Another router table question: sound deadening

[Paul F Franklin]

Anybody line the inside of the router box area of their table with any sound deadening material? If so, what did you use and did it make much difference?

I've done a few simple things to try minimize direct sound transfer: A solid plywood door with stops all around and foam weatherstripping, a baffle over the makeup air holes, and resting the top on rubberized cork strips to isolate the top from the cabinet a little. But curious if folks have lined the router box with anything.

[Mel Fulks]

I've always just used the spring loaded quiet ear muff stuff.

[Bill Dufour]

I painted the underside of my tablesaw with water based grafting seal. Theory is to soak up vibrations and a little noise reduction.
Bil lD

[Lee Schierer]

I always wear hearing protection when running a router or a sander. That does a pretty good job of noise reduction.

[Jim Becker]

The nature of the device's sound levels and frequencies combined with the fact that the cabinet isn't sealed, allowing for direct sound transmission means that adding any kind of sound deadening is going to provide little dampening. It will not harm anything, but may not be worth the effort. Unfortunately tools that use screaming universal motors pretty much dictate using personal hearing protection and having understanding family members and neighbors.

[Tom Bender]

Hi Paul
Sure, hearing protection is the easy answer but noise control is a good approach too. My wife can sleep thru shop noises in the morning but I still like to minimize it for her and for myself.

Your router needs air so the box needs to accommodate that. A longer baffled path for the air will help.

Low frequency sound is best stopped with mass, but that is not the real problem. High frequency sound is best absorbed in this case and your question is right on track. Lining the box and airway should help. Ceiling tiles should work, either fiberglass or other, but the heavier the better. This should be inexpensive and easy enough to do.

Transmission thru the mounting surface will be more difficult, but you have already done something with that.

[Paul F Franklin]

Thanks all for thoughts and ideas! I absolutely wear hearing protection when doing any machine work, but my thought is that noise control is similar to dust control....controlling it at the source makes everything else easier. Now that my table is done, with no lining of the router box (yet), I can report that it is quieter than I expected. Probably because my old router table just had the bare router hanging below the table with no enclosure at all. The router can be heard above the sound of air rushing into the dust collection points, but subjectively it is not that much louder than the air rush sound level. When I have a little time, I will probably take some sound level measurements and then try lining the router box and see what kind of reduction there is, if any.

[Jim Becker]

What you're experiencing, Paul, is a reduction in "direct transmission" of sound which can lower its apparent volume level. That, combined with having some softer surfaces in the workshop to absorb reflection of high frequencies can help a whole lot. Personal protection is still required, but it will work noticeably better.

[Paul F Franklin]

Thanks Jim. Unfortunately, *I'm* the largest soft surface in the shop;)

[Jim Becker]

Thanks Jim. Unfortunately, *I'm* the largest soft surface in the shop;)

ROFLOL!!!! I resemble that remark!

Seriously, this topic is a major reason why I'm so glad I put in the acoustic ceiling tiles in my shop. "YUGE" difference...you can feel it just walking into the room. I bet even a reasonably small number of panels just stapled up would help many folks with this...'kinda like they do in some restaurants with "open to the roof deck" hard surfaces to reduce some of the noise level.

[Mark Daily]

ROFLOL!!!! I resemble that remark!

Seriously, this topic is a major reason why I'm so glad I put in the acoustic ceiling tiles in my shop. "YUGE" difference...you can feel it just walking into the room. I bet even a reasonably small number of panels just stapled up would help many folks with this...'kinda like they do in some restaurants with "open to the roof deck" hard surfaces to reduce some of the noise level.
Jim- I’d like to hear more about these tiles. Do you have a thread on this?

[Jim Becker]

Jim- I’d like to hear more about these tiles. Do you have a thread on this?

No, I don't believe I have a thread specifically on it, but I started with it about the time I put in my MiniSplit and ordered my CNC machine. My shop ceiling got R30 insulation and then I stapled up "inexpensive" acoustic ceiling tiles rather than putting them in a drop-frame. I wasn't trying to make it look super pretty...I wanted to cover the insulation (required for fire code) and provide a nice reflective surface for my lighting. Both of those goals were accomplished and the "extra" benefit was the tremendous reduction in sound transmission. Honestly, if I turned off the HVAC system, my shop is "dead silent" enough that I believe I could easily record an album out there if I was so inclined. Some of the tiles I sourced from the ReStore and the remainder came from Lowes. You can see the ceiling in this shot from my Ring camera that's in the shop...

https://ub2nha.sn.files.1drv.com/y4muQYmjmqb-K3eYwwnoZ9-rASoZ7J7LbdyMVTkw7NSlXwoMgyKxiDhq9RrH4F_G2aT9puSD5 NV-NLMsZebFeQ6pUsDStY9Q9lVH3-gnloWhvHhe6rSgg1R9SBTt51pTaQwMtBnCooOjoFEZLJYcYghg s3OwDMBsL8kY75yK8-cTXt1BgvMc9CxGCDMY0QpuJGPGad1PbLdZ9oI8wuX6qwFWA?wi dth=701&height=341&cropmode=none

[Andrew Seemann]

I have some acoustic ceiling tile in the enclosure in my table for the router. It helps some, though obviously not everything is absorbed. I also have the ceiling covered with acoustic tile. That helps greatly, as does not having drywall on the walls (I have OSB plus way too much stuff on the walls). It is one of the first things that people who have shops comment on when they first visit mine, that it seems quieter than their shops.

