quieter extraction

[sunnybob]

might as well get all my questions in as soon as poss. to enable me to gather stuff for the mark 2 extraction system.

I need to make my SIP 50 litre dust extractor more neighbour friendly. has anyone made any kind of sound proof (or deadening) enclosure for a shop vac?

 

[mikebeetle]

No, but i believe if you pipe the exhausted air to the outside that will help considerably

 

[John15]

If you line your shed with decent insulation then I imagine the sound would be negligible from outside. I get more noise from my bench saw and sander.

John

 

[sunnybob]

No, but i believe if you pipe the exhausted air to the outside that will help considerably

Not so simple. the SIP has a vent all around the top mounted motor I would have to box it in to fit a vent tube.
And the vent tube would point directly at the neighbour I'm trying not to upset.

 

[sunnybob]

If you line your shed with decent insulation then I imagine the sound would be negligible from outside. I get more noise from my bench saw and sander.

John

Again, not easy in my case. My garage has a roller door at each end. Impossible to insulate without losing access.

 

[RogerP]

Not what you want to hear but the simple answer to dust extractor quietness is to get an extractor that has an induction motor and not (like yours) a brush motor.

 

[sunnybob]

Not what you want to hear but the simple answer to dust extractor quietness is to get an extractor that has an induction motor and not (like yours) a brush motor.

nope, not what I want to hear. Looks like I shall have to be a pioneer in the field.

 

[Willy]

I'm recovering from surgery right now and posting from my phone, so I can't easily link to any examples. However a quick Google will find examples of others who have done exactly what you want.

Essentially you build a cabinet to house the vacuum and line it with a dense sound absorbing foam.

You'll need to pay careful attention to venting the exhaust, both to reduce noise and to ensure effective cooling of the motor.

I plan to do exactly this type of build for my workshop when I assemble it...

 

[sunnybob]

I'm recovering from surgery right now and posting from my phone, so I can't easily link to any examples. However a quick Google will find examples of others who have done exactly what you want.

Essentially you build a cabinet to house the vacuum and line it with a dense sound absorbing foam.

You'll need to pay careful attention to venting the exhaust, both to reduce noise and to ensure effective cooling of the motor.

I plan to do exactly this type of build for my workshop when I assemble it...

Thats more like what I want to hear
I have been thinking on the same lines as a large speaker enclosure, with a reflex tunnel. Its the high whine I need to reduce considerably, so all I have to do is slow the air to sub sonic speeds. Any idea if a cyclone adds noise to the extraction? I shall be fitting one. i might have to make the box a lot bigger.

 

[Willy]

When I can get to a computer I'll link to a couple of videos and designs. You ought to be able to reduce the sound pressure level from (what I assume will be) about 90dBA to about 80dBA. That's well over a halving of reduction in SPL.

It's worth reading the science behind sound absorption to allow you to come up with the best design. In short, any single solution is only truly effective for one frequency band and the effect will lessen as you increase or decrease the frequency from there. So to get a good wideband reduction you usually have to employ multiple methods.

I think my design will include some absorption (rigid rock wool insulation most likely) as well as a means of decoupling the vacuum from the box it's in. One idea I have is a box within a box if that makes sense.

 

[Wizard9999]

This old thread resurfaced a few days back, may be worth a look at the link in the second post on the second page of discussion...

outside-enclosure-for-dx5000-now-vented-outside-with-pics-t40846-15.html

Terry.

 

[sunnybob]

When I can get to a computer I'll link to a couple of videos and designs. You ought to be able to reduce the sound pressure level from (what I assume will be) about 90dBA to about 80dBA. That's well over a halving of reduction in SPL.

It's worth reading the science behind sound absorption to allow you to come up with the best design. In short, any single solution is only truly effective for one frequency band and the effect will lessen as you increase or decrease the frequency from there. So to get a good wideband reduction you usually have to employ multiple methods.

I think my design will include some absorption (rigid rock wool insulation most likely) as well as a means of decoupling the vacuum from the box it's in. One idea I have is a box within a box if that makes sense.

