Thread: Dust extraction extra pipes?

Originally Posted by delbs

At this stage i am picking up the Carbatech 2HP economy extractor from a friend once he upgrades to his Hammer DC to match his C3 31

Carba-Tec® 2hp Economy Extractor : CARBA-TEC

Mate your setup is exactly what i want to duplicate, that looks great! Is it much louder running the DC ontop of the noise of your TS or jointer or thicknesser?

Also, i am getting that Carbatech unit for $200, if you guys can suggest a better more efficient unit than the carbatech model then please say so as this is all still in the design phase no money has been laid out yet. My budget would be up to $400 or so id say

Unfortunately you won't be able to duplicate what john has (ie 1000+ CFM, fully ducted, vented externally, with lots of bends etc) using a 2HP.
It's like trying to ask a 4 cylinder engine to perform like a V8 - it just aint going to happen
To maintain 1000 cfm a 2HP needs to be connected within a couple of meters of a machine and in as direct a line as possible. This means moving the DC between machines and limited chance for locating or venting the DC outside a shed.
If you want a fully ducted system that generates 1000+ CFM you will need at least 3HP and preferably a 4HP.

The cheaper 3HP units may also need some modifications.

Originally Posted by delbs

Not at this stage unless i go brand new. Price seems to jump dramatically for 3-5HP

For people out there with 4-5 machines in their shop. What is your budget usually?

My TWIN bag 3HP DC cost me a grand, and the ducting etc cost me about $500.
My DC enclosure is outside my shed and cost me under $100 but I had most of the materials for that otherwise it would have been maybe X2 more.
All up about 10% of the total construction cost of my shed.

My WIP is DC ducting here.
Details of 1.8 x 2.4 by 0.6 m sound reduction external enclosure are posted in my new shed fit out thread starting at post #127.

Originally Posted by delbs

At this stage i am picking up the Carbatech 2HP economy extractor from a friend once he upgrades to his Hammer DC to match his C3 31

Carba-Tec® 2hp Economy Extractor : CARBA-TEC

Mate your setup is exactly what i want to duplicate, that looks great! Is it much louder running the DC ontop of the noise of your TS or jointer or thicknesser?

Delbs,

BobL is right, of course. You need a 3HP dusty or a 5HP cyclone to achieve the magic numbers of 1000 CFM and 4000 FPM with a ducted system. Even then you must be careful with duct and hood design.

Noise can be an issue, but there is lots of advice on noise suppression available. Generally, when operating a noisy machine (like a planer) I can't hear the cyclone because the planer drowns it out.

Lots of blokes use the 2HP dusty. The drawback is that you really can't duct them and get satisfactory airflow.

this is really good feedback guys thank you.

ok so i need more grunt like a 4 or 5 HP dc to have it ducted.

As i would be using only one machine at a time i could get the 2hp with a flexi pipe and just connect it to the machine im using at the time? surely that would be better than my 1200W ryobi wet/dry vac at this stage

Originally Posted by John Samuel

Delbs,

BobL is right, of course. You need a 3HP dusty or a 5HP cyclone to achieve the magic numbers of 1000 CFM and 4000 FPM with a ducted system.

A cyclone is not a device capable of generating a flow (in fact it slightly restricts flow by about the same degree as a large twin needle felt bag filter) so it's not really a case of "one or the other"
Technically speaking a cyclone is a dust separation technology that if it is well designed doesn't impact much on (ie restrict) the flow of a working DC system.
The big advantage of a cyclone is that filter bags do not have to be cleaned and it can operate indefinitely without cleaning.

