Upgraded Dust Extraction

[PAC1]

Over the last year or so I have come to the conclusion that my dust extraction system was inadequate. I had started out with a WV2 LVHP vacuum which are very good vacuums collecting small particles. However I was asking it to extract from my 16" planer thicknesses, a 12" table saw, spindle (all in a combination machine), a band saw and a mitre saw. So I added a collection bagging system and 115mm drain pipe as ducting. To say it was struggling is an understatement. Having read as much as possible on the subject including Bill Penz excellent research I realised that I may as well not bother collecting any as only collect 75 to 80% when looked at from a health point of view.
This year I decided to do something. The choices were either go for a Chip collector that would spew the fine dangerous particles all over the workshop, go for a clean air system which would cost a fortune or put the system outside. Having read about the chip extractors the best I could find was the Jet DC1100: http://www.axminster.co.uk/jet-dc1100a- ... ckage-deal. It offered the air movement rate that could achieve clean air but still spewed the fine dust back into the workshop so I decided to put it outside. I also read about ducting and learnt that bends are bad. In fact so bad that if you had say three bends you were wasting your time installing ducts so I had to work out how to connect a Jet DC1100 to the duct system. I also read that 6" ducting really is the smallest size we should consider if we want clean air.
The solution was to hang the motor and fan of the DC1100 from the ceiling and connect the ductwork straight into the fan port thus eliminating two bends. The next problem was that the vortex cone collector and filter were now further away from the fan so I installed more ductwork from the fan to the collector. This is all outside in its own little shed. The downside with a system like this outside is that it is sucking the equivalent of 18 air changes per hour from my workshop.
I still have one bend as the ductwork comes from the ceiling down to my combination machine but that is a very slow bend and doubles up as an access hatch if the system blocks.
I finally got all of this installed and running and spent a day machining up a large pile of oak. The good news is that it works very well. It is providing the sort of air flow that keeps the workshop clean, there were no blockages and it coped with the air changes (I must have a leakier workshop then I thought).
The point of the thread is simply to say that we all need to review our dust control systems from time to time. Sometimes we find that what we thought was adequate or something we could live with turns out to be inadequate and from a health point of view worse than doing nothing. The problems are resolvable without spending a fortune.

 

[user 19915]

Any photo's have you used plastic ducting with blast gates ?? Iv'e bought the same dust extractor as you but haven't given it a good test yet i used 6 in drainage pipe with 4 in drop off.s and 5 or 6 different blast gates when i finish ill have to think about grounding the system
mock

 

[PAC1]

Sorry no photos at the moment. I am not sure what the photos would show as the outside cupboard/shed is very compact and a line of metal ducting is not that exciting. If there is interest I will take photos on Saturday and put them up. I very nearly went with 6" drain pipe having used it previously and found it both cost effective and efficient as there were no leaks but decided to use metal spiral duct and a large radius extra thick clipped bend when I found you can swap between spiral and clipped. However it leaked like a sieve so I have wrapped duct tape around everything that could leak. I will probably wrap the whole of the Y as it is spot welded and leaks everywhere. I used metal blast gates from Axi. I have kept it at 6" to the combination machine otherwise you loose to much air flow as a 4" is half the cross section area of 6" and 4" is not enough for the machine. I have a 4" drop to my bandsaw which seems fine to me but everything I have read says the bandsaw needs 6" as well.

 

[PAC1]

I never grounded my old drainpipe system!

 

[user 19915]

No don't go out of your way for photo;s i was wondering if you grounded the pipe work and hoping for a few idea;s but iv.e nearly finished my ducting but i haven;t grounded anything and was wondering if i should as im only using the machines 2 /3 times a week as a hobby
Mock

 

[PAC1]

I think there is a screw on the casing of the fan on the Jet you can use to ground the ductwork. At least I could not think what else it did If you are so minded.

 

[John933]

That's one of the thing's that is near to next on my list. Been looking at You Tube. Seen a chap who has made one, and it work's well. To me it's a case of time and an old washing machine from the dump. For the motor, pullie system, and the controller. Then it's a case of make it as big as you want.
John933

 

[AES]

Very interesting thread PAC1, thanks for posting.

I'm also in the middle of trying to sort out dust extraction/filtration in a cellar, with no/very limited chance of doing anything outside. Like you I've been watching loads of stuff here, on other sites, on Youtube, etc, but I have got myself somewhat confused in some areas, so please forgive me if the first Q sound sarcastics - I can assure you it isn't meant to be.

1. Why not just suck air from inside the shop, filter it (HEPA), then blow it back out into the shop? Several people on Youtube seem to be doing just that, some with and some without the Thein/cone to separate the "lumps" from the fine dust, which I do appreciate is a separate step in the whole process.

