Thread: Extracting interior rooms. Portable ventilator?

Originally Posted by deepblue

Portable Ventilator

Either refered to as industrial fans, or portable ventilators. I'm thinking; unit outside and duct in room; or which ever way your sucking the stale air from the room and dumping it outside , letting a positive pressure bring new air into the room. (I'd tape a tarp round the window/door openning with hole for duct if need be for a better pressure gradient). Could be talking complete bollocks there though, so someone set me straight. Are they worth it?

Steve

I reckon you'll find the 800 cfm is with no ducting attached. Because it's only 1/5th HP as soon as you attach the ducting that flow rate will drop. If you add any pressure gradient at all the flow rate will drop even more. I bet it will also make a fair old racket as well.

Hey Steve,

That unit will only move a heap of air with no velocity, you need to buy a Dust extractor of at least 1hp, I have one and it only just cuts the mustard, I am saving for for a 2hp and some PVC ducting, the cleaner you can get the pipe work the better, minimise the ammount of flexible hose. My other shed had 90mm stormwater pipe as the main trunks and the extractor was 9m from the Lathe port and all the nasties ended up in the Dusty. I am going to change the system in the new shed and have the Lathe port about 2m from the Dusty (Outside) and the drill press about 8m away.
A couple of 10" Extractor fans, in some home made boxes one blowing into the shed and one blowing out would do the same job as the one you featured but half the price, and would do a better job than what you have at the moment.

Good luck

HazzaB

Originally Posted by HazzaB

Hey Steve,

That unit will only move a heap of air with no velocity ....

.....A couple of 10" Extractor fans, in some home made boxes one blowing into the shed and one blowing out would do the same job as the one you featured but half the price, and would do a better job than what you have at the moment.

So basically, air movement with low velocity is merely air turbulance?! I know I'll need some sort of 1HP dust extractor whilst working. I'm just thinking about whole room air exchange (however slow).

Presumably you want the fans as geometrically apart as possible. And ideally, the only passage of air flow in and out of the room through fans. If that is the case. Would it ironically be better to have the twin garage door down. (servere artistic impression used): -



One of these: Industrial Extractor Fan 250mm, 10 inch, 240V, 1300 rpm on eBay (end time 16-Mar-10 09:01:25 GMT)

offer 0.21 cubic metres a second, thats 12.6 /min, 756 cubic metres an hour.
The garage is 56.25 metres cubed in volume. So thats around 13 ACH. air exchanges per hour. But hey all this maths is meaningless when you take into account the fudge factor due to the inefficiency of sealing a room (for equilibrium pressure) due to practicality (you have to be able to come and go!), may well be looking at 20% or less efficiency. maybe actually 2 or 3 decent changes per hour at best. Wonder if its worth it, something has to be better than nothing. *shrug*

Originally Posted by deepblue

Hey folks. I have been doing an awful lot of searching on dust extraction. This place really has openned my eyes to the need for taking such things seriously which I had not been at all if I'm honest. So firstly a confession:

Have to admit using a SCMS, and router without any extraction OR respiratory protection in the garage for the past few nights, whoops. No more though; I've been wearing an asbestos grade P3 half face mask today for entering said contimated area, and will be cutting outside from now on where possible , which to be fair I always do except the past few nights. And placing extracting units (once bought) outside of garage. It really is funny that I only thought mdf and the glues in plywood were the nasties to worrry about and therefore avoided creating any fine dust from plywood, or using mdf at all for that matter. And yet i was happily routing away some pine cabinet door yesterday without any clue. Live and learn! Can't praise this forum and pentz's website enough.

Anyway, to the subject at hand. I have searched this forum, and I can't find much reference to portable ventilator systems. Having read how fine dust can suspend in air for prolonged periods. I'm looking for a solution to maximising the exchange of old contiminated air in the garage with fresh outside air without fitting any permanent extraction fans. Futhermore I haven't found much regarding dust extraction for interior rooms (where for all intents and purposes) woodworking can take place on occassion. So has anybody any experience or thoughts one of these type of machines:

Portable Ventilator

Either refered to as industrial fans, or portable ventilators. I'm thinking; unit outside and duct in room; or which ever way your sucking the stale air from the room and dumping it outside , letting a positive pressure bring new air into the room. (I'd tape a tarp round the window/door openning with hole for duct if need be for a better pressure gradient). Could be talking complete bollocks there though, so someone set me straight. Are they worth it?

Steve

Are you in Kent England? or Australia somewhere
If your in kent England I can understand why you are working with the doors closed ( too cold) lol
Otherwise the SCMS for the occassional use I would not worry about the dust. If you are using it for 8 hrs a day everyday in an enclosed space then dust may be an issue.

If you are using the router a dust mask will suffice and try and work outside as much as possible

I think bill Pentz has alot of relevant stuff to say but I also think because of his lung issues he has to be on the paranoid end of the scale. I think he is over the top for the home user. I dont think we are going to have a explosion of lung cancer due to wood dust in the future. as we havent seen it currently.

Do take care with MDF though

Andrew

Hi Steve,
I use a portable ventilator in my 2 car garage workshop to clear out dust and it works great. I can't find the product on their website catalogue but if you have a look at the home page for Sydney Tools here SYDNEY TOOLS and look at the image across the top of the page- the third item is an orange extractor fan. It's about 30-40cm diameter and comes with a long collapsible/flexible ducting (about 10m or so) that can be run out a window. The ducting can be placed on either side of the fan so you can have air moving either way. The ducting is made from vinyl and contains a number of metal hoops to keep it round.
I originally bought this for a bathroom renovation project where I was generating huge amounts of dust chipping up old tiles and concrete- I went from a room where I couldn't see through the dust in the air while I was using the impact drill to clear air with virtually no dust settling in the room. I now use it in my woodworking shop to circulate air outside to supplement my equipment dust extraction. I just set it up in 1 window and open another window at the far end of the workshop.
From memory the fan cost about $200.