Recky33
Established Member
Dan, How much room will you have around the extractor when you get it and its in place ?
Allan
Allan
If you're exhausting air from your DE outside...
- Thread starter goldeneyedmonkey
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goldeneyedmonkey
Established Member
I'm not sure yet Allan, I'm currently moving from a cellar/ workshop into a bigger garage/ workshop (it's about 5m square) but I've also bought a lot more machinery to go in there as well. I really need to work out the layout soon and start building up a decent bench/ assembly table and a run of cupboards now you come to mention it.
_Dan.
_Dan.
FWIW, our heat-recovery unit is made by a firm called Genvec. Must have got some more details about it somewhere - OP can you PM me if you want me to hunt them out?
goldeneyedmonkey
Established Member
Cheers Dick, a friend of mine is apparently going to research this for me. I've told him about thermal wheels and the other type that a few companies do. Thank you for the offer though.
Cheers_Dan.
Cheers_Dan.
Recky33
Established Member
Hows about, if you remove the filter from the extractor and connect a pipe that fits where the filter fits, then get hold of a plastic bin with lid, cut a hole in the lid so the pipe can go through it, drill some holes around the top of the bin so the air can get out and then put 2 foot of water in it, as long as the pipe is below the surface of the water it will act just like a hooker, all the dust will mix with the water and the clean air will enter the workshop via the holes round the top, given that theres a cyclone on the one your thinking of getting theres not going to be a hell of a lot of dust getting down to the bin anyway so shouldnt need emptying for months, and flexy pipe from a hydroponic shop is well cheap for the size and amount needed, If it works theres no need to reclaim heat as its still in the shop.
Hmmm might have just talked myself into making one, soon as it warms up a bit
Allan
Hmmm might have just talked myself into making one, soon as it warms up a bit
Allan
goldeneyedmonkey
Established Member
Recky33":2kd5rp4o said:
now Allan, that to me, sounds like a genius idea. Well played that man
Would this mean that I'd have a constant bubbling of water in the the bin then? That could prove to be pretty loud I think? I'd have to do some soundproofing somehow I reckon. As I've not got the unit yet, I don't know how the exhaust system works, and what I'd need to connect up to it to make this feasible. But I'll definitely be having a look when I get it. Thank you.
_Dan
promhandicam
Established Member
It sounds like you are trying to create a clean room rather than a workshop! According to this website http://www.coastwidelabs.com/Technical Articles/Cleaning the Cleanroom.htm the biggest problem you are likely to face in your sterile environment is you!
Lots of useful information in the link :wink:
Lots of useful information in the link :wink:
It's a bit of awkward issue this one. Exhausting is one way to avoid filter issues, but I'm not too sure how those thermal wheel deals (which have been around for a long time) might cope with dust. A good cyclone should get the levels down very low though. It may be the makers have application experience.
Another issue is that if you forget to empty your dust bucket in time then large quantities of chips will get carried over and through the cyclone into it....
The alternative is sufficiently fine filtration (at least HEPA 15), but this it seems requires a very efficient cyclone to not suffer problems with filter blinding and consequent loss of efficiencies and cost.
Even these filters allow a small part of 1% at the very fine end of the dust particle spectrum to be carried over, and I've no idea how big a deal in H&S terms that might be.
It's in a sense the $1m question. Here's Bill Pentz's page on dust level testing (done with an expensive meter before the Dylos unit came available) which is sobering reading http://billpentz.com/woodworking/cyclon ... esting.cfm
He says on that page that just turning on most dust systems fitted with coarse standard (bag?) filters is more than enough to drive suspended dust levels in a shop way over the relatively high OSHA permitted level of 5mg/m3. This is also why box filter units that try to screen dust out of the shop air sound dodgy.
He goes on to say that the much tighter medically derived ACGIH/industrially permitted level of 0.1mg/m3 is only achieved by his own cyclone fitted with high quality filters (see his site for details, but that basically means HEPA 15 or better) and one other exhausting outside - both shifting lots of air volume by running large 5hp fans and 6in ducts, and only with properly modifed hoods on most machines.
Both Bill and Clear Vue also present the results of professional lab testing of his cyclone system, but they don't seem to be linked to likely shop dust levels and so it's in the end it's down to his word for workshop measurements. The point in favour of his objectivity is that he only got involved in this whole ball of wax as a result of serious health problems, and he has not gone commercial. There's been many people post of achieving excellent results with his design.
