Dust extraction

[evoman76]

After some more advise, whats the best sort of dust extraction for a small hobbies workshop, need it for my lathe, bandsaw and belt sander. Such a minefield !

Thanks

David

 

[MARK.B.]

Do a search on here and you will find loads of advice on almost every question you could think off ( and many you would never have thought to ask ), just one thing to remember, after you have paid for and installed your extraction Remember to use it 8-[

 

[sploo]

After some more advise, whats the best sort of dust extraction for a small hobbies workshop, need it for my lathe, bandsaw and belt sander. Such a minefield !

Thanks

David

There are many different ways to skin the cat: depending on your budget and workshop space.

On the budget end, you could go for what I'd call a "chip extraction": that is; just about any cheap "dustbin" style extractors that will collect chips. They will basically act as a dust pump in terms of (not) capturing the dangerous fine dust, so a powered respirator such as the Trend Airshield would be advisable (which is also good for the lathe as it offers face and head protection).

On the above, you could add a workshop air filter, to try to take the dangerous fine dust out of the air.

At the other end of the scale, a full sized cyclone extractor will separate chips and only send the finest (dangerous) dust through a high quality filter, but you're likely looking at a 3-5hp motor (with appropriate mains requirements), and a very tall ceiling requirement.

A smaller cyclone or DIY Thien baffle may be more practical; especially if you can vent the exhaust outside rather than try to filter and recirculate.

Finally, actually capturing the dust at source can be hard; the machines need to be well designed (most aren't) and many extractors will not provide enough airflow (either volume or speed) to capture dust - especially if used over ducting runs or long lengths of 4" hose.

 

[MikeJhn]

For the best advice read this first: a-guide-to-dust-extraction-by-member-siggy-7-t102025.html then make up your own mind.

Just one point on cyclone/Thien Baffles and the like, their only function is to help prevent find dust getting to the main suction machines filter and therefore delay the cleaning of same, you can not use a collection bag with them due to their function, therefore when you empty them you are exposed to the fine dust you where trying to avoid, for fine dust its far better to use a vacuum cleaner type devise with a bag and good filter, Numatic vacuums have the facility for up too four filters and an additional HEPA filter if you feel the need.

Large chips are a totally different matter, read the above link and you will then be in a position to make up your own mind.

Mike

 

[ColeyS1]

Do you think you may ever add to your tool arsenal ? Perhaps adding a planer thicknesser, router or a table saw ?
If that were the case, I'd be tempted to have 2 different extractors. For the hand tools, a hoover type extractor, the larger the hose on it the better.
For your lathe, bandsaw and any other machinery, something with a 4 inch hose might be more suitable.
When I first started playing on the lathe, I was determined I wanted to do it cleanly. The ultimate goal being to have no chips or dust flying anywhere. Even connected up to a humongous extractor I was never completely happy with the extraction. Perhaps it's my poorly positioning of the extractor nozzle. One thing it did do however, was to extract the fine dust from sanding. - so not a complete waste of time. I'd recommend something face mounted in addition to what ever you choose to use on the lathe. Lots of options for that, ranging from a 99p dust mask, to a couple hundred for a powered respirator.
Coley

 

[sploo]

For the best advice read this first: a-guide-to-dust-extraction-by-member-siggy-7-t102025.html then make up your own mind.

Just one point on cyclone/Thien Baffles and the like, their only function is to help prevent find dust getting to the main suction machines filter and therefore delay the cleaning of same, you can not use a collection bag with them due to their function, therefore when you empty them you are exposed to the fine dust you where trying to avoid, for fine dust its far better to use a vacuum cleaner type devise with a bag and good filter, Numatic vacuums have the facility for up too four filters and an additional HEPA filter if you feel the need.

Large chips are a totally different matter, read the above link and you will then be in a position to make up your own mind.

Mike

Delayed cleaning with a separator is a benefit, but the main purpose is to allow the use of a fine filter (that will trap the really dangerous fine dust particles). Hitting such a filter with larger material will quickly destroy it. A tougher, coarser, filter will withstand impacts, but is usually terrible for fine filtering; until it gets caked with dust, at which point the suction of the system has dropped such that it's not actually capturing the dust at source anyway.