2. What are the rough dimensions of your shop please?

3. If you don't mind saying, what was your rough cost for everything in your upgraded system (materials only, not labour)? Not only I am still trying to decide exactly what to do /how to do it, but am also trying to decide if I should "waste" time making or simply buy stuff like an extractor/impeller, etc.

Thanks in advance

AES

 

[PAC1]

In answer to the questions:
1. I thought long and hard over this one before making the decision. The problem is that it is the very fine dust that is the killer the bigger lumps and chips we can either add to our diet or spit out. Therefore when you think about it you either need to have excellent HEPA filters 99% + of 0.3mu which was going to be expensive because you pay for the filter and need stronger motors to push the air through the filter. The cost of a decent extractor was over £2k by the time you get the HEPA filter. Or extract to the outside then it does not matter if you only have a 5mu filter and you can get away with a 1.5hp motor. I think a separator is the only sensible choice where ever you vent to. I went with the Vortex cone.

2. My Machine shop is two double garages 5.5m square giving a volume of 75m3. I also have a bench shop of 10m x 3.3 but that has doors to separate it.

3. The Jet DC1100 was about £580 including a 1mu filter and the 150mm metal ducting was circa £500 with all the brackets and fixings etc. The expensive part of the ducting was a special slow bend I had made £60 and then the cost of brackets. If you use strapping rather than special brackets I think you could knock off close to £100. You could do the ducting cheaper in drain pipe which is actually a very efficient material to use. So for about £1k including VAT I have what seems so far to be a very clean machine shop. I looked at making the extractor but I am not too mechanically minded so for me it was £580 well spent.

I now have an airflow tester so hope to check the flows I am actually achieving.
hope this helps.

 

[AES]

Thanks a lot for the answers PAC. Another dust collection thread bookmarked!

I see what you're saying about the filtration side of things, but "fortunately" my shop is MUCH smaller than yours, so perhaps (just maybe) I could get away with a smaller/lower power & therefore cheaper machine. And I don't have a TS or TP either, my main problem is sanding.

Venting to outside is not 100% impossible for me but very nearly so - the whole cellar/basement is made out of reinforced concrete and includes a nuclear fallout shelter - yes, really (pretty much standard here). Apart from the doorway into the house itself, there's a single doorway to a set of steps leading to ground level and 2 small windows with their lower cills at ground level (i.e. about 3/4 s of the way up the inside cellar walls. BUT there is the outlet from the fallout shelter though - completely in the wrong place but it IS there! :?

Clearly I've got some more thinking and info collection to do, but as above, thanks a lot for your prompt answers.

Cheers
AES

 

[PAC1]

I measured the Cfm and flow rate this afternoon.
The 150mm duct achieves 559cfm and 4231ft/m
The 100mm duct only achieves 248cfm and 3046 ft/m
I am pleased with this but it does show that the high volume low pressure systems are not good when you start reducing the duct size.

AES if sanding is your main issue you actually need more not less cfm. Most sanders seem to spread dust everywhere. You might actually be better with a vacuum system such as Camvac

 

[PAC1]

The good news for those thinking about a Jet Dc1100 my figures at 559cfm equate to 950 m3/hr against the very theoretical 1650m3/hr in the Jet specification. I do not think this is bad at all given all I have read on the differences between theory and reality once you fit a fine filter and ductwork.

 

[Alf Beharie]

In answer to the questions:
1. I thought long and hard over this one before making the decision. The problem is that it is the very fine dust that is the killer the bigger lumps and chips we can either add to our diet or spit out. Therefore when you think about it you either need to have excellent HEPA filters 99% + of 0.3mu which was going to be expensive because you pay for the filter and need stronger motors to push the air through the filter. The cost of a decent extractor was over £2k by the time you get the HEPA filter. Or extract to the outside then it does not matter if you only have a 5mu filter and you can get away with a 1.5hp motor..I think a separator is the only sensible choice where ever you vent to. I went with the Vortex cone..

Don't you mean a Cyclone?

2. My Machine shop is two double garages 5.5m square giving a volume of 75m3. I also have a bench shop of 10m x 3.3 but that has doors to separate it.

3. The Jet DC1100 was about £580 including a 1mu filter and the 150mm metal ducting was circa £500 with all the brackets and fixings etc. The expensive part of the ducting was a special slow bend I had made £60 and then the cost of brackets. If you use strapping rather than special brackets I think you could knock off close to £100. You could do the ducting cheaper in drain pipe which is actually a very efficient material to use. So for about £1k including VAT I have what seems so far to be a very clean machine shop. I looked at making the extractor but I am not too mechanically minded so for me it was £580 well spent.

I now have an airflow tester so hope to check the flows I am actually achieving.
hope this helps.