One technical point in his favour is that it seems his cyclone uses dimensions long since approved by the US body developing standards for fine dust separation in US industry in general, and subject to regular testing. This is not the case with all other cyclones - the commercially available woodworking units seem to use much shorter and dumpier designs with a simplified right angle inlet - I imagine for economy in storage, shipping and material usage.
Another issue is that if you forget to empty your dust bucket in time then large quantities of chips will get carried over and through the cyclone into it....
The alternative is sufficiently fine filtration (at least HEPA 15), but this it seems requires a very efficient cyclone to not suffer problems with filter blinding and consequent loss of efficiencies and cost.
Even these filters allow a small part of 1% at the very fine end of the dust particle spectrum to be carried over, and I've no idea how big a deal in H&S terms that might be.
It's in a sense the $1m question. Here's Bill Pentz's page on dust level testing (done with an expensive meter before the Dylos unit came available) which is sobering reading http://billpentz.com/woodworking/cyclon ... esting.cfm
He says on that page that just turning on most dust systems fitted with coarse standard (bag?) filters is more than enough to drive suspended dust levels in a shop way over the relatively high OSHA permitted level of 5mg/m3. This is also why box filter units that try to screen dust out of the shop air sound dodgy.
He goes on to say that the much tighter medically derived ACGIH/industrially permitted level of 0.1mg/m3 is only achieved by his own cyclone fitted with high quality filters (see his site for details, but that basically means HEPA 15 or better) and one other exhausting outside - both shifting lots of air volume by running large 5hp fans and 6in ducts, and only with properly modifed hoods on most machines.
Both Bill and Clear Vue also present the results of professional lab testing of his cyclone system, but they don't seem to be linked to likely shop dust levels and so it's in the end it's down to his word for workshop measurements. The point in favour of his objectivity is that he only got involved in this whole ball of wax as a result of serious health problems, and he has not gone commercial. There's been many people post of achieving excellent results with his design.
One technical point in his favour is that it seems his cyclone uses dimensions long since approved by the US body developing standards for fine dust separation in US industry in general, and subject to regular testing. This is not the case with all other cyclones - the commercially available woodworking units seem to use much shorter and dumpier designs with a simplified right angle inlet - I imagine for economy in storage, shipping and material usage.
goldeneyedmonkey
Established Member
I've looked over Bill's pages before, but it was a lot to take in and get my head around. There NEEDS to be a simple guide telling people what the real deal is, lab testing carried out, and approved machines/ systems. We should start a petition. Or rather someone who holds more authority/ respect should start the ball rolling.
It wouldn't take much, just participation, and oh yeah, making the government stump up some money (in this economic climate) to fund the research. Or get funding from elsewhere.
ha-ha! _Dan.
It wouldn't take much, just participation, and oh yeah, making the government stump up some money (in this economic climate) to fund the research. Or get funding from elsewhere.
ha-ha!
_Dan.Bill is mind bendingly wordy, and not very well structured. Most of the info is there, but where? For me it seems to underline his good intentions though.
Another consolation is that while I've seen reports by now of many people building his systems (Clear Vue forums and other pages), I don't think I've heard of one that wasn't dead pleased with the performance. There's even been a few converts on the US felder owner's group.
Any hiccoughs seem mostly to be down to people building in funnies.
The industrial scene seems to be reasonably tightly regulated in this regard, although I don't know if there's much enforcement. The hobby/DIY stuff sneaks in under the regulatory radar, and as a result anything seems to go....
Another consolation is that while I've seen reports by now of many people building his systems (Clear Vue forums and other pages), I don't think I've heard of one that wasn't dead pleased with the performance. There's even been a few converts on the US felder owner's group.
Any hiccoughs seem mostly to be down to people building in funnies.
The industrial scene seems to be reasonably tightly regulated in this regard, although I don't know if there's much enforcement. The hobby/DIY stuff sneaks in under the regulatory radar, and as a result anything seems to go....
matt
Established Member
On the subject of the outlet via water... Something I'd considered in the past but figured the water would kill any flow and thus reduce the ability to to capture at source. Perhaps an alternative is to use a humidifier to create a very moist atmosphere, although the velocity of the air travelling through the container would probaly mean it getting blown out before it has much effect. Perhaps feed the humidifier in the to final section of outlet hose to ensure some mixing occurs?