[Andy D Jones]

A two-blade router bit, rotating at 20k rpm, generates a 666 Hz primary frequency (a devilish noise) while cutting. This frequency is reasonably well conducted by wood, which means the entire work piece becomes a sounding board.

Sound-dampening approaches to the area (ceiling, walls, floors) help prevent transmission outside the workshop, and help absorb rather than bounce the noise around inside the shop, but there is no substitute for good in/on/over the ear noise protection.

Andy - Arlington TX

[Andy D Jones]

Also, assuming the shop space is rectangular, with a ceiling parallel to the floor, you need only treat two adjacent walls, and either the floor or ceiling, to suppress repeated reflections inside the shop. Since many shop walls are full of shelves, gear, etc., treating just the ceiling can make a major difference. But this only suppresses repeated reflections, not transmission outside the shop (e.g. to other adjacent areas of the house).

Andy - Arlington TX

[Mark Daily]

No, I don't believe I have a thread specifically on it, but I started with it about the time I put in my MiniSplit and ordered my CNC machine. My shop ceiling got R30 insulation and then I stapled up "inexpensive" acoustic ceiling tiles rather than putting them in a drop-frame. I wasn't trying to make it look super pretty...I wanted to cover the insulation (required for fire code) and provide a nice reflective surface for my lighting. Both of those goals were accomplished and the "extra" benefit was the tremendous reduction in sound transmission. Honestly, if I turned off the HVAC system, my shop is "dead silent" enough that I believe I could easily record an album out there if I was so inclined. Some of the tiles I sourced from the ReStore and the remainder came from Lowes. You can see the ceiling in this shot from my Ring camera that's in the shop...

https://ub2nha.sn.files.1drv.com/y4muQYmjmqb-K3eYwwnoZ9-rASoZ7J7LbdyMVTkw7NSlXwoMgyKxiDhq9RrH4F_G2aT9puSD5 NV-NLMsZebFeQ6pUsDStY9Q9lVH3-gnloWhvHhe6rSgg1R9SBTt51pTaQwMtBnCooOjoFEZLJYcYghg s3OwDMBsL8kY75yK8-cTXt1BgvMc9CxGCDMY0QpuJGPGad1PbLdZ9oI8wuX6qwFWA?wi dth=701&height=341&cropmode=none

Thanks Jim- that’s great information!

[jeff norris 2011]

I always wear hearing protection when running a router or a sander. That does a pretty good job of noise reduction.

Same here. Not sure why I have not yet sprung for Bluetooth hearing protection, as when I have lots of sanding or routing to do I slip in earbuds and listen to a podcast or music.

[Andrew Seemann]

Note that stapling is not a particularly enjoyable way to put the tiles up:) You get rained on by ceiling tile dust which hurts to breathe (and is probably full of silicates or other bad stuff). I stapled the first 5 of my ceiling and then used 1 1/4 screws for the rest.

[Bill Dufour]

I have noticed in the band room and orchestra room they have acoustic tile so on the ceiling and on some of the wall. The wall is glued? on and stops 6" short of the ceiling it comes down several feet but stops well short of the floor. Big patches of wall with no tiles. So they feel any little bit extra helps but no need for total coverage to get some benefit.
Bil lD.

[Jim Becker]

Note that stapling is not a particularly enjoyable way to put the tiles up:) You get rained on by ceiling tile dust which hurts to breathe (and is probably full of silicates or other bad stuff). I stapled the first 5 of my ceiling and then used 1 1/4 screws for the rest.

Totally agree, although I stapled the whole thing. :D Eye and breathing protection mandatory and I also wore a hat.


I have noticed in the band room and orchestra room they have acoustic tile so on the ceiling and on some of the wall. The wall is glued? on and stops 6" short of the ceiling it comes down several feet but stops well short of the floor. Big patches of wall with no tiles. So they feel any little bit extra helps but no need for total coverage to get some benefit.
Bil lD.

You can actually make a room "too dead" relative to sound for most applications. So yes, some "moderation" is a best practice.

[Paul F Franklin]

Hey Jim, Just curious, in your shop photo: what are those two yellow things with the black elephant trunks in the right hand foreground?

[Jim Becker]

Hey Jim, Just curious, in your shop photo: what are those two yellow things with the black elephant trunks in the right hand foreground?

Grip Tight featherboards that I use primarily on the bandsaw. They are the yellow plastic versions. There's a thread in the classifieds (shop cleanout #2) that shows a couple of the original wood ones the manufacturer started with, although I doubt that thread will be there much longer) These have a magnetic base and you position them on the table so that the features and/or rollers contact the material and hold it against the fence.

[George Makra]

Your router spins at a very high speed and creates some very high frequencies you can dampen the noise a bit by putting rubtex (it's a dense neoprene like material that is used for insulation)
Since sound and vibration are linked applying a dense foam to the inside of the router table will dampen the noise a bit. You don't have to seal it up you just want to bounce the sound around in the dense foam.
Think of it as playing a pin ball machine only with noise.