How to Control and Collect Dust from a CNC Router


If you are a new owner of a CNC router, purchase and assembly are only the first steps. Without proper maintenance, your woodshop will be plagued with dust particles that will harm your power tools and your lungs. So how can you control and collect dust from a CNC router?

To control and collect dust from a CNC Router, there are various methods you can rely on. Shop vacuums are appropriate for cleaning immediate messes. However, the CNC router requires a dust collection system that will extract smaller particles from your tool and the air.

Moving forward, we will guide you through managing dust from your router. More specifically, we will focus on assembling a dust collection system that suits your needs. Once you’re ready to assemble your system, check out our product recommendations at the end.

Control

Dust Collectors and Shop Vacuums

It is a common misconception that dust collectors and shop vacuums are the same. While both tools control dust particles in the woodshop, they differ in the size of material they handle and the area of space in which they are used.

  • Shop vacuums work like high powered vacuums. Using a wide-ranged hose, shop vacuums can suck up small to medium wood chips and sawdust particles. Then, a filter system collects the debris. This is good for cleaning concentrated dust piles that develop after working.
  • Dust collectors, on the other hand, collect the smaller particles that shop vacuums cannot. Using a more sophisticated system, dust collectors quickly clean up wide areas of dust and small materials. Once the dust is collected, bigger materials, like nails and wood chips, are filtered from the smaller particles. Dust collectors cover the range and particle size that is necessary for running a woodshop with a CNC router.

Depending on the scale and needs of your woodshop, you will install the following peripheral attachments to your dust collection system.

Installing Ducts

Ducts are the pipes and hoses that transport dust and particles from your power tools to your dust collector. Basic dust collector sets usually come with an extendable hose that will connect with your appliance. However, if you are using multiple tools in your shop, you will need to construct a system of ducts that connect to your collector. Think of them like a sewage system, but for air.

When installing your ductwork, consider these connectors to seal your passageways and prevent air leakage.

Avoid permanent connectors, like adhesives. You will need malleability if you plan to accommodate other tools in the future.

Steer clear of connections that extend beyond a 90° angle. Perpendicular and sharp angles will increase static pressure and inhibit airflow.

If you’re looking for an example of DIY ductwork, check out Rag ‘n’ Bone Brown’s system below:

Grounding Ductwork

Grounding PVC or other plastic ductwork is not necessary, but you might find your shop more pleasant if you do.  The tiny wood chips and dust rubbing up against the plastic will eventually build up a static charge.  This charge might give you a shock occasionally as you brush by the ducts. This static charge is small and will not cause anything to ignite. 

More on PVC and static electricity can be found in this article.

There are several grounding kits available if you care to investigate them.  A few tips when installing a ground wire to your PVC ductwork:

  1. Secure the ground wire to the PVC duct using screws.  PVC is an insulator so the static buildup will not travel through the walls of the PVE very fast.  The screw will help capture the static and transfer it to the ground wire.
  2. There is no need to wrap the ground wire around the entire diameter of the duct.  Alternating sides with the screws and connecting the ground wire back and forth on the underside of the duct is sufficient. 
  3. Use short, fat screws.  Just long enough to penetrate the wall of the duct without being so long as to snag chips and debris as they travel through the duct.
  4. Secure the ground wire to the metal enclosure of the dust collector when you are done adding the ground to all the ducts.  The motor is grounded through the enclosure so this will provide a path to ground for your entire collection system.
  5. Grounding kits and bulk copper wire:

Installing Gates

Blast gates manage the airflow between your various tools and your dust collector. They are valving that open or close to achieve the greatest suction power at your desired tool station. It is best to place them near the ductwork connecting your power tool.

There are many kinds of blast gates. Automatic gates provide ease of operation and can often be controlled remotely. However, you can order a mechanical gate or even make your own.

In this video below, for example, Rag’ n’ Bone Brown constructs manual blast gates using plywood:

Dust Boot (for CNC Routers)

A dust boot is a bristle vacuum that connects to your dust collector and operates from your router. If you are feeling adventurous, you can even make your own dust boot using your CNC Router!

Avid CNC features a Universal CNC Dust Shoe in their Design and Make Project Series.

For more info, check out the instructional video below:

Collecting

2 Stage Modifications

There are two kinds of dust collectors, single-stage dust collectors, which are best for small shops, and 2 stage cyclone dust collectors, which utilize a multi-compartment system that benefits larger shops. However, smaller shops can have 2 stage systems sized correctly for the available space.

As you expand your woodshop, you may realize that your single-stage dust collector can no longer meet the demands of your space. However, there is no need to trash it. Instead, modify your single-stage collector into a 2 stage collector by connecting a second airtight compartment.

Here is an instructional video to get you started:

CFM Consideration

As you assemble your air collection system, it is important to consider CFM or l/s.

CFM (Cubic Feet per Minute) or l/s (Liters per Second) measures the volume of air that a device can move from its intake to exhaust in a given amount of time. In order to create the necessary linear air velocity for maximum dust collection, the CFM or l/s of your dust collector must meet or surpass that produced by your tool.

Wood Magazine states that a table-mounted router generally produces 195CFM or 92 l/s. Therefore, your dust collector must, at least, meet the same specifications. However, if your woodshop contains tools that produce a higher CFM or l/s, you should plan accordingly.

Dust/Chip Separation

Dust/chip separation will protect your dust collector filter from abrasion caused by large particles. 2 stage dust collectors are designed with this in mind. In fact, you can facilitate dust/chip separation by using the 2 stage modifications mentioned above.

But did you know you can create a dust/chip separator using containers from your own house? Consider J Phil Thien, who created  The Thien Cyclone Separator Lid w/ the Thien Cyclone Separator Baffle to transform his trash can into a workable cyclone separator.

Products

Designing a dust collection system for your CNC router can be intimidating at first. Luckily, we found these great products to help you get started!

Final Thoughts

In short, cleaning and collecting dust from a CNC router requires more than a shop-vac. A proper dust control system, including a dust collector, ductwork, blast gates, a dust boot, and a separator is ideal. You can modify your system as your woodshop changes. However, your system must always produce the same amount of CFM or l/s as your router.

Sources

John McCormick

I have been woodworking since being introduced to the hobby in High School. I enjoy woodworking as a hobby and would like to share some of what I have learned with the world. I have recently built a CNC router system and I have enjoyed learning this new dimension of the hobby.

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