Thread: Powerful shed ventilation for cleaning

I'm sure others will use words like "dumb" to (appropriately) describe this idea!

I don't use a blower, no matter how tempted I am because I suffer badly if I get the dusty stuff into my system, and I get the shivers watching this bloke working without a mask. However, my workplace is connected to living areas of the house and I'm more about keeping the dust from entering those parts.

So, I have a ducted system to my gear, with the machinery located outside, a ceiling mounted air filter AND TWO 12" hydroponics fans like these:

They are noisy enough to be intrusive, need to be left on for a couple of hours to stop dust settling, and are great for removing fumes and most recently the smoke from my old ShopVac. I can and do leave the doors to the house (a hallway and a shared bathroom) and the negative pressure created by them is enough to absolutely keep airborne dust intrusion from the house.

They are not an end in themselves, and I do go round from time to time (annually-ish) and wipe all horizontal surfaces with a damp cloth. I'd do them again in a heartbeat, but they are just one small part of the whole setup.

When you are looking for a fan, make sure to check the volume of air moved - a lot of big fans, particularly those designed for cooling move surprisingly little.

Cheers,

P

These fans are sometimes called barn ventilator fans and are used extensively in intensive animal farming like chicken and pig farming.
Google barn ventilators and you will see lots of them.
Here's one I saw at the Dunsborough mens shed, you can see the brand name on the side of the fan phone number is 0411 228 328
This one is 3HP SP.
DunsMensShed.jpg

Dunsborough MS have a very big shed (~200m^2) and are using this fan as a general ventilator.
BUT
It's VERY noisy and I would not use it or anything like it in my shed.

General ventilation in any workshop is a really good idea but the best thing you can do is to first optimise collect dust at source using a 6" ducting DC system.
ie never let is get as bad as the dude showed in the vid.

Even if you have a good DC many machines and tools may still release some (especially fine) dust so using forced ventilation continually will usually be more than enough to deal with this.
Using a DC system as a general ventilator is usually a poor decision as they are noisy (if you air flow into your DC inlets are not noisy they are not drawing enough air) and costs more to run than small ventilation fans which is usually all that is required if you have even 4" ducted DC system.

At our mens shed we use the large Evap AC as the ventilator - just running the fan only (no cooling) even on low is enough to prevent fine dust levels from building up inside the shed. In my shed I use squirrel cage fans because they are very quiet and draw very little power. Unfortunately these are hard to get hold of so the hydroponics fans as described by BM are a good alternative.

I made a comment on that youtube comments about being dumb had just been shown at a whole new level, I also mentioned Pentz (?) and his wealth of knowledge, the op didnt take to kindly to my comment so he and I had a 'conversation' privetly. I finished up assuring him that he had the same mentality as their president, I think if Id lived closer I might be dead.

Originally Posted by qwertyu

I recently saw this
Dust Extraction on Steroids! - YouTube

He puts a couple of powerful exhaust fans on his shed to clean his shed from dust - .....

My first reaction was that it might make sense in a Melbourne summer, but certainly not in winter - do you really want to pump any lingering warmth out superfast?

Then I saw how he handled his power machinery and switched off. Life is too short to listen to FWs.

Perhaps a better idea would to have the fans blow IN.

Suction out is terrible.... with the 6" pipe on a huge DC the suction was 1/100th of the raw power that the same air being pushed OUT would have been.

Same effect for this dude.... blow in INTO the shop and BLOW it all out the windows.

I used to do something similar in my shop but with compressed air. It blew it all out quick smart. After 9 years I moved and there was very little "hidden" dust even in the most remote nooks.


I will say, the table saw use on this video.... scary.

If the fans move enough air it doesn't matter if they push or pull the air/dust.

An example of successful "pushing" is the HUGE Evap AC fan on the mens shed at work.
It moves so much air it rapidly dilutes the air and fine dust inside with cleaner air from the outside

If only small or small-ish ventilation fans are available then it's usually better to suck the dust out of one side of a shed and make use of diametrical air flows across a shed.
ie fan(s) on one side and inlets on the other to draw fresher/cleaner air in.
This is how we set up all our dust free labs.
Trying to fine push dust out of a room by using a compressor is like herding cats.
Trying to blow dust out of shed in all directions slowly just enable much of the fine dust to mix back into the sides of the air flow that is trying to push it.

