Introduction: Silence Your Laser Cutter!

About: The IDEAWORKS Innovation Suite is part of the Library and Academic Technology department at Washington College in Chestertown, MD.

Have you bought a laser for your home or workspace but aren't a fan of all the noise? This instructable will help you regain a little peace and quiet and actually improve the laser cutter's performance!

Step 1: Goals of the Project & Game Plan

There are two main goals with this project:

  1. Make the laser quieter
  2. Make the laser less likely to vent into the house

The air compressor and the squirrel cage exhaust fan are both a bit loud. I want them quiet enough for other people to be using the room without sound bombardment. Another problem I have experienced in previous laser cutter installations is exhaust smoke leaking into the workspace.

Looking at the illustration, you can see a typical placement of the exhaust fan - somewhere between the laser and an outlet through a wall vent or window. The problem I've experienced previously occurred when then hose between the exhaust fan and wall vent leaks smoke into the room. The exhaust hose is under suction between the laser and the fan, so any leaks will only allow a little room air to be sucked out. But after the exhaust fan's outlet, the hose is under pressure. Any bad seals will leak air into the workspace. In my first laser cutter installation, I found the low-quality flexible exhaust hose developed large leaks when an object must have rolled off the back of the work surface and fallen onto the hose!

My plan is to move the exhaust vent and air compressor outside the house (in a waterproof deck box) so the noise is removed, making the entire run of the vent hose within the house under suction. While I'm at it, I'm going to run the exhaust through an inline carbon filter to reduce the smoke smell in the yard.

Step 2: Gather Your Supplies

Your installation may vary, but here is what I used:

  • (1) 72-gallon Suncast deck box. I chose this model because it had decent reviews and was large enough to hold everything (and was a reasonable price). Make sure you get something that is UV stable or it will fall apart from exposure to the sun before you know it.
  • (4) 6" hose clamps - You'd only need 2 if you just want to locate the exhaust fan outside. In my case I needed 2 additional hose clamps to connect the inline charcoal filter with a short piece of flexible hose within the deck box.
  • (1) 20' section of air/water supply line. I choose a size that would fit over top of 4mm ID (6mm OD) air line my laser came with. If I had used a coupler that needed to go inside the 4mm hose, it would restrict the air flow. So I decided to go slightly larger than the 6mm OD.
  • (2) Small hose clamps to connect the new air line over the old.
  • (2) Power extension cords. My Thunderlaser Nova 35 has a power relay with outlets on the rear of the laser, turning on the exhaust and air assist pump when the laser job is started. I needed to get the above pictured extension cords rather than a typical extension cord to make these run outside in the deck box.
  • (1) Rigid insulation (I bought a 4'x8' sheet of 1.5" thick, but I have a little left over)
  • (1) 90-degree aluminum elbow (6" diameter)
  • (1) Aluminum duct connector (6" diameter)
  • (1) Roll of aluminum adhesive duct tape - similar to the above pictured, but I used Nashua brand (standard duct tape would also work)
  • (1) Vent cover with bird guard
  • Zip ties
  • Paint (outdoor)
  • Scrap piece of 3/4" plywood
  • Scrap piece of cardboard

Step 3: Swapping a Window for a Panel With a Vent Pass-through

In my basement, I was able to open the tilt in hopper style window and remove it from the frame. My first thought was to just remove the glass from the frame or get a replacement window that I could break the glass out of, then use the well-sealing removable window frame to mount my vent. The Home Depot window guy said although my basement windows are only 10 years old, you can't get a replacement window, and I'd have to get an entire window and frame. He strongly recommended against breaking my existing window unless I was prepared to completely replace it down the road.

My method instead was to cut some 1.5" thick rigid insulation the size of the window and seal it in place with some of the aluminum tape. Since this is my basement I didn't need the finish to be beautiful, so the taped edges are visible. If you wanted to dress it up, use the method I discuss later with the outside plywood panel, but also on the inside.

Next hold the 6" vent connector up where you want it to be and trace the outline on the foam with a marker. I used a long bladed utility knife to cut through the foam and fit the connector in through the panel. You could use caulk to seal the vent connector at this point, but I found the aluminum tape worked well.