I was heavily into hi fi many moons ago, its just a reverse speaker problem really. I found a you tube link that had literally a convoluted set of baffles in a rat run to slow the sound down (what did we do before you tube?)
Nothing will happen for a month now, gotta back to the UK on weds to see the grandkids. I hope the weather is warm enough for me. :roll:

 

[beech1948]

I have one of my DX4000s in a box to reduce sound levels as they are close to a neighbour's boundary.

Box is 12mm ply with a softwood inner frame. Lined with dense sound absorbent foam about 35mm thick. My DX4000 exhausts air from around the top. It has 2 motors so I was concerned about it overheating.

I made a 300mm square external box with 3 baffles for the bottom to act as an air inlet and a 2 baffle version for the top to act as an exhaust and relied on air pressure to create a flow from bottom to top.

Its been like that for about 20 months with no problems to the DC and no overheating. Neigbours say they are OK with sound levels and have no complaints.

I will do the second DX4000 this summer. Current problem is that my Henry shop vac is noisier than the DC by a big margin and I will need to do something about it.

 

[sunnybob]

I have one of my DX4000s in a box to reduce sound levels as they are close to a neighbour's boundary.

Box is 12mm ply with a softwood inner frame. Lined with dense sound absorbent foam about 35mm thick. My DX4000 exhausts air from around the top. It has 2 motors so I was concerned about it overheating.

I made a 300mm square external box with 3 baffles for the bottom to act as an air inlet and a 2 baffle version for the top to act as an exhaust and relied on air pressure to create a flow from bottom to top.

Its been like that for about 20 months with no problems to the DC and no overheating. Neigbours say they are OK with sound levels and have no complaints.

I will do the second DX4000 this summer. Current problem is that my Henry shop vac is noisier than the DC by a big margin and I will need to do something about it.

doesnt the vac motor get cooled by the air its sucking in? I havent had mine apart, but I dont think it has two motors. Seems to my newbie brain that the motor will only overheat if the pipe gets restricted?
If so, the clear pipe will always show the flow levels and do away with overheating.

 

[beech1948]

sunnybob,

here is my DX4000http://www.recordpower.co.uk/product/fine-filter-twin-motor-80-litre-extractor--hplv#.VNj-6PmKVcY. Thast link shows 2 motors and 2 switches.

Yes the exhaust at the top I think creates extra air pressure in the box and air is exhausted from the top baffles. Air to replace this is also drawn up from thebottom baffles.

At least thats my theory and it seems to work OK.

 

[Willy]

I have one of my DX4000s in a box to reduce sound levels as they are close to a neighbour's boundary.

Box is 12mm ply with a softwood inner frame. Lined with dense sound absorbent foam about 35mm thick. My DX4000 exhausts air from around the top. It has 2 motors so I was concerned about it overheating.

I made a 300mm square external box with 3 baffles for the bottom to act as an air inlet and a 2 baffle version for the top to act as an exhaust and relied on air pressure to create a flow from bottom to top.

Its been like that for about 20 months with no problems to the DC and no overheating. Neigbours say they are OK with sound levels and have no complaints.

I will do the second DX4000 this summer. Current problem is that my Henry shop vac is noisier than the DC by a big margin and I will need to do something about it.

doesnt the vac motor get cooled by the air its sucking in? I havent had mine apart, but I dont think it has two motors. Seems to my newbie brain that the motor will only overheat if the pipe gets restricted?
If so, the clear pipe will always show the flow levels and do away with overheating.

My shop vacs are certainly cooled by the air drawn in through the hose.

One thing to note is that each 90 degree bend in your exhaust baffle/channel decreases the airborne noise in the exhaust by either 3 or 6dB (can't remember which). However it will also increase the air resistance that the vacuum pump sees. That will have a negative impact on the efficiency of the suck. So it will be a bit of a balancing act and a compromise between the two.

 

[sunnybob]

I have one of my DX4000s in a box to reduce sound levels as they are close to a neighbour's boundary.

Box is 12mm ply with a softwood inner frame. Lined with dense sound absorbent foam about 35mm thick. My DX4000 exhausts air from around the top. It has 2 motors so I was concerned about it overheating.

I made a 300mm square external box with 3 baffles for the bottom to act as an air inlet and a 2 baffle version for the top to act as an exhaust and relied on air pressure to create a flow from bottom to top.

