My Sound Dampening Enclosure for almost finished CNC Router

[Nealieboyee]

Looks good. Box in box is a classic solution and with minimum structural connection between them should work well. Note that the surrounding inner box will amplify the sound inside which makes the outer box work harder. The carpet will help with absorption but only at fairly high frequencies. If you can line the ceiling with something thicker and fluffier it will help.

Services in and out are best done with long trunking lined with absorption, so don’t just go straight through each panel but start at the top (say) of the inner and bend 90 deg down to run down the void, with a rubber coupling in the middle, then bend 90 and go out of the outer panels. So the upper trunking is mounted to the inner panel and the lower trunking is mounted to the outer panel. You can get rectangular trunking which might fit depending on the gap size.

Good work

Thanks very much for your input. Loved the new video of part one of the pedal car build. Very nice. I wish I could be as neat, clean, and precise as you are. Trunking might be a problem as the gap between inner and outer boxes is only 10mm. But I'm working on baffle boxes to run air and cables in and out.

I think the idea of sound proofing is good, but I also think that the table is not going to be strong and rigid enough for a CNC and that the rubber wheels will make the whole machine too shaky. My CNC is made in a similar way but out of 45x90 aluminium extrusions and originally I also had similar wheels, but after some use I realized that the shake is just too violent when the CNC was in use and that it also affected maximum speed and accuracy, so I changed the solution. The table is now lowered onto the floor, and the wheels are only used when I want to move it around, which is not happening that often. Also, the noise level actually dropped after the change, even though the aluminium extrusion feet is not touching the floor, resting directly on some wooden blocks between the floor and the machine feet. My advice it that you think about this before it is too late, so you don't have to make too many changes later.

Thanks man. I removed all four castors and the table/bench now sits on two planks on the floor. I had to use a car jack to lift it and unbolt the castors haha. Was scary.

First sound test completed. This is with a wood router placed inside the box and the cable simply hanging out the bottom of the door ( squished by the latches). Router is at max rpm. The front panel/door has a single polycarb window 4mm thick on the inside. I will be putting one outside too. I did a small test with my phone playing music inside the box, and the sound leakage was definitely coming mostly through the polycarb, so with a second sheet in place, I expect the sound level to drop further. Listen for the drop in sound level once the third clip is latched.

Honestly, I can't believe how quiet it is. My hand saw makes more noise on each stroke than this. I can still hear ambient noise while this is running. I suppose the true test will be when it starts cutting material like aluminium.