dust and woodchip extraction.

[Ridethewave]

Having just skimmed over much of whats written about health dangers etc including Bill Pences work I now realise how important good dust extraction is.
As I am new to lathe turning(3 weeks) I turn to the far more experienced and knowledgeable on here.

So my undeveloped thoughts are:

1... Build a diy cyclone extractor that first collects all the larger and smaller particles of wood chips, and then exhausts the dust and air outside the shed(my 10 by 6 homemade wooden garden shed).
2... buy something that is good enough to keep a healthy environment within the shed.

At the moment I have a door and a greenhouse louvre window at the other end of the shed.

building something diy is always appealing as it uses the creative side of me and my ideas are these
1. to use my half horsepower lathe motor which runs two separate things(lathe + planer) to run instead lathe plus dust extractor.
2. to collect the wood chips in an easy to empty container
3. to exhaust all dust through a straight pipe into my compost heap(which is 6 feet behind the shed)

Having read the dangers of fine wood dust to health I shall of course be buying a good dust mask(over £100?)

Your thoughts and advice please

John

 

[Roland]

In addition to dust you should also think about wood flying off the lathe. I use a dust mask for a lot of woodwork, but a helmet with air supply for lathe work.

 

[sunnybob]

You have about 4 seperate problems to address.
The fine dust that floats in the air from a lathe is a REAL health risk. heavy stuff that falls straight to the floor, not so much, but still needs collecting and disposing of.

A lathe motor is NOT going to give you the power you need.

A cyclone is a method of creating extra storage so you dont have to empty the bin quite so often. It is NOT a method of improving the collection of dust, It actually robs the motor of some extraction power.

Good dust extraction just cant be done really cheaply even though its boring.
Its like buying a racing car, and spending on a big engine and loud exhausts and flash wheels, but not buying decent brakes as well because no one sees them.

Emptying the dust to outside is done a lot, but just where does the wind blow it? Straight back in your kitchen door?

 

[Ridethewave]

Thanks Roland. yes I am contemplating an air supply helmet...Seem to be a few hidden expenses to taking up turning. have so far spent as much on additions as I did on the lathe.

John

 

[Ridethewave]

You have about 4 seperate problems to address.
The fine dust that floats in the air from a lathe is a REAL health risk. heavy stuff that falls straight to the floor, not so much, but still needs collecting and disposing of.

A lathe motor is NOT going to give you the power you need.

A cyclone is a method of creating extra storage so you dont have to empty the bin quite so often. It is NOT a method of improving the collection of dust, It actually robs the motor of some extraction power.

Good dust extraction just cant be done really cheaply even though its boring.
Its like buying a racing car, and spending on a big engine and loud exhausts and flash wheels, but not buying decent brakes as well because no one sees them.

Emptying the dust to outside is done a lot, but just where does the wind blow it? Straight back in your kitchen door?

Thanks Bob.
Sincewriting the opening post I soon realised that the lathe motor would not be a good idea.
As for exhausting the dust outside, I was thinking of running the exhaust pipe to the middle of my compost heap so that :
1. the compost heap would stop the dust being blown around and
2. the compost heap would break down the dust into...compost

I was thinking that the cyclone separated the chips etc from the finer particulate matter

John

 

[sunnybob]

If you bury the hose in the compost heap, you will not get any suction at the machines. allmost all extractors rely on rapid air flow at low pressure to move the dust along.

No, the cyclone does not seperate chips from dust. All it does is allow you to have a bigger collection pot inline. Say you have a 50 litre bag or pot on your extractor. when youve collected 50 litres,you have to empty it. That can be quite quickly filled with some machines.
If you put a cyclone, and a 100 litre pot in the line, the 100 litre pot fills first, then (if you dont empty it at once) the 50 litre pot will fill. So what this means is that you only have to empty it after a 150 litres, instead of 50 litres. Cyclones are good tools, but they are NOT a magic bullet to solve all extraction problems.

 

[Inspector]

I don't want to take the thread too far off course but I see cyclones a little differently. They are to separate chips and dust so that the air exiting can either be vented out of the building or in the case of colder climates, filtered to keep the heat in the shop. A good one like the Bill Pentz design removes enough dust so that the filters aren't overwhelmed with the bigger dust and can run for some time before cleaning is needed. If their only purpose was to hold more dust then we could skip them altogether and use a bigger collector bin/bag on the DC.

John when my father was alive and turning I got a couple 16" fans from industrial gas heaters that were replaced due to the cores burning through. We put them in the wall of his shop behind and below the lathe. When both were turned on they took all the dust and shavings that came off the lathe and blew them out onto the ground outside. Make up air came in through the door at the other end of the shop. Now he was on a mountain and his place was 20 acres so didn't have to worry about annoying anybody. When the pile got big enough he would rake it up and toss some on the compost pile and the rest down the hill into the bush. It was a seasonal solution though because even as tough as he was he didn't like turning in the winter cold.

About the composting. Wood takes a lot of nitrogen to break it down. One bag of shavings to three of the lawn clippings or it takes forever to rot down.

