CNC Routers are great. If you’ve ever used one you know this but you also know that they will cover the machine and everything around it with a layer of dust. It is certainly possible to use a shop vac to suck up the dust coming from the router, however, the only problem with that is the shop vac’s filter will clog with dust and lose suction, defeating the intent of your vac system.
[Mike Douglas] was ready to step up his CNC game and decided to make his own dust separator. This design is extremely simple and only uses a couple 5 gallon buckets, a few PVC fittings and pieces of wood. To keep the cost down and the style up, the accompanying ‘shop-vac’ is also made from 5 gallon bucket with a vacuum lid. The project is well documented so head over to his site and check out the build process.
A dust separator does exactly what its name implies, it separates the dust and debris from the air before entering the vacuum. The following diagram shows how it works: First, a vacuum creates low-pressure inside the dust separator. That low-pressure draws the dust-filled air into the dust separator. The inlet tube directs the incoming air tangent to the circular chamber. Large debris falls quickly down past the baffle and into the collection chamber. The dust enters and is thrown against the walls of the separator as it spins around. While the dust is traveling around the circumference of the separator, gravity pulls it down into the collection chamber. The now much-cleaner air then travels up through the outlet to the vacuum.
Now that we have a dust separator doing its job, would you want to stand beside your CNC machine holding the vacuum hose collecting the newly created dust? Probably not. Neither did [Gerg], and that is why he made a dust shoe for his ShopBot. It is made from scrap polycarbonate that was kicking around the shop. There are two main components of the design, the top part that attaches to the router and the bottom part that has the skirt. The bottom piece attaches to the top with magnets which allows the skirt to be removed quickly so that the tool bit can be changed easily. And in case you want to make your own dust shoe, [Gerg] has made the dxf files available.