HEPA or Shop Vac?

I’ve been thinking I might drill out the back side of my Nomad enclosure to hook up a vacuum to collect all the waste. I primarily do aluminum and fiberglass sheet. I’d like to keep it as small as possible. What do you all recommend? A small shop vac (cheaper) or a HEPA version? I’d like to keep this in a basement craft room. Thanks!

I’m using a shop vac at the moment but I can definitely smell and find very fine particulate around my garage from what isn’t picked up.

I’ll be upgrading to a HEPA vac when my wallet allows.

I’d save your money and just go for gold.

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For most shop vacs you can find decent cartridge HEPA filters to replace the stock filter. It may be a cheap option for at least the short term.

They got down to 3 microns. Not perfectly designated as HEPA but probably much better than the normal filters you are using.

But to your point. In my opinion, you should put a dust deputy on whatever vacuum you have and you will minimize the air you are breathing significantly with or without the HEPA filter. I get almost no dust in my vacuum let alone outside in the air I am breathing and I cut a lot of MDF on my CNC.

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Couldn’t agree more on the Dust Deputy in front of the vac… I’ve noticed it takes a few seconds for the internal cyclone to spin up, and the difference in vacuum is power significant. Likewise when I shut it down there’s a “screech”.

Does anyone else experience this phenomenon that using a Dust Deputy?

I also installed the 6-layer HEPA in the Rigid Vac as well. Using 1.875" hose from the dust shoe (pictures coming of my hack, I promise) to the Deputy, then 2" from Deputy to the vac… very pleased with its efficacy.

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If you care about proper HEPA filtration (fiberglass dust is nasty stuff) I would get a vac that is EPA certified for lead. Personally I went with the dewalt DWV010 (https://www.amazon.com/DEWALT-DWV010-Extractor-Automatic-Cleaning/dp/B00OA02TZ0), which has auto clean, variable power, and power tool actuation. Other great options are fein and festool, more expensive, but have bypass cooling, and if noise is a major consideration they are quieter than the dewalt… that said all are far quieter than a shop vac (aka howling banshee).

A dust deputy or equivalent cyclone is a solid upgrade but not really necessary, especially if you get a vac with auto-clean. Its not like the nomad will fill up the vac very quickly.

This is what I did: Thoughts on a small dust collection system for my workshop?

That thread has a lot of discussion on the subject. Also, you probably want to pay attention to MBellon’s various posts on the health hazards of dust. If you’re going to be using this in an enclosed space, then personally I agree with MBellon about the importance of using a HEPA filter to save your lungs. And a Dust Deputy to extend the lifetime of your HEPA filter is a cheap investment that pays off fast – the HEPA filters are expensive.

The Nomad is nice for this since, being already well enclosed, all you really need is a hole in the back or side wall, and enough vacuum to keep negative pressure inside the enclosure – it doesn’t take much (I prop the door up 1/4" to allow for better airflow – the Nomad is almost too well-enclosed). I never got around to making a dust-collection head unit like FlatBaller designed – I just use a collet fan to blow the swarf into the air, and let the vacuum handle the airborne particles. Then, when done, I pull the hose off the back of the Nomad and use it to vacuum out any of the heavy stuff left behind. For an occasional user like me, it’s enough, but if I ever got more full-time into it, it would be fairly easy to add an internal hose and gin up FlatBaller’s design as a straight enhancement to my current setup.

I used a laser particle counter to see how good of a job its doing and the air coming out of the shop vac is cleaner (particles 0.5 microns and larger) than the ambinet air in the garage and its well within the healthy range even when collecting heavy dust loads from my SO3 router. The Nomad doesn’t make much dust so it would work even better for that. I use a Rigid brand shop vac with a homemade cyclone upstream and a bag and filter in the shop vac. I’m using the blue Rigid filter which is one level under their “HEPA” filter which isn’t really HEPA rated.

People use fear to drive decisions like this quite often. If you are working with a LOT of fiberglass, carbon fiber or other materials that have particularly nasty issues associated with the particles they produce then you might want to use a HEPA filter. You will find that certified HEPA filters are very expensive and won’t last nearly as long so its not an automatic choice everyone should make. Personally, the only time I would consider using a certified HEPA setup would be if I were cutting something that I’m allergic to. Even then, HEPA doesn’t stop everything. It stops 99.97% of particles 0.3 microns and larger. It was designed to provide protection from nuclear fallout. So, its way overkill and way more expensive than most satisfactory options for most cases. My cyclone, bag, filter setup filters 99.9+% of particles 0.5 microns and larger so its very good. The cyclone will catch 99% of particles over 10 microns but doesn’t catch much of the fine dust that you can’t see (under 2.5 microns) so really its just there to keep the filters from getting clogged quickly. The fine dust (less than 2.5 microns) is the worst because it can make it deep into your lungs so you need good filters upstream of the cyclone.

I think this is a topic that doesn’t get enough consideration by most people but it gets way too much hype by others. The best thing to do is know what you are cutting and what is required to work with it safely. Most materials pose little danger especially when run inside of an enclosure. You can breath some fiberglass or even asbestos without having life altering long term health consequences. You just have to limit the amount you breathe and keep it below safe limits. For people that work around it everyday that means very very low concentrations are allowed. If you mill something once a week inside of an enclosure and clean it up properly (decent filtration) then there’s little chance it will cause any issues unless you are allergic to it.

If you are really interested in measuring the effectiveness of your dust collection setup as well as air quality in other areas of your shop or home, you can get a Dylos 1100 Pro particle meter for around $300. The “Pro” model will measure particles 0.5 microns and up as well as 2.5 microns and up which is a common size standard used to rate air quality. Its a great alternative to $4000 particle counter machines that don’t really work much better.