Soundproofing Ideas

[wojocad]

I've been working with a ShopBot owner, so I've heard his installation... pretty loud with the vacuum system running! Fortunately for him, he has a lot of property in the middle of nowhere. I'm considering buying a ShopBot and setting it up in a flat-roofed, one-car garage in a residential neighborhood. Naturally, I'm worried about noise. Does ShopBot publish any literature regarding decibel levels, frequencies, sound control, etc...?


Soundproofing solutions I'm considering for the walls include...

1.filling in the garage door with an insulated wall panel and a man door
2.filling in all garage windows with insulated wall panels
3.adding batt insulation between the exposed wall studs
4.adding 1/2" plywood sheathing to the interior of the exposed wall studs
5.using USG resilient acoustical clips to hang drywall to the face of the plywood
6.I'm also thinking about enclosing the vacuum system in an insulated plywood box under a countertop or possibly attached high up an a wall.

Soundproofing solutions I'm considering for the roof include...

1.adding batt insulation between the exposed rafters
2.adding plywood or drywall to the underside of the rafters

If anyone has additional ideas or actual experience with soundproofing issues, I'd be interested in hearing about it. Thanks!

[Brady Watson]

I've had great results with 2X6 stick walls & R30 insulation + 5/8" rock for the the walls. The ceiling has R30 in it & you can't hear anything but a whisper outside of the shop when cutting the 'loudest' of materials. The ShopBot is only as loud as the router you are going to use with it. Imagine running a hand router. That's your gauge.

As far as the vacuum pump, that's a whole other thing. Large roots-style vacuum pumps are very loud (usually 90-95 dba) and are ideally enclosed in a mechanical room inside or a lean-to type closet outside of the shop. For the majority of applications that I have seen out there, 4 Fein Turbo III industrial shop vacs are more than adequate & only run about 60 dba or less, with 7" HG & a total of 600+ CFM. You don't need a monster vacuum pump to have a good efficient system.

-B

[fleinbach]

world soFirst, I might say, you may not need to go to such extremes measures. My shop is also located in my garage in a residential neighborhood and sometimes I would have three things running at once. These would include the shopbot, my 5 hp grizzly vacuum system and my circular saw, 3 hp planer or bandsaw. It does not disturbe my neighbors, including the closest one whose bedroom walls are literally 13 foot from my garage wall. The walls are made of half-inch plywood with vinyl siding on the outside. I have walked around the outside of my garage while all those tools were running. And they are barely detectable once I am 50 foot from the building.

After saying all that just last weekI added one more piece of equipment, which is the 7 1/2 horsepower roots blower from shopbot . So far I have run the shopbot my vacuum and roots blower and walked around again outside to see how loud it was. The roots blower has increased the volume to the point where it sounds like a muffled lawnmower running within 50 foot of the building. Sometime this weekend, I will stop in and see my neighbor to see whether it can be heard in his house. In any case, I believe I will also be working on some soundproofing.

I have used the USG resilient acoustical clips in my theater rooms for sound control and they work very well. 5/8 drywall, also works far better than half inch for sound control. Half-inch drywall is far better at sound reduction than half-inch plywood.

What I intend to do is inclose the roots blower and my vacuum system together. That way it will take far less material to control the sound.

Edit

While I was writing this Brady made a post and I will say his comment is very accurate about the Fein turbo vacuums. I ran one before I purchased the roots blower, and it does a very good job. In fact, I intend on switching occasionally between the 2 of them since quite a few of my jobs work fine using the Fein Vacuum

[normand]

Make 2 wall of 2x3 and leave a space between them to avoid acoustic bridging. you can also put your vacumm pump in a pit so you only have to insulate the trapp.

[davidp]

We put a simple truck exhaust muffler on the exhaust of our 7.5 kw vaccum pump and vented the exhaust directly out of the building, it is barely audible outside and we can walk comfortably around inside without earmuffs inside. In fact it is much quieter now than a shopvac.

[fleinbach]

David,

I have been considering using an old muffler from a car and was going to ask that very question. I know what a car sounds like when you take a muffler off and it is much louder than a vacuum pump. What type of truck muffler did you use? Or should I ask how large a truck it came off of.

[steve4460]

Hi Guys
A while back I worked on a movie theater and the sheetrock crew put 2 layers of 5/8 sheetrock on just the regular R 13 insulation When I asked the guy doing it he sayed that the sheetrock insulates better for sound becouse it is solid unlike insulation with airpockets . They put the first layer horizontal and the second vertical and only taped the last layer of it .
Just my two cents

Bot on

[davidp]

Frank

I picked one up at the wreckers, a faily large one, just be sure to vent the exhaust to outside particuarly for the first few weeks as the exhaust deposits from the truck are not nice, but the beauty is that the sound is minimal so your neighbours will not complain.

[wojocad]

Stephan, that 2 layers of sheet rock idea rings a bell for me too. I remember talking to an acoustical consultant once (about wall types for a theatre job), and he said you want MASS to stop sound. Thanks for reminding me.

[pfulghum]

http://www.soundproofing.org
http://www.acousticalsurfaces.com/soundproofing_tips/soundproofing_tips.htm


Basically....

- Isolate the exterior and interior walls with staggered studs or resiliant channel.
- Use metal studs (if possible)
- Use 24" center (if possible).
- Add mass for absorbtion (fiberglass/cellulose in the wall cavities and 2+layers of drywall)

CHeck out the website for all kinds of goodies.

I have spent a small fortune building a shop in a residential area, I will post pictures and ideas soon...

