Shropshire Association of Woodturners


How many members use a dust extractor with a filter bag on top and a collection bag underneath, and how often do you clean the filter bag?

What is more important, did you realise that it had to be cleaned on a regular basis to ensure that the extractor works efficiently. In order to work, the extractor has to be able to draw in an enormous amount of air which contains the dust, extract the dust by centrifugal force then get rid of this air via the large bag filter which removes any minute particles of dust that are left. The air is blown out of the bag with such velocity that these dust particles are forced together and stick  like glue to the inside of it. One would think that when the extractor  was turned off, and the bag deflates, this dust would fall into the collection bag at the bottom along with all of the other larger particles but in fact most of it stays in the bag.

The result is that less and less air can be forced out through the bag so the suction effect gets less and less also. I recently cleaned the  filter on my machine and a whole bucket full of flour like dust was  taken out. This amount had obviously been clinging to the sides of the bag even when it was hanging deflated. The result was immediately  noticeable, the suction effect drastically improved. 

Try yours by simply unhooking the bag, letting it sink into the collection bag then giving it a good shake.  Wear a mask though as it creates a lot of very fine dust in the surrounding air.  Check the suction before and after cleaning the filter bag, you will be surprised.

 Fred Harris.

Woodturning inevitably creates dust.  This can be a nuisance but more importantly it can be a health hazard.  Some information about this is available here though it primarily applies to building works.