Its been like that for about 20 months with no problems to the DC and no overheating. Neigbours say they are OK with sound levels and have no complaints.

I will do the second DX4000 this summer. Current problem is that my Henry shop vac is noisier than the DC by a big margin and I will need to do something about it.

doesnt the vac motor get cooled by the air its sucking in? I havent had mine apart, but I dont think it has two motors. Seems to my newbie brain that the motor will only overheat if the pipe gets restricted?
If so, the clear pipe will always show the flow levels and do away with overheating.

My shop vacs are certainly cooled by the air drawn in through the hose.

One thing to note is that each 90 degree bend in your exhaust baffle/channel decreases the airborne noise in the exhaust by either 3 or 6dB (can't remember which). However it will also increase the air resistance that the vacuum pump sees. That will have a negative impact on the efficiency of the suck. So it will be a bit of a balancing act and a compromise between the two.

Plan "A" (always open to much modification) is to have a 3 metre straight run of 63mm clear pipe, with 5 tees to feed the equipment and a floor cleaning hose. A blast gate at each outlet to keep the suction strong on whatever is being used. At the far end the 63 will step down to 55 to fit the cyclone. Then 55 out the cyclone stepping up to 100 at the vacuum body.
I cant understand why everything I buy has a different diameter, what the hell is wrong with having standardised pipe? Come back Mr. Whitworth, all is forgiven!

Once its complete and I find out just how much noise I have to deal with, I will make something for that. I suspect a framework with a large thick blanket will help a lot.
But... I cant box it too tight. I do have to consider heat, the summer here is always high 30s for a few months, and I have had to endure 43 once. :shock: :shock: 8) 8)

 

[Willy]

You could certainly place a digital thermometer probe inside the enclosure to allow you to monitor the temperature.

Now I'm out of hospital it's much easier for me to find some links. Here's a video/article on Finewoodworking: http://www.finewoodworking.com/workshop/video/build-a-simple-box-to-muffle-your-shop-vac.aspx

http://www.startwoodworking.com/post/how-silence-your-shop-vac

A guy that made his own design based on this article:

Part one: https://www.youtube.com/watch?v=NKkbq1fcKz4
Part two: https://www.youtube.com/watch?v=JjqXeAhCp3o
Part three: https://www.youtube.com/watch?v=B8Z7NYBKMTE

He doesn't use any absorption material and just relies on the MDF.

This guy's one is better IMO:

https://www.youtube.com/watch?v=Bd2nhNf9Tp8

And possibly the best design of all, though maybe not the best executed: http://www.instructables.com/id/Dust-Sniper-quiet-extractor-system/?ALLSTEPS

The biggest thing I dislike about most of these is the exhaust design. I plan to directly port my exhaust from the vacuum unit with a pipe through some baffles and then to the outside world. This way I ensure that the majority of the heat is carried away from the vacuum's enclosure. Their designs allow the heat from the exhaust (which on my shop vac is almost all dissipated heat, the cooling really is effective) to stagnate in the enclosure. It does however make good use of the absorptive materials inside the main enclosure.

I think my design may end up being overkill and relatively expensive, though I will predominantly be using stock I already have (and I love this kind of thing). I'd love to build a box-within-a-box where the inside box is lined with foam, then suspended with bungee cord from the outer box (decoupling the two boxes and also absorbing some energy through suspension) and then lining the outer box with rigid rockwool. The box may be large and rather heavy, but the intention is that I only end up hearing the suck of the air going into the pipe

 

[sunnybob]

You could certainly place a digital thermometer probe inside the enclosure to allow you to monitor the temperature.

Now I'm out of hospital it's much easier for me to find some links. Here's a video/article on Finewoodworking: http://www.finewoodworking.com/workshop/video/build-a-simple-box-to-muffle-your-shop-vac.aspx

http://www.startwoodworking.com/post/how-silence-your-shop-vac

A guy that made his own design based on this article:

Part one: https://www.youtube.com/watch?v=NKkbq1fcKz4
Part two: https://www.youtube.com/watch?v=JjqXeAhCp3o
Part three: https://www.youtube.com/watch?v=B8Z7NYBKMTE

He doesn't use any absorption material and just relies on the MDF.