Methinks that perhaps you could have done a bit more research before making your decision? For example, rather than investing in one very expensive yet inefficient dust extraction system you could have gone for much more efficient system using separate extractors for each machine, for the same money!
For instance, the Scheppach ha1000 filters down to 0.3 Microns as standard, it's very compact, is cheap on the electric bill as it only has an 1100 watt motor, its relatively quiet (77 dba) it has tonnes of suction for its size through its 100mm hose inlet yet its also very cheap to buy (around £100). So for the £580 you spent on the Jet you could have had 5 ha1000's!
Add 5 separate cheap 50mm bore Cyclones to keep the fine dust from reaching the ha1000's ultra fine filter in the first place, plus hoses, cuffs and adapters as necessary and you probably could have had change out of the additional £500 you spent on the ducting alone, had much cleaner air in the workshop and a far more efficient system as a whole.
The biggest problem we face in the UK, dust extraction wise, is an almost total lack of access to off the shelf Cyclones that can take 100mm hose natively (which is why I only have a 50mm bore hose version).
The only UK based company I could find offering a Cyclone with 100mm hose fittings is a DIY assembly kit in a mixture of clear Polycarbonate and Perspex, which you have to glue together yourself, from a company called cyclonecentral.co.uk....The kit costs £110.
You can get injection moulded versions with 150mm (6") hose fittings for £125 (Omnipole in Croydon currently have two knocking round their warehouse) and these would be right up your ally so to speak...I've seem the same ones on ebay for £150 from other vendors.
I am so sold on the performance of Cyclones since trying them I would actually love to go into the business of making them!
This is my current Cyclone setup, an Omnipole Omni ICE. The bent hose on the top outlet of the Cyclone is an ASR 120 degree Polyester reinforced Silicone car induction hose, which acts as a strain relief...Everything fits as tight as a glove so there is no need for jubilee clips:

 

[PAC1]

Alf
Unfortunately you need to check your research. Your Scheppach sucks a theoretical 183M3/hr which is about 107cfm. The Jet DC 1100 Vortex Cone has a theoretical 1650m3/hr which is about 950cfm. You will find that your 183m3/hr is not achieved in fact and when you add a cyclone you probably loose 1/3 to 1/2 the suction in turbulence. The Scheppach could not even begin to clear my 16" planer even if stood next to it. So thanks for the suggestion but By my calculations I am much better off with The Jet. Further I took out a WV2 with a Large separator in order to install this system.

 

[AES]

Thanks PAC.

QUOTE:
AES if sanding is your main issue you actually need more not less cfm. Most sanders seem to spread dust everywhere. You might actually be better with a vacuum system such as Camvac
UNQUOTE:

Yes, thanks I understand that (basically !), but as I'll be dealing with a smaller area overall than yours I think (read "hope"!) that I won't need quite such a big machine as yours. Re the Camvac idea, yes, and I already have a Karcher which sucks very well and is brilliant at extracting direct from hand-held tools or from my router table (by luck I seem to have hit on a pretty good extraction system coupled both underneath and to the fence) but the B - - --- Y Karcher is so loud that I can't (for example) hear the phone ring or the radio (both actually in the cellar with me).

That's not too much of a problem for something that you only use now and again, but as age draws on and my back isn't getting any better I see myself spending more and more time sitting with a scroll saw running more or less permanently, for which sanding or rounding over for Intarsia (small Dremel drums, or small bits on the RT) is also then required, often for quite long periods.

I also have a cheapo (Lidl or Aldi) ashes vac permanently connected to a small bandsaw and that does an adequate job of extracting cutting dust (no cone or Thein fitted to it as yet - later), and although it's a bit quieter than the Karcher it still drowns out both the phone and the radio.

At the back of my mind there's a "weird idea" slowly germinating - my nuclear fall out shelter has a (hand-crank) air extractor/filter and I'm wondering if I can "butcher" that - if it can filter out nuclear fallout it should be OK on dust, even MDF dust!

Mind you what the Civil Defence people will say when they next come round for their 3 year inspection I don't know! And it's also designed to cover a volume of 12 cu. Metres (3 people max) in the shelter itself, not the whole cellar. Whereas I really need to cover the whole cellar (162 cu. Metres)! Clearly much thinking still to be done.

Thanks also for the points you raise Alf - all grist to my mill, and I'll get there "one fine wet day" as my old man used to say.

As always this Forum is great when people lay out their own experiences and problems for those of us "following along behind". Thanks

Krgds
AES

 

[user 19915]

Well iv;e got to be honest i bought the Jet DC1100A Extractor and Filter Cartridge - PACKAGE DEAL and wasted my money on 6 inch ducting with 4 inch drop offs about 12 feet of ducting altogether and it;s crap i should have stuck to 1 100 mm flexi and change every time i use a different machine