Thread: Dust Catching for a Riaial Arm Drop Saw.

Originally Posted by Mini

I'll have a go at this. Build a box with a plenum behind the main box, basically a small are at the back of the box and at the bottom. The inner rear wall does not go to the bottom of the box, the gap being equal to the square area of the dust extractor pipe. If using a 150mm pipe then the area of that pipe needs to be the same as the gap and the pipe is attached to the plenum. Fire up the extractor and all the air rushes through the gap so any dust that is fired into the box falls to the gap and is drawn through it and into the extractor. The problem is most extractors just don't pull enough air and that is the important bit. BTW the back wall slopes away from the top box to the bottom so the dust hits it at an angle. The first link shows the idea in action

YouTube - Miter saw dust collection hood in action

This one shows what a decent air flow does, notice how the dust actually changes direction due to the enormous air flow.

YouTube - Chop Saw Dust Collection with a Clearvue Cyclone

In the end if you want to build a good collector for a mitre saw then it needs strong air flow. This is the main reason so many hoods just do not function as they should. It has to be the hardest tool in the shed to collect dust from.

Good Stuff!!!. But the 100mm hole is installed in my collection box and with the dusty attached the problem is rough but successful. A deflecter will be fitted to the top for when the saw is 'out', and from observation that should be good enough.

I reckon that many that read this thread will benefit from all your knowledge and suggestions.

A big thank you blokes
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