I used cardboard to make a template for a plywood outer layer, which would provide a little security and also deaden outdoor sound. The cardboard made it easier to get the hole positioned and the size determined before transferring the outline of the template to the plywood. After cutting the wood and checking fit, I sprayed a couple coats of white semi-gloss indoor/outdoor paint to help protect the plywood, even though it is not in a location that would receive direct wet weather.

In the photo, you can also see the power extensions and the air tube, which I'll talk about next.

Step 4: Extend Your Power and Air Outside

Before I closed up the exterior with the plywood, I made a cutout in the foam large enough to fit the ends of the power extension cables through. I ran them from the rear of the laser cutter where they have designated outlets, each controlled by a power relay. I also adapted the 4mm ID air tube to the larger diameter flexible plastic water/air tube I purchased. I used a small hose clamp on either end to be sure it wouldn't work loose. This process replaced the original 4 feet of 4mm ID tube (which connected to a larger hose fitted to the air compressor) with about 16 foot of tube that carried a larger ID all the way from the compressor until about 4 inches from the laser where it attached to a short piece of the original 4mm ID tube. Although I added several feet of air line, I think my airflow is either the same or slightly better having removed about 3.5ft of the more restrictive 4mm ID tube.

To make the installation cleaner, I zip tied the power cords and air line together every few inches from the back of the laser to the exterior location where I set up the deck box.

Step 5: Determine the Placement for the Items in the Deck Box

I started out planning to align the exhaust exiting the fan directly to the right, as shown in the first image, but I realized the air would need to enter the deck box from the back or front side, which I didn't like. Instead, I spun the fan 45 degrees and used a 45 degree elbow to route the exhaust into the side of the box, but still allowing the fan's exit to connect to the inline carbon filter.

When you are trying to determine your positions on the plywood floor, place everything in the box where you think it would fit best, then slide a marker inside to record the base positions for each part. It'll assure your components align properly when you bolt everything down to the plywood and then drop it all in place at once.

I mounted the air compressor under the motor side of the squirrel fan because there is some air that blows out when it is running to help keep it cool. This will also help cool the air compressor in the heat of the summer, and warm up the inside of the box a bit in the cold of winter.

Step 6: Adding Sound Insulation, the Inline Filter, and an Exhaust Vent

Using two 6" hose clamps and a short piece of flexible duct, I connected the exit of the squirrel fan to the inline charcoal filter. I cut some leftover rigid insulation to deaden sound around the fan and air pump. This insulation was held in place with more of the aluminum tape. Since the exhaust coming out of the inline filter dumps into the deck box, I just added a vent to the side with an integrated screen to keep out birds or squirrels. I can't imagine they'd like it in there much anyway! The lid doesn't fit air tight, so it vents out around the edges of the lid as well as the side vent. It does shed water away and doesn't seem to let any in from the top, but since the deck box has seams on the sides and bottom, it wouldn't hold water anyway. There is a place to put a lock on the box, but since the deck box is plastic, this wouldn't be very secure if you were really worried about keeping people out. It will keep the kids from messing with it though.

Step 7: The Results! What Next?

With the exhaust and air compressor sound now removed from the workspace, the only significant sound you hear is the air rushing into the laser (not very loud), and the water chiller (intermittent sound). This setup is so quiet you can focus on the sounds of the laser's motors and the actual etching/cutting sounds. I think that could be an asset because if you have any strange sounds coming from a stepper or servo motor, or maybe from a bearing inside, you'll be able to hear it before it may become a problem.

Although this does make for a comfortable indoor work environment, I do have plans to move the CW-5200 chiller into a closet adjacent to the laser. I'm just waiting for those silicone water hoses to arrive in the mail!

One last thought...from inside the house, you can hear the compressor and exhaust fan faintly through the plywood and insulation. You could do a better job locating the box or increasing insulation more to make it inaudible, but I think it's important to be able to hear it a little. If there's a bearing that goes bad, or if you don't hear the fan spin up at all, you'll want to be able to pick up these sounds to take the appropriate actions.

Please comment below if you have feedback! How would you improve this? What else would you do to make the laser cutting environment as good as possible for a home business? Thanks for reading!