DC Closet questions

[lkazista]

OK mates, so I picked up a used 220V Grizzly 3HP DC a few months ago, it is one of those beasts with 4 bags. It is WAY TOO MUCH DC for me and my tiny shop, but it was only $100 so I had to go for it.

Anyway, to my question; My shop is only 15 x 25, and is in the basement of my house just below the family room, that DC is gonna sound like a jet taking off. So I plan on building a 'closet' to put it in. It will be around 5' by 6', it will also house my circuit breaker panel and the central vac for my house. I want to soundproof the room and ceiling as much as possible.

Do I need a vent to prevent negative airflow to/from the DC? Or can the room get sealed nice and tight?

Secondly, any good tips on how to soundproof effectivly?

Thanks in advance,

Lee

[LCHIEN]

you cannot seal the room tight.
If its sucking air from the duct in the main room then the exhaust throiugh the bags has to find a way back to the main room or it will introduce a great deal of restriction.

if you want to sound proof it but allow air flow you will need baffles. But they tend to eat space.

You should fire it up, it might not be as loud as you think.

[Jeffrey Schronce]

I wouldn't put a DC unit in an enclosed areas with my breaker panel either.

Agree, fire it up. YOu may find that the 3hp motor is not as loud as you think. It is more about the design of the frame, impeller, etc when it comes to noise in my experience. I just went from a 1.5 HP dual drum sander to a 5 hp dual drum sander and the bigger one is quiter.

[LCHIEN]

DCs tend to have a low freq rumble, not a high pitched vacuum squeal.
It'll be much more difficukt to isolate...
But its not as objectionable as a vac.

[lkazista]

OK - point taken on the DC, but what about trying to 'absorb' as much shop sound as possible before it gets to the family room that is directly above?

I have used 1/2 inch homesote in the past, and I have NEVER been impressed with the quality, and at $25 per sheet, I feel that I should be REALLY impressed.

The family is already carpeted with extra thick pad and that certainly helps with the sounds of the shop, but I would love to make it even better, so that I dont have to stop working when the kids go to bed.

Any ideas or suggestions? Thanks for all of the advice thus far.

Lee

[ironhat]

I expect that you will get more valuable info from Loring with his analytical mind and engineers eye but I'll chuck in my layman's idea. There are special stand-off for mounting drywall to studs in order to achieve a more sound proof wall. The standoffs are to help to prevent the studs from transmitting sound to the other side so it stands to reason that you could apply the same tech to the ceiling. But hey, in a pinch you could line the cabinet with some shag carpet - LOL!!

[LCHIEN]

in order to keep sound from transmitting you have to decouple the two places. If the primary transmission is through the living room floor then you need to decouple the DC closet ceiling from the floor above with isolation material, and lead lined foam between the walls or ceiling/floor. The ceiling rafter should not be hard fixed to the floor joists above, but soft coupled - the lower the freq the softer the coupling needs to be.

The sound may also be transmitted to the building structure. You need to keep floor vibrations from getting into the supports that support the house above. The easiest way: decouple the DC from the floor.

Finally the noise may be airborne, low frequency is very non-directional, it will go around corners and up stairways. You need to have an extremely stiff, heavy door or two, with weatherstripping, solidly fastened to the house frame between the basement and the upstairs.

That may get you started.

[TheRic]

OK mates, so I picked up a used 220V Grizzly 3HP DC a few months ago, it is one of those beasts with 4 bags. It is WAY TOO MUCH DC for me and my tiny shop, but it was only $100 so I had to go for it. .....

Nice Stealth gloat!!! And a You Suck!!!!

I wouldn't put a DC unit in an enclosed areas with my breaker panel either.....

I agree with this!!

[Alex Franke]

No kidding, man. How the heck did you score that for only a hundred bucks?!? I should be so lucky.

Here's a novel idea. If you exhaust to the outside and seal all the doors and windows, you'll end up in a vacuum. There goes your sound problem.

I just can't get over the fact that you got that DC for $100.

Don't know if this is a solution (because I haven't found my $100 DC yet), but have you looked into acoustic tiling before? I've used it in the past for studio voice over booths, and it works pretty well...

[TheRic]

Might want to look into what the bags are rated at!! Being in such a closed environment, that thing might be cycling more into the air than if you didn't have a DC at all.

Even if you have to get better bags / canisters you are probably still ahead of what the original price for something 1/2 that is!!

When you are planning the closet for the DC remember you have to be able to empty the thing out, and give yourself room to trouble shoot it.

Not sure you want to put the Central Vac in the same room as the DC. I just seem to see problems. Could you pump dust into the Central Vac, in other worlds send wood dust thru the whole house?!! No clue on how a central vac works, just thinking and typing.

[LCHIEN]

...
Not sure you want to put the Central Vac in the same room as the DC. I just seem to see problems. Could you pump dust into the Central Vac, in other worlds send wood dust thru the whole house?!! No clue on how a central vac works, just thinking and typing.

Good catch on the central vac, the vac will be sucking air from the house.
The make up air, if the house is tight and the shop doors to outside are closed and the basement stair open to the house, will be to push basement air up the stairs to the house. If the DC is not working perfectly then the dusty shop air will end up in the house.

[Mogo]

HI folks, I have been away awhile and I realize this post is dated but I had a similar problem for different reasons.

I did not want the DC system inside my shop for space reasons, but I also live in an area where it gets cold. Putting the whole unit outside would only result in sucking all the hot air out of my shop in a matter of minutes. My solution was to have the cyclone outside but the return air inside.

I build a 30X30 enclosure on the outside of the shop for the cyclone and sealed and insulated it with EndraGold (left over from a soundproofing project) to keep the temp in the enclosure close to the shop temp so there would be no issues with condensation.

As for the soundproofing see this thread (The original post on soundproofing) http://www.bt3central.com/showthread.php?t=24447

[chopnhack]

With regard to the low frequency noise, you may want to try rubber to isolate the unit from transmitting throught the floor and walls. Maybe a thick rubber mat for the DC to sit on.

[smorris]

For soundproofing I have used this material, not real cheap (is anything marine) but very effective at killing the noise. We use it in engine rooms and the difference is night and day.

http://www.marinefoam.com/engine-sou...esoundproofing

The egg crate foam will do an adequate job but the ultra barrier does a great job due to the load mass under the foam. The load mass is typically a thin layer of lead.