Pete

 

[sunnybob]

I've been using a cyclone for almost 4 years now. Everything goes down into the cyclone box.
If that box gets close to being filled, then chips do move onto the main drum, but thats the only time.
I emptied mine this afternoon, got a brown bin liner bag full from the cyclone. Nothing in the main bin.

 

[Ridethewave]

It seems my thoughts about the cyclone and compostheap might not be a completely stupid idea.
I wasnt thinking of completely sufforcating the end of the exhaust hose with solid compost but with looser layers.and keeping the piile fairly loose. As for grass clippings for nitrogen I am never short of them(except in the winter)as my job is a self employed gardener. Another perk of the Job is plenty of wood for my woodburner.I currently have a massive beech tree to clear that has been lying on its side for about 6 years. and other various trees come my way.
I suspect that the cone in the cyclone is there to separate fine dust from the heavier sawdust and chippings. I have a saltwater reeftank with a skimmer which does something similar just underwater and uses bubbles lol.
An interesting discussion which I think has further to go so please...continue.

John

p.s. Next to the shed and compost heaps is a log shed where I could house a diy cyclone filter, or alternatively have a huge box under the bench.

 

[sunnybob]

I dont think you would be able to keep the hose buried at all (even loosely) without losing almost all of the throughput.

It would be possible to have the pipe above the heap, and fit a down turned elbow on the end, to just blow the dust onto the pile, and then you could mix by hand. But you need to be aware that every foot length of hose is a restriction to flow, and any joint is even more restriction. If your heap is more than 10 foot from the machine, its going to have to be a BIG machine.

As far as the cyclone , mine has been working perfectly as I described for the last several years, despite being told several times on this forum that it cant possibly. So I have nothing further to add to that discussion.

 

[Ridethewave]

thanks for all your input Bob

 

[Robbo3]

I don't use an extractor whilst turning, unless it's an extremely dust producing bit of wood, only when sanding.
Although the dust is collected in a bin with a Thien baffle it could go directly to the shop vac because of the small size & amount. The paper bag has been in the shop vac for three years & has collected very little dust.

 

[sunnybob]

Robbo,
I have a friend who does turning, I stood back a couple foot and watched him turn one day.
I could not believe the amount of fine dust I could see, coming off the wood and drifting up past his face (no mask). He had an overhead mounted air filter (one of those box things with big filter pads) but it was not on. I asked him why it was not on and he replied, "theres not enough dust".

Believe me, from where I was standing there was enough to make me want to leave his shed. He just could not see it from above. I respectfully suggest you try the same experiment, and get someone to stand back from you and tell you what they see, maybe video it.

Point to add though, in my friends case, that filter was above his head, so even if it had been on it would have still sucked the dust straight up into his face. That was 4 years ago when I started to get involved with woodwork. He now has breathing difficulties.

 

[Inspector]

Our turning club had a Symposium a couple months back in a theatre. The room was painted black and with the lights shining down on the presenter you could watch the dust rising up from the lathe at least 4 meters towards the ceiling. That drove home what has been said in the dust section of an Aussie forum. That fine dust behaves as a gas and rises to hang in the air for many hours.

Pete

 

[Ridethewave]

Great observations and info there guys..Thanks.

As for my small shed, what would you use for dust extraction,particularly for the fine breathable particles that are most dangerous?

Thanks...John

 

[Dalboy]

For the best results there are three items you need for a good dust extraction and protection.
The first is the chip removal type of extractor which most of the time will not collect straight from the lathe when turning except the dust when sanding but is still very useful in a wood shop. The second is the dust extractor the type that normally hangs from the ceiling this sucks in the small dust particles and the third is a good face mask.
When turning and you decide to finish it is no good taking the face mask off and think it is safe as it takes a little time for all the airborne dust to be collected by the extractor systems, so if you continue working in the shed keep the mask on for a while or leave the shop to allow that to happen.
I also will not do any decorating of items until the next day after cleaning the workshop from the turning session as it is a pain if dust settles on wet paint finish(this last bit depends alot on the finish being applied)

 

[sunnybob]

Lathes need more extraction than almost any other machine, because they produce all the extremes. Largish chips right down to dust so fine it cant be seen, and perversely, the harder it is to see, the more it floats and the more dangerous it is.

Its best to have a large extraction hood at the rear of the lathe, and a fresh air supply from behind you blowing the dust towards the hood. Many makes, endless home made versions, but make sure you dont let it slip by you.

Even then, WEAR A MASK! You only get one set of lungs (transplants excepted) and you really dont want to be unable to even walk without gasping for breath.

And at the end of each day, vacuum the place out. Do you have kids? would you want them wandering around kicking up clouds of harmful dust when they come to see what youre doing?
woodworking can be very hazardous if you get lazy.

 

[Suffolkboy]

I just wear a paper mask.

 

[Dalboy]

I just wear a paper mask.

It is better than nothing but do you take it off the moment you stop sanding or do you leave it on for a period until the airborne dust has settled

 

[sunnybob]

have a look at the filter rating of that paper mask.

If youre just buying cheap its most likely FFP1 which isnt much cop at all for lathe turning dust.

Check out this page. I use FFP3 in the workshop regardless of what I'm doing.

http://blog.xamax.co.uk/how-to-pick-a-d ... s-p2-vs-p3