An efficient impeller in a real world workshop (ie ducting with a few bends and minor leaks in it, moderately well opened up machines/ports) driven by a
- 5HP motor should be able to pull 1800+ CFM in 6m+ runs of 8" ducting which would easily cover a big workshop and even two machines working simultaneously.
- 4HP should be able to generate 1600+ CFM in 6m+ runs of 6" ducting. This is probably borderline for two machines but excellent for a machine requiring a couple of inputs
- 3HP impeller will be limited to about 1250 CFM for <6m runs of 6" ducting.
- 2HP DC will be limited to about 800 CFM in <6m runs of 6" duct. To approach the 1000 CFM from a 2HP the DC must use a short length of 6" pipe to the machine, with; minimal junctions, clean bags/filters, no chip collectors, and machines and ports that are very well opened up. Its hard work but it's doable.
The important jump is going from 2 to 3HP because this will enable the DC to be located outside and still generate 1000+ CFM.
These are just rough guides, usually it will be worse than this.

Does it matter whether it's 800 or 1000 CFM, in some cases maybe not, because sometimes the geometry of a machine (EG a bandsaw)and the dust collection port arrangements dominates the effectiveness of dust collection. In cases like a big drum sander then multiple take off high volume dust collection becomes more important.

Originally Posted by delbs

this is really good feedback guys thank you.

ok so i need more grunt like a 4 or 5 HP dc to have it ducted.

A 3 HP unit can do short ducting and 1250 CFM

As i would be using only one machine at a time i could get the 2hp with a flexi pipe and just connect it to the machine im using at the time? surely that would be better than my 1200W ryobi wet/dry vac at this stage

The 1200 Ryobi W/D will be pulling maybe 120 CFM if the filter is clean. However, much of the fine dust will be passing straight through the filter and back into the shed, even worse, as these VCs age they can create more dust than they pick up.

Using the 2HP with (the 4" flexy connections removed), using a short length of 6" diam flexy, clean needle-felt or pleated filters, and the ports on the machines opened up to take and make advantage of 6" flex will approach 1000 CFM. However, the major drawback here is the DC is still inside the shed and DCs are notorious for leaks (and boy do they leak!) which simply delivers fine dust back into the shed - this the main reason why locating or venting a DC outside a shed is really worth doing. The other reason is the noise. Also emptying the bags while the DC is inside the shed is a PITA.

Originally Posted by delbs

As i would be using only one machine at a time i could get the 2hp with a flexi pipe and just connect it to the machine im using at the time? surely that would be better than my 1200W ryobi wet/dry vac at this stage

I am slowly in the process of putting together a 3HP dust collection system vented directly to outside. All my machines are on wheels with a stationary separator so I'll be wheeling each machine up to the DE unit and hooking it up with as short a length of pipe as possible.

Will you be collecting to a felt bag, fine filter or venting outside?

Originally Posted by delbs

ok so i need more grunt like a 4 or 5 HP dc to have it ducted.

Yes, the consensus would be at least 3hp. BUT!! Lets look at what power you have in the workshop and what else will be running at the time.

Delbs, Do you run any 3hp machines, eg tablesaw, bandsaw, thicknesser that you would be running the dust extractor at the same time as?

Often, the forgotten factor is the amount of power available in the work area. A 3hp dusty will have a 15amp plug and the power points in many home workshops will not even support ONE 15 amp appliance; a 15 amp plug will not fit into a regular 10 amp power point. The average garage has no more power availability that the average lounge room: that is a single 10 amp circuit with a couple of power points. To make it even worse, often the two power outlets in the garage are on the same circuit as the ones in the lounge and a couple of the bedrooms.

Now you CAN run ONE 15 amp appliance on a 10 amp circuit, provided that nothing else is plugged in anywhere else on the circuit and you know what you are doing. If the garage circuit is shared with outlets in the house what will Mum and the kids think if you unplug the tv, computers microwave, fridges etc so that you can run the dusty? They may have to be unplugged to save them from damage when the circuit is overloaded.

I am better off than most of us as far as power availability is concerned. I have a power subboard in the garage with two circuits, one has 8 10amp GPO's and the other is a single-outlet 15amp circuit which hangs from the ceiling in the middle of the shed. The previous owner was an electrician. The 15 amp circuit was for his welder. My point is that my main working machines (bandsaw, tablesaw and thicknesser are all 15amp 3hp machines, I have a 15amp compressor too but it is usually turned off when I am using other large appliances just so that it cant autostart and blow all the circuit breakers). I have nowhere that I can plug in a 15amp dusty as well.