This guy's one is better IMO:

https://www.youtube.com/watch?v=Bd2nhNf9Tp8

And possibly the best design of all, though maybe not the best executed: http://www.instructables.com/id/Dust-Sniper-quiet-extractor-system/?ALLSTEPS

The biggest thing I dislike about most of these is the exhaust design. I plan to directly port my exhaust from the vacuum unit with a pipe through some baffles and then to the outside world. This way I ensure that the majority of the heat is carried away from the vacuum's enclosure. Their designs allow the heat from the exhaust (which on my shop vac is almost all dissipated heat, the cooling really is effective) to stagnate in the enclosure. It does however make good use of the absorptive materials inside the main enclosure.

I think my design may end up being overkill and relatively expensive, though I will predominantly be using stock I already have (and I love this kind of thing). I'd love to build a box-within-a-box where the inside box is lined with foam, then suspended with bungee cord from the outer box (decoupling the two boxes and also absorbing some energy through suspension) and then lining the outer box with rigid rockwool. The box may be large and rather heavy, but the intention is that I only end up hearing the suck of the air going into the pipe

well, thats proved it can be done. i cant vent to outside without serious plumbing work,plus it would point directly at the neighbours patio so I need to keep it "in house".

I'm impatient now to start, but I;m off tomorrow on a 3 week trip back to see family and friends, so it will be well into march before I have anything to report.
thanks for the links, let us know how yours progresses (although I think the spring box inside the box is actually slight overkill :roll: 8) :lol:

 

[sunnybob]

You could certainly place a digital thermometer probe inside the enclosure to allow you to monitor the temperature.

Now I'm out of hospital it's much easier for me to find some links. Here's a video/article on Finewoodworking: http://www.finewoodworking.com/workshop/video/build-a-simple-box-to-muffle-your-shop-vac.aspx

http://www.startwoodworking.com/post/how-silence-your-shop-vac

A guy that made his own design based on this article:

Part one: https://www.youtube.com/watch?v=NKkbq1fcKz4
Part two: https://www.youtube.com/watch?v=JjqXeAhCp3o
Part three: https://www.youtube.com/watch?v=B8Z7NYBKMTE

He doesn't use any absorption material and just relies on the MDF.

This guy's one is better IMO:

https://www.youtube.com/watch?v=Bd2nhNf9Tp8

And possibly the best design of all, though maybe not the best executed: http://www.instructables.com/id/Dust-Sniper-quiet-extractor-system/?ALLSTEPS

The biggest thing I dislike about most of these is the exhaust design. I plan to directly port my exhaust from the vacuum unit with a pipe through some baffles and then to the outside world. This way I ensure that the majority of the heat is carried away from the vacuum's enclosure. Their designs allow the heat from the exhaust (which on my shop vac is almost all dissipated heat, the cooling really is effective) to stagnate in the enclosure. It does however make good use of the absorptive materials inside the main enclosure.

I think my design may end up being overkill and relatively expensive, though I will predominantly be using stock I already have (and I love this kind of thing). I'd love to build a box-within-a-box where the inside box is lined with foam, then suspended with bungee cord from the outer box (decoupling the two boxes and also absorbing some energy through suspension) and then lining the outer box with rigid rockwool. The box may be large and rather heavy, but the intention is that I only end up hearing the suck of the air going into the pipe

well, thats proved it can be done. i cant vent to outside without serious plumbing work,plus it would point directly at the neighbours patio so I need to keep it "in house".

I'm impatient now to start, but I;m off tomorrow on a 3 week trip back to see family and friends, so it will be well into march before I have anything to report.
thanks for the links, let us know how yours progresses (although I think the spring box inside the box is actually slight overkill :roll: 8) :lol:

ok, I couldnt wait 3 weeks, so I just had a quick look at the suction motor.

i was surprised to see it already has foam "deadening" around the motor. Believe me, it doesnt work! this thing is painfully high pitched. only a bit lower than a dentists drill.

under the foam is a lot of room, I can easily lose this foam, and the plastic cover / handle, and reduce the overall height of the box by at least three inches. This will also give more air around the motor top for cooling.