 

[sploo]

Do you think you may ever add to your tool arsenal ? Perhaps adding a planer thicknesser, router or a table saw ?
If that were the case, I'd be tempted to have 2 different extractors. For the hand tools, a hoover type extractor, the larger the hose on it the better.
For your lathe, bandsaw and any other machinery, something with a 4 inch hose might be more suitable.
When I first started playing on the lathe, I was determined I wanted to do it cleanly. The ultimate goal being to have no chips or dust flying anywhere. Even connected up to a humongous extractor I was never completely happy with the extraction. Perhaps it's my poorly positioning of the extractor nozzle. One thing it did do however, was to extract the fine dust from sanding. - so not a complete waste of time. I'd recommend something face mounted in addition to what ever you choose to use on the lathe. Lots of options for that, ranging from a 99p dust mask, to a couple hundred for a powered respirator.
Coley

I've never had much success with capturing material from a lathe; big chips, lots of energy, flying in lots of directions. I have used a shop vac taped to a gouge when turning some MDF, and that worked reasonably well, but good general extraction when turning would be really hard to achieve.

 

[MikeJhn]

For the best advice read this first: a-guide-to-dust-extraction-by-member-siggy-7-t102025.html then make up your own mind.

Just one point on cyclone/Thien Baffles and the like, their only function is to help prevent find dust getting to the main suction machines filter and therefore delay the cleaning of same, you can not use a collection bag with them due to their function, therefore when you empty them you are exposed to the fine dust you where trying to avoid, for fine dust its far better to use a vacuum cleaner type devise with a bag and good filter, Numatic vacuums have the facility for up too four filters and an additional HEPA filter if you feel the need.

Large chips are a totally different matter, read the above link and you will then be in a position to make up your own mind.

Mike

Delayed cleaning with a separator is a benefit, but the main purpose is to allow the use of a fine filter (that will trap the really dangerous fine dust particles). Hitting such a filter with larger material will quickly destroy it. A tougher, coarser, filter will withstand impacts, but is usually terrible for fine filtering; until it gets caked with dust, at which point the suction of the system has dropped such that it's not actually capturing the dust at source anyway.

With due respect I don't have any machines that are capable of producing large chips and fine dust at the same time, collection of these are the functions of two different extraction regimes, using a separator which you can not use a bag in will concentrate that dust into a bin that you have to empty with the resulting exposure to that fine dust whilst tipping it into something, meanwhile even any fine filter has to be cleaned at some point.

Mike

 

[woodbloke65]

After some more advise, whats the best sort of dust extraction for a small hobbies workshop, need it for my lathe, bandsaw and belt sander. Such a minefield !

Thanks

David

Without wishing to promote Axminster products, this four part series of posts is something that I wrote recently as we're always being asked this sort of question. Ax. extractors have of course been mentioned but there are plenty of other products out there that would suit. The idea of this series of posts was to give the reader an idea of what to do to set up a basic system in a hobbyist workshop without going into too much technical detail, which can be off -putting. The whole area can be very difficult to understand and this was a way of making the whole process of setting up a dx system a little more straight forward - Rob

http://knowledge.axminster.co.uk/dust-e ... cs-part-1/

 

[sploo]

With due respect I don't have any machines that are capable of producing large chips and fine dust at the same time, collection of these are the functions of two different extraction regimes, using a separator which you can not use a bag in will concentrate that dust into a bin that you have to empty with the resulting exposure to that fine dust whilst tipping it into something, meanwhile even any fine filter has to be cleaned at some point.

Mike

Just about any piece of machinery will produce a range of sizes, including some fine dust (heck, even a hand plane will make some dust - despite claims from some that they're dust free). Sure, a table saw isn't going to produce chips the size of a planer, but when I say "chips" I mean pretty much anything that's visible (and will likely be reasonably well trapped by even a poor filter). It's the really tiny stuff that does the damage to your lungs, and that's where the separators can help.

In terms of having to clean filters; absolutely, though from reports I've seen of the really good cyclone systems, the amount of dust that hits the filter is staggeringly small. Sadly I've never been able to buy or build one as the designs all appear to require taller ceiling heights than I have.

I guess an outside placement would solve that problem, as well as dust when emptying the bin.

 

[sploo]

After some more advise, whats the best sort of dust extraction for a small hobbies workshop, need it for my lathe, bandsaw and belt sander. Such a minefield !

Thanks

David

Without wishing to promote Axminster products, this four part series of posts is something that I wrote recently as we're always being asked this sort of question. Ax. extractors have of course been mentioned but there are plenty of other products out there that would suit. The idea of this series of posts was to give the reader an idea of what to do to set up a basic system in a hobbyist workshop without going into too much technical detail, which can be off -putting. The whole area can be very difficult to understand and this was a way of making the whole process of setting up a dx system a little more straight forward - Rob

http://knowledge.axminster.co.uk/dust-e ... cs-part-1/

Only had time to read part 1, but that's a good article, and Pentz's site is highly recommend (if heavy going). I was able to vent outside at my previous garage (http://spikyfish.com/DustExtraction/) but having just moved into a new place I won't be able to do that, and haven't had time yet to work out a solution.