-- pat

[beacon14]

Outer walls: Wood 2x4 (or 2x6) structural walls on 16" centers.
Drywall the ceiling first with 5/8" drywall, tight to the outer walls.
Inner walls: Metal studs on 24" centers - isolate from the ceiling with 1/2" rubber pads. Leave 1" space between outer and inner walls.
Insulation: "Blow-in Blanket" blown fiberglass, completely fills the 8" thick wall cavity.
Drywall: 5/8" drywall hung on resilient channel. Leave 1/4" gap at ceiling and floor, fill gap with acoustical sealant.
Exterior: 1/2" OSB sheathing, felt, furring strips of 1/2" OSB, then siding.

My shop is built this way and you can literally hold your ear up to the wall with my loudest equipment running and not hear anything but the birds in the back yard. I basically combined every method I could find in my research that did not involve buying expensive specialty materials, and it worked.

[billp]

In a prior career I owned a business that offered rehearsal and recording facilities for musicians. I had seven studios adjacent to one another, and I spent YEARS trying to come up with ways to modify the transfer of sound from one room to another. (Of course some of these bands took more pride in their volume than their music, so the challenge wasn't easy....).
I too thought that "mass" would solve all of my problems so I built walls of cement cinder block, and then completely filled all the cavities with sand.....I then left a one foot air space and built the NEXT wall in the same way.....In spite of all my efforts there was still a significant amount of "sound bleed" from room to room. SO I brought in an acoustical engineer (I know, I know, I should have had him there BEFORE I moved all that cement/sand....) and he told me that the culprit was the rebar in the floors and ceilings of my building which were acting almost as "tuning forks" and allowing the sound/vibration to transfer from one room to the next. His solution was what many of the top recording studios in the world have done; they "floated" the entire room on cables so that there was NO tranferral from the outside world into the recording area, and vice versa...
After pricing out that option (exhorbitant...) I wound up adding one more inner wall lined with sound absorbent materials, and while it did not totally solve the bleeding, it DID change the frequencies which were transmitted.
Lower frequencies are the hardest to stop (think of amplified bass drums and 1000 watt amplifiers for the bass/organ players...OR roots vacuum blowers, etc.), but middle and higher frequencies were manageable.
To further control things we ran localized sound "baffles" which were placed as close to specific sound sources as we could, and that kept some of those frequencies from reaching the walls.
It is highly unlikely that most people will be able to modify their shops to be "audibly invisible" but if they can identify the major culprits (Radio Shack sells a cheap DB meter to measure your sound output) it MAY be possible to limit the sound right at the source. And of course there is always the individual situation to keep in mind; if your shop is very close to another building you'll have a lot more work to do than those who are fortunate enough to have some separation from their neighbors....

[Brady Watson]

The most troublesome places in my shop seemed to be ceilings/roof and glass windows. If you can insulate these, you can knock out a large portion of the noise transfer to outside of the shop.

-B

[bcammack]

We built a recording studio inside an industrial building in Irvine, California about 25 years ago. We isolated the slab of the "building within a building" to help eliminate noise infiltration.

Make some masonite panels about 1x2 feet, covered with fiberglass batting (insulation) and hang them from the long edge from the ceiling. Do a pattern of three or four parallel separated by 12" then do another set at a right angle to the first. The sound waves will go up and "get lost" in the absorptive material. That's how we killed "standing wave" issues in recording studios.

[pfulghum]

Here are my windows...

http://www.milgard.com/_doc/products/shared/quietline-hs-brochure.pdf

I bought the top of the line STC 47 windows. a "5040" slider was just about $600. More than 2x the cost of normal windows.

Multiple by 5 and say OUCH.

-- pat

by the way the weight of the window was significant.

[jeffreymcgrew]

A common way to think about blocking sound is:

First, stop any air transmission. Seal the space well. Mass and/or isolation won't mean much if there is still any direct pathway for air to move between where you want it to be quiet and where you're going to be loud.

Second, isolate the space as much as you can. Double layers of rock, air gaps, rock on 1" z-channels, and if you've got the money floating floors and more. You want it such that there isn't a direct path of vibration between the spaces.

Then, third, add mass where you can. Adding mass doesn't help that much if you haven't done one and two to a reasonable level. But ti does help the sound getting out.

Also, we've found that our dust collector is by far the loudest thing in our shop. You might want to plan to put that in a closet or something. The 'bot itself isn't that loud...

[routerclouter]

It seems the cheapest (and maybe the easiest?) way to block noise would be to block the worst sound at the source. Can one build a container for the vacuum system? How should one attach it to the wall? Has anyone tried to block noise from the router or spindle?
Thanks for all the good notes you guys post.

[propellers]

Swapping out old PRT for a 4G board this weekend. There are two blue connectors for input/output on the old board and four on the 4G board. Do I just plug the blue connectors onto the 4G board paying attention to the 12v output connector or is there a sequence I should follow.

Is there other set ups involved or do I just hookup and run with PRT48 setting?

Looked on the web site but saw nothing for the 4G connection guide.

[Brady Watson]

Lonnie,
Pull entire input block off of PRT board. Remove input block on 4G board. Plug old PRT connector right into 4G board. Everything should work just as before. If you are using outputs (eg external relays etc) you will want to wire them to the 4G board spearately. In most cases, you will not have to do this.

You will want to install the USB/Serial converter software BEFORE you plug it into the computer. You will need to download v3.4.30 and choose 4G from the configuration list, AFTER you have loaded the firmware into the 4G board. If you already chose a configuration, just type in UR into SB3 and redo the config, confirming that you want to delete the current config at each prompt. Check your unit values. They will be roughly 1833 XY and 2291 Z. These are for .5° step 3.6:1 motors. If you have a 7.2:1 Z motor (0.25° step label on motor), then exactly double the Z UV.

If you find that the software tells you that input 4/E-stop switch is on when it is not depressed, you will need to go to VN and change the setting for the e-stop from normally closed to normally open.

Hope that helps...

-B