I’ve been thinking about building an enclosure for my MK2 for a couple of reasons. First, to cut down the noise from the router and second, to use an exhaust to pull the dust outside. My setup is in the garage, and I’ve been using my Rigid ShopVac (SO LOUD). When I’m working on the CNC, I like to hang out with friends and neighbors, but once I hit “RUN,” the noise makes it hard to have a conversation, and they usually end up leaving.
Since my machine is right next to a window, I’m considering putting an inline fan or exhaust fan either in the window or close to it, with an air duct hose connecting it to the enclosure. I’m also thinking about connecting my Dustopper to minimize the amount of chips that get blown outside and reduce dust getting into the fan.
One thing I’m stuck on is figuring out how much power (CFM) I’ll need from the fan to effectively move the dust from the enclosure, through the tubing, and out of the garage. From what I’ve seen online, I’ll need around 700-1000 CFM to push the wood chips through the cyclone and out the exhaust.
I’ve come across warnings saying not to use inline fans because they might gunk up and catch fire. However, I saw a picture on Facebook from someone who’s had their setup for some time (check out the fan in the image below). I’m hoping that with a dust separator in place, the dust and chips making it through will be minimal. What do you all think? Any advice or experiences with this kind of setup?
Below are some of the fans that I’ve had pop up during my online research. I have an idea of what to get, but I don’t have the financial luxury of buying 4-5 different fans to test which one works… I’m thinking I might just need to go with one that really creates some serious airflow (1000+ CFM).
Would recommend getting largest you can afford and fit into your space, also would recommend getting variable speed. I got an inline for laser enclosure and found the airflow dropped quickly with a bit of hose. Used an anemometer (cheap one from amazon) to measure the flow.
If it is just connected to the enclosure I wouldn’t expect it to remove any chips, suction has to be closer to the source, would be for airborne particulates. It would be prudent to routinely clean the hose/ducting.
I installed an exhaust fan in my shop when I built it in 2020. This fan moves a LOT of air! So much that I must open a window or door in order to allow the fan to work well. Here is a picture of what I bought. It is strong enough that I don’t really think this type of fan is what you are seeking. You would burn out the motor from all the draw. I ended up putting a door in the inside of mine. The shutters rattle and allow a lot of cold air into the shop.
With any of these fans, you need to provide fresh air for the air being removed by the exhaust fan.
Have you thought of obtaining an inexpensive dust collector? Mine is very quiet and does a decent, but not great job of collecting dust.
I did just purchase an actual air scrubber for the shop. It will hang from the ceiling. I got sidetracked and haven’t been out there to install it yet. SHOULD be a decent addition to reduce airborne particles.
An inline fan might be effective for DUST particles (ie anything that floats in the air) but you will not be happy with it’s performance for even tiny chips. Also, these fans are designed to have very little pressure differential between input and output and any length of hose will quickly kill any flow that existed without the hose.
A squirrel fan design might overcome a tiny bit of hose but you will still not be happy.
Do it right the first time instead of doing it multiple times.
You could tackle this with a different approach - try and reduce the noise of the shop vac (have plenty of air flow for cooling though)
If the induct fan is to clear the enclosure from floating dust, may I suggest an out of the box solution that might work pretty well for a small enclosure.
A kitchen extractor.
I use one of these above my office workbench where I do some solder work and small paint jobs. They work well, are relative quiet, not that expensive, extract air over a wider range than a duct, have some filtering (foam stuff) and come with led lights which is nice.
I only use mine on the lowest possible setting for it only needs to extract fumes and it’s way to powerfull when in higher modus. (Long hair standing upright powerfull.)
If used in an small enclosed space, it will suck it into a (no where) near vacuum.
Good point about the airflow drop with longer hose runs. A variable-speed option sounds like a great idea for control. I’ll definitely look into an anemometer to measure flow. But hadn’t thought of that!
Turned out I mostly needed to run at highest speed to counteract the reduced airflow, but lower speeds were a nice option to reduce noise while still maintaining a negative air space inside enclosure.
I have never been much of a Dewalt person (for no particular reason ) but people should take a look at Dewalt’s STEALTHSONIC shop vacs. They are amazingly quiet. They are a bit more expensive but they have great suction and are some of the the quietest tools I have in my shop (hard to believe but true). I have one permanently connected to my CNC (with a relay) , one permanently connected to my random orbit sander (with a relay), and then one other for anything else around the shop.
) but people should take a look at Dewalt’s STEALTHSONIC shop vacs. They are amazingly quiet. They are a bit more expensive but they have great suction and are some of the the quietest tools I have in my shop (hard to believe but true). I have one permanently connected to my CNC (with a relay) , one permanently connected to my random orbit sander (with a relay), and then one other for anything else around the shop.