What you’re seeing is the back side. “1” is where I’ll have the dust separator, “2” is the back panel that makes an open exit pathway to outside, “3” is the shop vac, “4” is the Shapeoko 3, and “5” is the soundproofing foam. The idea is to have soundproofing foam on every empty surface on the inside, which means the sides and ceiling for the Shapeoko 3 and shop vac. I also intend to have foam attached on the wood surfaces of the exit path, to muffle the sound from that opening. Both the front and back will have doors with more foam attached.
For the enclosure, I plan to use plywood. What do you guys recommend for soundproofing foam? I see a lot of polyurethane foam products, but I found that is useful for sound absorbing, but not soundproofing. Not sure if that makes a difference? I would like to have a soundproof window as well, any material recommendations?
The reason for this is because I live in an apartment complex and it’s quiet here. I like the quiet, but I would very much like to use my Shapeoko 3 as well. (Couldn’t find a place with a garage unit I can use unfortunately)
I recommend not using “soundproofing foam”. This is a common concept people get tripped up on. When talking about soundproofing, there are 2 distinct use cases.
First one would be keeping sound from escaping a confined space. Like a sound proof room. This is probably what you’re after. It is typically accomplished by walls made of very thick and dense materials. In more expensive setups, there’s an air gap isolating inner and outer shells of dense material to prevent vibrations traveling between them. For a shop project, one of the best bang for your buck and space will be the thickest MDF you can get away with.
Second use case is to prevent sound from bouncing around inside a confined space. This would be like in a recording studio. They put foam on the walls. The foam has nothing to do with keeping the sound from traveling through the walls. Its purpose is to keep sound from bouncing off the walls and back into their microphones.
For an enclosure like you’re wanting, you will get significantly better sound containment with MDF, brick, or concrete than you will with the same thickness of foam or rubber. About the only place it makes sense to use foam is if you have some sort of an exhaust port, like an enclosure for a generator. You would need holes for air flow in the enclosure for the generator to work. A set of baffles with foam would help keep the sound from finding its way out through the openings.
I did a lot of research and basically fell into a rabbit hole of the differences between sound absorbing and sound proofing. I found other alternatives into absorbing the sound. This is a design I have so far (the 2x4s and the columns on the corners are just a frame):
I still have to design the top and bottom soundproofing, but the sides are in place. I was thinking of placing the sound absorbing material on one side of the MDF panel (which will be 1/4" thick) and on the top and bottom sides of it (numbered 2), like below (1 refers to the framing column):
And doing something similar for the front and back doors.
That soundproofing you linked to for laminate floors is not meant to keep loud sounds from escaping through it.
That stuff is meant to go between your wood sub-floor and the floating laminate floor you install over it. Without that, the 1/4" laminate floor sitting directly on the sub-floor reverberates. When you walk around with your fancy dress shoes or in high heels, the sounds echoes. The sound dampening underlayment helps keep the laminate flooring from turning your foot steps into noise and it helps the laminate floor not vibrate so much when there is a sound in the room. So any noise there is in the room wont echo as much.
Like back to my original example, that stuff is more like the foam they use on recording studio walls. It is to keep sounds from bouncing around inside a space. It does little to keep sound energy from penetrating it and being heard on the other side of the wall.
Weatherstripping can be used to seal the door if you overlap your door over your frame. I cut a 1/8” deep groove to accept the weatherstrip and allow it to squish without squishing completely. I used double hung window sash locks to keep the doors pressed in on the weatherstrip. Will probably switch for wooden turn it’s on at some point but they work for now. Seals doors well.
I had success with sandwiching some of that underlayment felt in between layers of plywood. It dampens the sound quite a bit. Not soundproof on its own, but it definitely helps by deadening noise that might come from the vibrations of the box itself.
Ooo, thank you! In that case, I’ll apply some on the border of the door that’ll touch the frame when closed. But also, I’ll sandwich the weather-strip between the MDF panels of the enclosure and the frame itself before screwing the MDF in place. That should take care of any small gaps between the frame and panels. I’ll also use green glue to plug the inner corners as well, for extra soundproofing.
Is there a particular weather-strip you use? Or just any generic one will do?
I used a weatherstrip from frost king that I got at Home Depot. The cutaway profile of the weatherstrip looks like a D and it self-sticks. Is it the best? No idea, but it was available, and it was able to compress from about 5/16” down to about 1/8” and still provide some resistance. 1/8” was the depth of my groove, so it had about 3/16” of compression to push against the door and fill any gap between the door and the frame.
I tried other types, like a flat grey weatherstrip that compressed from about 1/4” down to 1/8, but it was very happy to maintain the compressed size and wouldn’t maintain pressure against the door. Whatever the material of this one was, it didn’t “spring back” to it’s original size very quickly, so i didn’t like how it worked.
Not sure if this description is helpful, but that was my process. Trial and error and you’ll find something that works.