The reality is that we have to work with what we have. Even with my generous power supply to my shed, I do not have the resources to run anything bigger than a 2hp dusty, if I want to run my other 3hp machines.

I would love to be able to run 3phase machines in the shed never mind just 15 amp, but the reality is that the cost of connecting 3phase to a domestic property is prohibitive.

It is all very well to say that we should all have at least 1200cfm being pulled through 6" pipes and vented outside. I totally agree. We all should. But the reality is that most of us cant! At least not at the same time as we are running the tools we need to run to do what we need them to do.

This is why I mounted everything on mobile bases so that I can locate them under the 15amp power point and connect them to the 2hp dusty when in use. I am modifying the dust collection system as a current project to get it to pull through a 2.5m duct with one 45 degree bend leading into the cyclone then sucked straight out the top of the cyclone and out the side of the shed. the only obstructions are the cyclone and the 45 degree bend.

I hope it will prove satisfactory, not as good as using a bigger dusty of course, but I am doing the best that I can with the resources I have

Doug

Its interesting that you mention power as i just had a mate thats a sparky over for a cashie recently. I asked him to take a quick look into the garage as according to my building plans the garage was build roughly 11 years after te house was built. It turns out the original owner was an electritian also. He installed a ducted Vac system and an intercom sys throughout the house along with a dedicated 32amp circuit into the garage with its own breaker. 4 or 5 power points and 1 of them 15amp. I dont have a 3phase circuit installed through so im obviously not running any machinery that requires 3phase.

Can i ask what brand is the hanging pendand power plug hanging from the roof in your workshop? I have a home made solution at the moment for my Jointer and table saw but do need to put in a proper pendant from clipsal or something

That being said i havent run all of my machinery at once and tripped the power yet. Thankfully it is seperate from the rest of the house so the wife can continue watching tv,internet etc and i can continue to tinker in the workshop.

As its a doublebrick garage I would have to punch a hole through the wall inorder to put the DC outside so at this stage i will try to keep it inside but if i do experience leaking or other problems then ill look into my options of putting it outside.in some form of housing

At this stage with the tools that are available to me (the 2HP dusty from my friend) i will keep the 2HP dusty inside and just run flexible piping to each machine as i need it, maybe a dust deputy also.

Thanks to all for discussing this, has helped me understand what my options are and what other people have in their garage. Its great!

I agree with doug about the power situation as an issue to consider.

As its a doublebrick garage I would have to punch a hole through the wall inorder to put the DC outside so at this stage i will try to keep it inside but if i do experience leaking or other problems then ill look into my options of putting it outside.in some form of housing.

The problem with this approach is you just won't always know if your DC is leaking. Some leaks are clearly visible, some are much less so and cannot be detected without a particle detector. Some leaks are induced by just moving or bumping the DC slightly ie tugging it via the flexy or just disconnecting and failing to reconnect properly. This is why it is better to locate the whole (or at least the pressurised side) of the DC outside a shed.

At this stage with the tools that are available to me (the 2HP dusty from my friend) i will keep the 2HP dusty inside and just run flexible piping to each machine as i need it, maybe a dust deputy also.

I wouldn't use a dust deputy or any type of chip collector with a 2HP DC, these things slow the flow down of what is already a marginal DC.
I'd learn to live with keep emptying the bags to maximize the flow.
I presume you are going to use 4" flexy?
If so then my experiments show that a basic chip collector on 4" flexy slows a 3HP DC down from 400 cfm to 275 CFM - this is a serious loss of flow.
It will be similar for a 2HP unit since the use of 4" ducting is the initial limiting factor.
I would put my energies into modifying the DC and machines to be able to use 6" flexy since that will give you THE greatest boost in flow and dust collection over any other factor.