone and out the top of the cyclone.  That air will carry  dust that is circulating in the collection bin which will greatly reduce the efficiency of the cyclone separator.

Choosing a shop vac

-Most  shop vacs flow within the 100 to 200 CFM range.  Manufactures often do not say how many CFMs their vacs flow, but if you look at the amp rating for the motor you can estimate flow rate using the following formula: 

Flow rate =  Max Motor Amps x  16   (for a rough estimate)
I.E. a  motor rated for 11 amps will flow about  11x16 = 176 CFM. 
A motor rated for  6 amps will about to    6x16 = 96 CFM.

This calculation  will not be accurate for every  shop vac but it will get you close if the manufacturer of your shop vac doesn't list the flow rate in their marketing materials.  Most vacs have the motor amps listed somewhere on the vacuum itself.

Typical full size shop vacs pull around 11 amps which equates to between 150 to 200 CFM depending on the overall efficiency of the vac system.  A small shop vac may pull closer to  6 amps which equates closer to 100 CFM.

​Many shop vacs come with quality filters.  However, some come with very cheap filters that catch visible dust but pass almost all of the most harmful very fine dust.  Very fine dust can travel the full extents of your lungs and reach your bloodstream where it can cause inflammation which is the trigger for many types of diseases over time.  I've only tested the Ridgid brand shop vac filters and I can recommend their top two tier filters because I didn't see any increase in particles 0.5 microns and larger in my workshop while vacuuming fine dust with either of those filters installed.  To protect your long-term  health, only use filters that are rated to capture sub micron particles  with  high efficiency.    If you use the advice offered in this article you can spend more money on your filter because it will now last the entire life of your vacuum.

Shop vacs vs. Dust extractors - is there a difference?

There are endless debates about the value of expensive "dust extractors" compared to the common shop vacuum.  There  are reviews that extol the wonderful magic powers of dust extractors  and  they  lead you to believe that anything less is taking a chance on your health.  Fein and the Festool are two    of the most common dust extractors on the market.

Fein dust extractor

​Festool 575267 CT MIDI HEPA Dust Extractor

What's the difference?  Is a dust extractor worth  double to 5x the cost?

If you take a shop vac, a dust extractor or even a common house vacuum apart you will find that they all use very similar components.  They all have the following major components...

1. A brushed motor with a closed impeller to pump air.  Typically around 1200 Watts with a free flow rate of around 150 to   200 CFM and produce between 3 to 4 psi of vacuum when the hose is blocked.
2. One or more filters
3. A bin to collect the dust and debris

Extra features that dust extractors have that most shop vacs do not have:

1. Noise suppression
2. Speed control
3. A more efficient form factor
4. Most "extractors" use quality bearings and brushes for their motors.  Some shop vacs do and some do not.
5. Auto start power receptacles

Most shop vacs and extractors these days offer quality filters and very good seals to ensure that dust does not bypass the filter.  So, is it worth it to spend 2x to 5x as much to get a dust extractor?  The answer to that question is, "it totally depends on what you value".

What a dust extractor will not do better than a quality shop vac:

• Filtration.  If you use the setup I recommend in this article and you are NOT vacuuming toxic materials then a shop vac will offer enough filtration to prevent detectable increase in the particle counts in your work area (for particles >0.5 microns).  If you are vacuuming toxic materials  then you need to invest in a certified HEPA vacuum.  
• Flow Rate.   Most dust extractors flow around 150 CFM and use 1.5" hoses  which are much more restrictive than the 2" ID hoses used with most shop vacs.    The Ridgid  shop vac I use flows closer to 200 CFM.  You will see reviews comparing which vac sucks up water the fastest or how high it will raise a ball in a tube but, honestly, how often do you use your shop vac  to suck up water or to lift balls in the air?  Those tests are designed to favor  particular vacuums.   The only thing that really matters is how many CFM does your vacuum flow in the configuration that you use it in 80% of the time.   Some dust extractors use motors that produce 20% more pressure when the hose is blocked.  This extra pressure may help when connected to tools with very small dust ports (less than 1" ID) but it creates a lower maximum flow rate when the tool is used with an open hose.  Either way, you won't notice a very significant difference between most dust extractors and most full size shop vacs in terms of pressure or flow rate.
• Noise Level.   This, in my opinion, is the single most beneficial feature of dust extractors vs. shop vacs.  The two dust extractors  listed above operate at a very comfortable noise level with no annoying high pitched whine.  They include a speed control that allows you to turn the speed of the vacuum motor down which lowers the noise level even more.
• Auto-start power plugs.   Dust extractors include  auto-start power plugs that turn  the vacuum on when you start  a tool that is plugged in.  This is handy for tools like sanders because you don't have to turn the vac on and off each time you turn the tool on and off.  Everything is automatic.  For some work flows this could be a very valuable time saver.  You can buy such  plugs for a shop vac  too to make it work the same way.  One caution... most of these vacs draw around 11 amps  from a 110 VAC outlet.  That only leaves a few amps more until you reach the limit of a 15 amp breaker.  You can get by running a sander and the vacuum on the same circuit as long as there are no other significant power draws on that circuit but you may find yourself kicking a breaker otherwise.
• Durability.   I've talked to a lot of people who swear their shop vac died a painful death after just a year of light use and there are others who claim that the vacuum their great great grandfather brought from Germany is still running like new  (joke ;-).   I can tell you that my shop vac has over 700 hours of use and it is still running like new on the original bag and filter.  There are differences in motor bearing and brush quality so it is hard to say which models will provide more life.  I think it is safe to say that the very best vacuum motors should not be expected to operate more than 1000 hours before the brushes wear out or the bearings fail.  To date, no one that I know of uses brushless motors in their vacuums.  When they do you can expect the vacuum to last at least 6000 hours before the motor wears out.  It is bound to be on the drawing board by now.
• Ergonomics.  This is another area where dust extractors have a significant advantage over shop vacs.  They are designed with  a rectangular form  factor that makes them more volume efficient .  You can easily store a dust extractor in a small space .  The Festool system also allows stacking of storage containers on top of the vacuum which is very helpful to some users.  Shop vacs are still manufactured in a cylindrical geometry for some reason.  Maybe manufacturers will wise up one day and stop throwing away over 20% of the capacity they could have if they made  designed their units with a rectangular form factor.

As you can see, there is a reason that the market supports both types of vacuum systems.    The one that works best for you may not work best for me.    Now you know the differences and won't have to believe that extractors have magic powder sprinkled on them to make them and their owners superior to  all others ;-)

I would love to hear from you.  Please don't be shy.  Post  questions or comments  in the comments section below.     Leave a comment to let me know what topics you would like to see covered in future articles.

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