Perhaps we should exhaust in to a burner instead Power a furnace from the DE so when your extraction is on, your heat goes up to compensate...
Perhaps we should exhaust in to a burner instead
Power a furnace from the DE so when your extraction is on, your heat goes up to compensate...
Sportique
Established Member
Just thinking outside the box (sic).
How about using infra-red heaters? I think I am correct in saying that such heaters do not heat the air? - only living flesh :lol:
Thus avoiding the issue of heat loss when dumping outside?
They also work quite quickly (but not cheap to run)
Dave
How about using infra-red heaters? I think I am correct in saying that such heaters do not heat the air? - only living flesh :lol:
Thus avoiding the issue of heat loss when dumping outside?
They also work quite quickly (but not cheap to run)
Dave
To your thought Matt - how's about setting up the chip bin under your cyclone to discharge through a rotary valve or auger (to get control of the feed rate, and prevent flash back) into a burner? There's lots of wood burning furnaces and related hardware available now from the bio fuels/wood chip/pellet boiler industry - which might open up the possibility of hooking your wood chip burning into a domestic heating system.
Infra red heaters are for this reason (the high throughput of air) used in automotive spray booths Dave, so that's a definite option. Radiant heat is absorbed by most surfaces, and then re-emitted as they warm up - with the amount determined by much heat the surface takes up/does not reflect. e.g matt black is the best. I'm not sure how comfortable -8 deg C air and lots of radiant heat would be - but it could well be fine.
Paint booths for many years used water curtains to filter out overspray from exhaust air, but they have largely been phased out - I think possibly because of the large volumes of contaminated water (effluent) they produce. Maybe wood dust would be OK in this regard. You run into all sorts of issues with potentially hazardous biological growth in it though too (legionnaires disease and the like), and this necessitates treatment with what (at least back in the 80s) were some nasty and quite toxic biocides. (the issues are well known from experience with humidifiers and open cooling towers in industry)
It seems likely from industrial experience that just bubbling the air through water in a bucket wouldn't expose enough surface area to the air to do the job right - at least not unless some sort of diffuser was used to create very fine bubbles.
The other issue with water is that whatever air goes through it will end up very wet, potentially even saturated or at 100% RH - so recirculation isn't likely to be an option unless you fancy a sauna.
My personal view is though that there's one heck of a lot to be said for exhausting your air for as along as is possible - for all the b****t about high efficiency HEPA filters and cyclones (and they seem to be as a good a solution as there is at present if you have to recycle) there's a doubting side to my thinking too.
The other major difficulty is that even if you exhaust everything it's very hard to see how it's possible without very finely tuned hood designs and set ups to avoid losing dust into the air when cutting, or indeed to avoid stirring up old dust. The clean room joke might be more accurate than we would like to admit.....
Infra red heaters are for this reason (the high throughput of air) used in automotive spray booths Dave, so that's a definite option. Radiant heat is absorbed by most surfaces, and then re-emitted as they warm up - with the amount determined by much heat the surface takes up/does not reflect. e.g matt black is the best. I'm not sure how comfortable -8 deg C air and lots of radiant heat would be - but it could well be fine.
Paint booths for many years used water curtains to filter out overspray from exhaust air, but they have largely been phased out - I think possibly because of the large volumes of contaminated water (effluent) they produce. Maybe wood dust would be OK in this regard. You run into all sorts of issues with potentially hazardous biological growth in it though too (legionnaires disease and the like), and this necessitates treatment with what (at least back in the 80s) were some nasty and quite toxic biocides. (the issues are well known from experience with humidifiers and open cooling towers in industry)
It seems likely from industrial experience that just bubbling the air through water in a bucket wouldn't expose enough surface area to the air to do the job right - at least not unless some sort of diffuser was used to create very fine bubbles.
The other issue with water is that whatever air goes through it will end up very wet, potentially even saturated or at 100% RH - so recirculation isn't likely to be an option unless you fancy a sauna.
My personal view is though that there's one heck of a lot to be said for exhausting your air for as along as is possible - for all the b****t about high efficiency HEPA filters and cyclones (and they seem to be as a good a solution as there is at present if you have to recycle) there's a doubting side to my thinking too.
The other major difficulty is that even if you exhaust everything it's very hard to see how it's possible without very finely tuned hood designs and set ups to avoid losing dust into the air when cutting, or indeed to avoid stirring up old dust. The clean room joke might be more accurate than we would like to admit.....