It also makes sense to use extractor fans position on a wall - dust productions makes the fine dust and air around it warm so they rise, so locating extraction higher on a wall or roof is desirable.

FWIW, the other day I installed the one of the lower bags onto my dusty 'sub-optimally' and it fell off shortly after hitting the on button. I proceeded to surface plane 6-7 10" wide boards of Vic Ash and then I could see the entire workshop filling up with dust. My dust extractor is housed in a cabinet which is why I didn't notice the bag falling off, and it is vented outside. It usually does a pretty good job, but this was a thick cloud of dust, enough that my camera in my phone could pick up. After talking to myself for a few moments about firetrucks and mothers and truckers etc, I set about installing the bag properly. Turned the dusty on again and disconnected the main inlet duct into the system. So there was only one open pipe right at the source of the dust extractor, and it is a 6" port. It took 4 minutes to clear the dust from the air in my 2 1/2 car garage workshop and pump it outside to my neighbours house somewhere else.

I have an evaporative aircon in my shed, I run that and sometimes use my blower to clean in hard to reach places, the aircon helps push the dust out the doors. My shed is 50 metres from my house and even further to anyone else’s, this might not work as well in suburbia.

oh I refuse to watch the Samurai Carpenter, he just rubs me the wrong way.

Cheers Andrew

Originally Posted by AJ.

I have an evaporative aircon in my shed, I run that and sometimes use my blower to clean in hard to reach places, the aircon helps push the dust out the doors. My shed is 50 metres from my house and even further to anyone else’s, this might not work as well in suburbia.

oh I refuse to watch the Samurai Carpenter, he just rubs me the wrong way.

Cheers Andrew

my eaves are 980mm away from my neighbours, I feel bad if I go out and shake my vac cleaner filter near the power pole.

i think what old mate has shown in the video is a pretty worse case scenario in terms of dust. That being said he really should be striving to capture the dust BEFORE it settles in his shop and not informing others to do so is a pretty big fail in my book.

Originally Posted by woodPixel

Perhaps a better idea would to have the fans blow IN...

Wouldn't blowing winter air into a shed in Melbourne be almost as crazy as doing the same in Canberra???

Originally Posted by Tonyz

I made a comment on that youtube comments about being dumb had just been shown at a whole new level, I also mentioned Pentz (?) and his wealth of knowledge, the op didnt take to kindly to my comment so he and I had a 'conversation' privetly. I finished up assuring him that he had the same mentality as their president, I think if Id lived closer I might be dead.

Tony you have the wrong country that has a dumb Prime Minister, not a president. In the opening to the video the guy said something about being in Princess Auto to get the fans. That's a Canadian company with no US stores. None of which takes away from him being a twit. I also suspect he may be on the west coast where it is relatively mild or he just does his cleanup in the warmer months. It is usually windy enough here that I can open the doors and windows and have close to the same airflow through the shop. The dust on my window screens would verify that. This time of year that ain't going to happen with it being -17ºC this morning without the wind chill. I'm in the capture the dust at source camp.

Have a good New Year
Pete

Originally Posted by QC Inspector

Tony you have the wrong country that has a dumb Prime Minister, not a president.

Must be very annoying for Canadians to have people automatically assume they are American. Not that I have anything against Americans.

If I go with multiple inline hydroponic fans, should I have them in line as series or next to each other at the wall? Will a bell housing on the intake side be beneficial?

I only plan to run these to clean the shed or when doing things where dust extraction is difficult such as a hand held router. It is not my dust extraction solution for those hating on the youtuber...

I have in the past open the blast gates and disconnected the machines and run the dust extractor but it took a long time.

Originally Posted by qwertyu

If I go with multiple inline hydroponic fans, should I have them in line as series or next to each other at the wall?

It's best to locate fans higher up on a wall opposite a major opening/entrance to the shed. (and if possible in the same direction as any prevailing winds) This should create a preferential flow across/though the shed.

Will a bell housing on the intake side be beneficial?

Wont hurt - one on the exit will also help

I only plan to run these to clean the shed or when doing things where dust extraction is difficult such as a hand held router. It is not my dust extraction solution for those hating on the youtuber... I have in the past open the blast gates and disconnected the machines and run the dust extractor but it took a long time.

If possible do your sanding as close as possible to the fans - this means any escaping dust will have less distance to travel to be removed from the shed.