 

[MikeJhn]

The requirements for a lathe as opposed to a belt sander and to a certain extent a band saw are so different not one machine will do it all, the chip extraction from a lathe according to what is being machined (ignoring MDF) requires a chip extractor defined as a High Volume Low Pressure (HVLP) large fan sucking through a typically 100mm dia pipe: http://www.axminster.co.uk/axminster-ho ... tor-501263.

Dust extraction as from a belt sander, hand sanders and the like need a Low Volume High Pressure (LVHP) vacuum type machine: http://www.axminster.co.uk/machinery/du ... extractors these are capable of taking multiple filters and bag collectors to minimise the exposure to harmful fine dust.

Its a shame that Axminster have combined these two very different extraction requirements under the heading "Dust Extractors" in the main heading of "Machinery" and have not differentiated between the Dust and Chip Extractors until after you have entered the "Dust Extractors" heading, this is bound to cause confusion to a beginner on what is required, hence the constant question being asked of what is needed.

Mike

 

[MikeJhn]

As I said earlier, all a separator does is move the fine harmful dust to a bin instead of being contained in a filter bag, the more fine dust in a filter bag the more efficient it becomes in blocking the path of fine dust to the open air and your lungs, venting to the outside with an extractor is fine as long as your garden/neighbours can stand the noise and dust being discharged into that area, and you don't mind exhausting your hard earned heating on a cold day, with these cyclone type interceptors you still have the problem of emptying the bin of all the fine dust you where originally trying to avoid, this seems to be ignored by all who support their use, I got rid of mine purely because of the concentration of fine dust in a very small area, it made a nonsense of using one when I had to use a full face helmet to responsibly empty it.

Mike

 

[woodbloke65]

... cyclone type interceptors you still have the problem of emptying the bin of all the fine dust you where originally trying to avoid, this seems to be ignored by all who support their use, I got rid of mine purely because of the concentration of fine dust in a very small area, it made a nonsense of using one when I had to use a full face helmet to responsibly empty it.

Mike

I would agree. The chippings and dust debris does accumulate in the collector, but my 220l water butt is so large it doesn't need to be emptied all that often. It's been in use now for a couple of months and is only about 60% full. The machinery is used on pretty regular basis and the only thing I have to do is to shake out the Camvac cloth filter each Sunday morning by banging it against a tree in the garden (wearing a dust mast as well). I guess the butt will need to be emptied some time towards the end of May when I'll have to don a full face respirator but it's not really too much of a chore - Rob

 

[sploo]

As I said earlier, all a separator does is move the fine harmful dust to a bin instead of being contained in a filter bag, the more fine dust in a filter bag the more efficient it becomes in blocking the path of fine dust to the open air and your lungs
Mike

Typing on a phone whilst looking after a toddler, so can't go into that much detail; but that's the exact opposite of the intention of a good separator. The idea is to get the larger stuff into the bin, and only the finest dust (low mass) gets pulled off the walls and through the impeller and filters. By doing this, high quality filters can be used (without damaging them), and the tiny volume of dust means that airflow isn't lost due to caked filters.

As soon as you start to clog a filter it'll kill airflow; so, sure, less will pass through, but then the system won't collect properly at source - which kinda defeats the point.

Bill Pentz's site is a really good read on this subject, albeit very wordy.

 

[sploo]

Re emptying a bin: surely you have to do that with all extractors though? It is possible to use a bag with a cyclone, but it usually needs a support inside the bin, or a vacuum line to suck the bag to the bin wall. I use a Onieda mini cyclone (Ultimate Dust Deputy, IRC) with a Festool CTL vac for LVHP extraction, and it does just that (vac line to the bin).

Plus, suiting up to occasionally safely change a bin is worth it for having good (safe) extraction on a day to day basis, surely?

 

[MikeJhn]

Removing a support from inside a bin defeats the object of trying to keep the dust contained in a bag, on the majority of reports concerning cyclone's the user's report how little dust gets to the filter's.

Quoting your own post "In terms of having to clean filters; absolutely, though from reports I've seen of the really good cyclone systems, the amount of dust that hits the filter is staggeringly small. Sadly I've never been able to buy or build one as the designs all appear to require taller ceiling heights than I have."

