Thread: HELP PLEASE!!! design for dust extraction

Congrats on your assignment. Maybe.

If it were me I wouldn't cast any pipes into the slab. I would however make troughs about a foot deep and two wide to carry the services. Checker plate or suitably thick timber/ply covers keep the floor more or less flat but lift off for easy servicing. Three troughs spaced evenly across the floor should be enough. Connections to the Cyclone can be made across the end of the shop above the floor.

Run 6" or your metric equivalent diameter pipe for collection to the machines. Something else to consider is that wherever you need suction you will need power and perhaps air, so they go in there too. With the access you can clear clogs, modify or add locations when reorganizing the shop or for new machines. Some overhead ducts for saw blade guards etc., are useful and around the perimeter for bench machines.

Pete

I cannot stress how wise QC inspector is. If you bury pipes in the cement you will be forced to use too much flexible hose to allow for machine placement flexibility. The idea of having some troughs for all your services is a great one. If you can I would use 8" or 9" for the main run as this is what you will need if you want something like a Clearvue CVMAX. Have you seen the Corimal Mens Shed site? if not you should it is one of the best I have seen.

It is generally better to have angled joins rather than 90 degree so you might want to consider a V shape pattern into a central main line. Another consideration is blast gates as you must be able to locate these to allow control of each machine. Using a sub-floor based system helps here as normally we recommend placing the gate as close to the main duct as possible which puts them out of reach. This is to stop dust dropping down the duct towards the gate. This is not an issue if the joins go into the top of the main duct.

If you are still able I would consider a small addition to the outside of the shed to house the actual dust extractor to allow for noise reduction and maybe even allow the exhaust to be vented to the outside to save the cost of filters.

I agree with the idea of channel in the concrete but you don't want too many as the the will still be a bit of a nuisance and add significantly to your cost. For a 12x12 shed I would only run two channels evenly spaced across the shed. This creates 3 strips 4m apart allowing 2 m lengths of flexy to cover access to all areas in the middle of the shed. The final 2m on the sides can be covered by ducting running down the sides and back of the shed. In practice what happens is machines will find their way near the floor ducting so you won't need to use 2m long flexy connections for most machines.

I would use 6" ducting in the channels and long the walls and connect these up to 8-9" ducting along one end and take that large ducting into the DC.

The channel in the floor should be quite deep to allow for the use of a Y plus a 45deg bend exits at floor level as hard 90deg bends reduce air flow.

The main workshop area in our men's shed is ~7 x 14 m and we are going for only one overhead trunk line down the middle and one down each side.

Originally Posted by asheddie

If this isn't practical then it can go to traditional piping above the machines. I just thought a system below would be out of the way and it would work better because the dust will be going with gravity.

It's actually a small disadvantage because the DC has to lift all the accumulated dust from all the ducting at the end of the connected runs. For overhead systems the accumulated dust is usually dropping down at that point.

Thank you for this advice. I feel we'll have to go for overhead ducting now as we won't be able to put trenches in the slab. It's a tricky situation with our lease. We have been granted a budget to build the shed, but were are going to be on a long term lease, there for have to get approval for major developments. The slab has to be one large pour, and our thought was piping coming up from the floor could always be cut flush and filled in later at minimal cost if we ever moved site, but I know we'd never get approval for large access channels. Bugger, I thought we were onto a good thing. BobL thats a very good point about the dusty having to lift the accumulated dust, we hadn't thought about that. QC Inspector, your idea sounds great, if we were owners of the site I would definitely put it to the committee tomorrow.
Thanks for the input guys. Looks like we'll be hanging the pipe around the walls and maybe down the centre of the shed also. The dusty will be in its own shed outside of the main shed at the back.
What are good brands of Dust Extractors for us to look at? up to around $5000.

Hi Ash,
I never read them all, but I hope someone suggested that you put the D/E outside, as they are very noisy, & upsets the Chaps that may have to work near it.
We have a rather big one, & Inside as well, to my mind the pipes are to small, should have gone 8" all the way to the back wall, some 20ft.then take 6in. off then 4in.
The way it is now, we have next to no Suction at the Lathe & Sanders.

When you get what you want, make sure you learn everything from the provider, as that is where I think we fell down.
In Plastic you will need a wire running to ground, & you will get a few saying piffle, but do it anyway, just in case of a bit of BOOM.

BobL seems to know a bit about these things.

Originally Posted by asheddie

What are good brands of Dust Extractors for us to look at? up to around $5000.

Use a Clearvue Max and you will only have to do it once. Have a good study of the Corrimal Men's Shed site for ideas and they will answer any questions you have.

Originally Posted by issatree

In Plastic you will need a wire running to ground, & you will get a few saying piffle, but do it anyway, just in case of a bit of BOOM.

BobL seems to know a bit about these things.

sorry to disagree but you won't need a ground wire. This has been discussed a few times before on this forum. Our men's shed has gone with the Clearvue Max and we are in the middle of the installation at the moment, albeit suspended for the holidays.

Hi Ash

to add to the above, the only services I'd consider putting in a slab is electrical power AND THEN only if I was confident within a half metre or so of where the major machines were to go.

Floor accessed services would be a significant trip hazard.

with a 12 x 12m shed, you have a reasonable amount of space. I suggest you divide that space into four zones:
1. wood machine "room"
2. bench "room"
3. kitchen / break area accessed from the bench room
4. metal work zone

use your $5000 budget on dust collection to service the wood machine room

plan on keeping the bench room clean with a combination of at tool extraction -- I'm thinking sanders, etc -- and a room filter.
I'll leave it to you to decide if the bench room contains a mitre saw, but I'd keep all the routers in in the machine room.


keep any extraction from the metal work zone separate from the wood machine extraction.


I'll defer to BobL, but perhaps use 8" or even 10" ducting for the trunk run.


enjoy your new shed

Originally Posted by ian

to add to the above, the only services I'd consider putting in a slab is electrical power AND THEN only if I was confident within a half metre or so of where the major machines were to go.

We went with two overhead flying fox wires with 15A sockets able to be swung in from each end plus we have 2 suspended 3P sockets in the middle of the floor. We can add more sockets if needed. With a 12 x 12 m space you may want to use 3 flying fox lead runs.

Floor accessed services would be a significant trip hazard.

if they are done right they should represent no more of a hazard than an expansion joint

with a 12 x 12m shed, you have a reasonable amount of space. I suggest you divide that space into four zones:
1. wood machine "room"
2. bench "room"
3. kitchen / break area accessed from the bench room
4. metal work zone

with a 12x12 you might find it difficult to have both 1 & 2
Our shed is about 12 x 19 m all up although that includes
4 x 6.5 m storeroom,
4 x 3m office and
9 x 4 m of kitchen, tearoom and ablution facilities, and
4 x 8 m garage for the senior citizens bus which has enough room to store 5 lathes on wheels
The main workshop space is ~15m x 8m but we can also move the bus and use the garage as temporary turning room while we are there.
We also have about 50m^2 of outside Tarmac space that we can wheel machines and even benches outside (under some shade) plus we have 4 outdoor market style umbrellas that are very useful to work under.

Metal working also needs dividing up between turning type activities and the rest so our metal lathes are in the WW area. This is not ideal but we have nowhere else for them. They are normally covered unless in use.