A Sucky Topic (dust collection that is)


(Eric Stebe) #1

Hello all,

I will soon be entering into the world of hobbyist CNC with the purchase of the SO3XXL and I have been filling my head with set up ideas, enclosures, all that fun stuff.

I have jumped head first down the rabbit hole regarding proper dust collection/filtration. I have read many of the past threads discussing everything from the bare minimum to extremely complex solutions to maintaining clean air and workspace.

While I haven’t completely ruled out the possibility of buying a high-end vaccuum or an industrial dust collector, I am intrigued by the performance some of you have achieved taking the bare minimum route. I am leaning towards the shop vac (with a speed controller to dampen the sound) and a dust deputy.

My questions are more-so directed towards those of you running the following setup, but anyone with input on dust collection, please chime in:

Shop-vac with a Dust Deputy (or other cyclone separator) WITH a router speed controller.

  1. Does running the shop vac at a lesser speed/power affect the effectiveness of the cyclone separator?

  2. Does running a shop vac with a variable speed controller improve the life of the motor, since you’re not running the motor at its full potential for long periods of time.

Thanks in advance, i’m excited to get started!


(Curious in Portland) #2

I have a dust deputy, shop vac, and dust boot. I am very happy with how they perform. I would highly recommend the combination.

I don’t think much about the noise of the shop vac because it is normally drowned out by the router. I just put on hearing protection and go about my business.

I also don’t think much about the life span of my shop vac. I bought both the dust deputy and vac on craigslist. I think I paid $50 for the cyclone and $15 for the shop vac. I figured if it died I can easily replace it.


(Stuart) #3

I have the same setup as @pdx_curious with the dust deputy and suckit dust boot, but use a festool CT midi instead of the shopvac. I’ve got to say that in 3 years of 5-10hrs a week use I still haven’t had to change the bag or filter in the festool, the Dust deputy knocks out that much. Can definitely recommend this setup


(Phil Thien) #4

Cyclonic separators introduce resistance proportional to the airspeed squared.

For most smaller units, the resistance is great enough that one could likely decrease the vacuum motor speed quite a bit, without actually decreasing the airflow through the cyclone very much.


(Stuart) #5

I have seen this in practice (though I can’t quantify it). I have dialled my Vac back to almost minimum flows without significant flow or “pickup” loss. it runs very quietly at low flows


(Eric Stebe) #6

@stutaylo That’s good to hear you’re getting such great performance! Did buy the Festool as a dedicated collector for your CNC, or do you have other tools in the shop that you use it for as well? Just curious if you accredit the success to the quality of the Festool unit alone, or the vacuum + dust deputy set up combined.
I’m trying to justify buying a $500-$600 vacuum, or if a Fein or something comparable will suffice.


(Phil Thien) #7

The only real advantage to cyclonic separators, is saving bags in your DC or vac. In other words, if you vac can use bags and if you don’t plan on filling the bags at a fast rate, you’re better-off without the separator.

The only reason I added a separator to my dust collection network, is that I added a jointer and planer to my shop, which create tremendous volumes of chips. These two tools can fill my 30-gallon separator drum in just preparing rough lumber for one smaller project.

Before the jointer and planer, my table saw and bandsaw and router and sanders, etc., took quite a while to fill 15-ish gallon bags.


(Eric Stebe) #8

@cgallery gallery Doesn’t a cyclone separator also save you on having to replace/clean your filter? If the high end vacuums use expensive hepa filters, I feel like a cyclone would be a worth it.


(Stuart) #9

@stebolicious I bought the festool CT Midi for the sole purpose of dust collection on the SO3. I have a shopvac that was too loud for neighbours in the house I was living in at the time, and the festool was very quiet, and also offered a HEPA filter (also very important to me).

The festool has better suction at full power, and when on minimum speed is probably on par with the shop vac.

Is it worth it? I can’t really answer that, the festool is a lot better quality than my shopvac, it’s quieter, stronger, more compact and well built. I have heard the Fein’s aren’t too bad, and there is the option of any other vacuum with a variable speed control fitted to have it quieter. If i had my time again I’d buy the same Vac, suckit dustboot and dust deputy :slight_smile:


(Phil Thien) #10

If you are using the disposable bags, they will do more to keep your filter clean than any separator. And that is because the bags will filter fines better than a separator will separate them.

So in my workshop (and we’re going back literally decades), I started with tools that all have 2.25" to 2.5" ports on them. For me, a vac would work better than a conventional workshop dust collector.

So I got a wet dry vac, and I got some piping and blast gates, and everything worked pretty well. BUT, I did notice my filter clogged pretty quickly.

SO… I got disposable bags for my vac. Now the filter stayed clean forever and the bags were fairly easy to empty without making a mess.

BUT, then I got a jointer and a planer and was shocked at how fast I was filling those bags. It was costly and time consuming. THEN, I decided I needed a separator and started my experiments on making cyclonic separators.

If I didn’t still use a jointer and planer fairly regularly, I’d give-up the separator and reduce the resistance it imposes.

Hope that helps.


(Eric Stebe) #11

@stutaylo thank you for your input! When its decision time, Festool will be in the running.


(Eric Stebe) #12

@cgallery it definitely does help, thank you!