The fine dust is nearly always in the bin, that is why I dismantled my cyclone the amount of dust in the collection bin caused a cloud of dust when emptying the (to large) receptacle into a bag for disposal, which rather defeated the object of having one in the first place, with a chip extractor the waste sack is just removed prior to becoming full by closing the top, hardly any dust/chips escaping the sack, with a Numatic type dust extractor (four filters) and its enclosed bag collector, the plastic seal on the bag does not allow much dust to escape, look at any picture of a separator bin and you will see dust over the outside: http://knowledge.axminster.co.uk/wp-con ... 7/02/1.jpg this is exactly the fine dust we are trying to avoid, probably attracted to the bin by static.

Mike

 

[sploo]

Removing a support from inside a bin defeats the object of trying to keep the dust contained in a bag, on the majority of reports concerning cyclone's the user's report how little dust gets to the filter's.

Quoting your own post "In terms of having to clean filters; absolutely, though from reports I've seen of the really good cyclone systems, the amount of dust that hits the filter is staggeringly small. Sadly I've never been able to buy or build one as the designs all appear to require taller ceiling heights than I have."

The fine dust is nearly always in the bin, that is why I dismantled my cyclone the amount of dust in the collection bin caused a cloud of dust when emptying the (to large) receptacle into a bag for disposal, which rather defeated the object of having one in the first place, with a chip extractor the waste sack is just removed prior to becoming full by closing the top, hardly any dust/chips escaping the sack, with a Numatic type dust extractor (four filters) and its enclosed bag collector, the plastic seal on the bag does not allow much dust to escape, look at any picture of a separator bin and you will see dust over the outside: http://knowledge.axminster.co.uk/wp-con ... 7/02/1.jpg this is exactly the fine dust we are trying to avoid, probably attracted to the bin by static.

Mike

By "fine" (in the context of cyclonic separation) I mean down at the level that's considered particularly dangerous to lung tissue. Generally this means "stuff you can't see", or to put some figures on it: 10 micron and under. A human hair is about 100 microns thick, and under about 20 microns is usually considered not to be visible under normal conditions.

Will you have lots of powder dust in a cyclone bin? Absolutely - but that's the (relatively) heavy stuff that just cakes up filters (not that I'd particularly want a lung-full of it though). That means the cyclone is doing its job, and ensuring only the dangerous stuff is hitting a (hopefully) high quality filter.

In terms of dust causing problems when changing a bin/drum - that seems to be more a product design issue than a specific problem with the technology. The Oneida shop vac cyclone I use can take bags; though obviously the whole thing can be easily wheeled outside for changes. I don't know if their larger (fixed) systems have similar ways of doing a clean bag change, but I can't specifically think of why it wouldn't be possible to have a drawstring type bag in a cyclone bin, and pull that closed after lifting the lid just a little. Given how paranoid Pentz is about dust I'm surprised that I don't recall him mentioning safety issues when emptying a cyclone - though given the amount of text on his site it may well be that I've just not spotted it.

Out of interest: what's the brand of cyclone you're using?

 

[MikeJhn]

I don't use a cyclone anymore, but I did have a Pentz designed cyclone, I still have the Numatic cyclone adaptor that I also don't use anymore with dust making machines, bur rely on the four filter system inside the vacuum, the cut open Hepa filter bag is disposed of whenever the unit is opened for disposing of the collecting bag, my Axminster chip collector: http://www.axminster.co.uk/axminster-ho ... eal-717658 with fine dust filter, although not fine enough is a very effective cyclone itself the collected debris spinning around inside the bag is quite fascinating and does keep a lot of debris away from the filter, I also wear a Trend Airshield Pro much to the amusement of my OH this protects up to APF 20/FFP3 which is about as reasonable as you can get without going to very expensive extremes.

The problem is you can't use a bag inside a bin type cyclone without a supporting cage of some kind, when emptying, either the cage would have to be thrown out with the draw string bag, or the cage pulled out of the bag and expose the operative to the plume of dust that would ensue which all defeats the object of the cyclone, unless you can as you say take the whole thing outside wear appropriate protection and expose your neighbourhood instead.

Mike

 

[MikeK]

The problem is you can't use a bag inside a bin type cyclone without a supporting cage of some kind, when emptying, either the cage would have to be thrown out with the draw string bag, or the cage pulled out of the bag and expose the operative to the plume of dust that would ensue which all defeats the object of the cyclone, unless you can as you say take the whole thing outside wear appropriate protection and expose your neighbourhood instead.

I remember seeing a method where a small vacuum line was added to the drum holding the bag. The eliminated the pressure differential and prevented the bag from being sucked up into the cyclone. Apparently, it worked well and if I can find the link, I'll post it here.