RogerS
Established Member
Aren't we in danger of going a bit OTT on this? Surely there is as much dust thrown out by whatever cutting device you're using as what gets sucked down the tube.....especially thinking of an SCMS.
barkwindjammer
Established Member
promhandicam
Established Member
RogerS":1enw1kpo said:
Too late I fear. The OP seems to be most concerned about the finest dust - the sort produced when de nibbing or final sanding both of which need to be done by hand if you want a half decent finish. Then of course if you want to remove all the dust from the grain prior to applying the first coat of finish the ideal tool is an airline. IMHO, it seems that the OP has tried to buy the best chip / fine dust extractor he can which captures 99% of the dust it picks up (not the same as 99% of dust in the workshop). As long as sensible precautions are taken - regular vacuuming and a decent respirator for hand sanding I think that is as much as anyone could seriously expect - but what do I know :roll:
Merry Christmas to all the other sad sacks trawling the woodworking forums on Christmas eve!
Steve
Stoday":irvl5781 said:
These guys do it professionally; http://www.elixair.fi/pdf2/industrial.pdf
Heat exchangers not needed when you filter the air so well you can return it to the shop.
I've got Elixair E400 in my garage shop running 24/7 to trap all the small stuff floatig around (I've got bag type extractor for the powertools). About every two weeks I run the platecollector through dishwasher cycle and vacuum the coarse & carbon filter.
In case of home heat exchangers would recommend plate type instead of rotation, as the rotating also return some "dirty air" back indoors.
That's dead interesting guys, especially if it was possible to arrange one in line in a duct after the cyclone. Depending on how quickly it blinds up it I wonder if it might (with a high quality cyclone) make it possible to run without filters at all???
Harold Pomeroy
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I have a dust collection system vented to the outdoors, with no return air. I have been running this way for 15 years. Before that I worked in dusty shops.
Make up air comes from the upwind side of the building, dust vents downwind. I work alone in a professional shop. I use all wood, no plastic, plywood, laminate, or other miracle plastic wood replacements.
Dust Collectors 11" inlet blower for planer, tenoner, jointer, shaper and rip saw. 6" blower for rabbeting saw, rip saw, shaper, and tenoner. Central vac nented to exterior for rip saw, hand sander, cleaning the floor, mortiser, miter saw, router, and anything else. I run these alone or in combination. The venting is to a trailer. The fine dust land in the field behind the shop.
Heat I'm in New Hampshire, United States. I heat from October to April. Heat is provided by a propane furnace, which heats water circulated through the concrete floor. Yesterday it was 15 degrees (F) outside, and 60 (F) inside.
The one problem I have with this system is that the shop is low pressure, and I can't run a wood heater in the shop. The smoke gets pulled down the chimney. The gas furnace has to be sealed combustion.
The point of this post is to show that venting to the exterior can work. It takes some creativity and understanding of dust collection. I hope that this information can help others set up decent systems. The information from dust collection manufacturers often points to profit oriented solutions. Those so-called solutions get repeated as fact on forums.
Harold Pomeroy
Make up air comes from the upwind side of the building, dust vents downwind. I work alone in a professional shop. I use all wood, no plastic, plywood, laminate, or other miracle plastic wood replacements.
Dust Collectors 11" inlet blower for planer, tenoner, jointer, shaper and rip saw. 6" blower for rabbeting saw, rip saw, shaper, and tenoner. Central vac nented to exterior for rip saw, hand sander, cleaning the floor, mortiser, miter saw, router, and anything else. I run these alone or in combination. The venting is to a trailer. The fine dust land in the field behind the shop.
Heat I'm in New Hampshire, United States. I heat from October to April. Heat is provided by a propane furnace, which heats water circulated through the concrete floor. Yesterday it was 15 degrees (F) outside, and 60 (F) inside.
The one problem I have with this system is that the shop is low pressure, and I can't run a wood heater in the shop. The smoke gets pulled down the chimney. The gas furnace has to be sealed combustion.
The point of this post is to show that venting to the exterior can work. It takes some creativity and understanding of dust collection. I hope that this information can help others set up decent systems. The information from dust collection manufacturers often points to profit oriented solutions. Those so-called solutions get repeated as fact on forums.
Harold Pomeroy
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