Another ***** question: dust extractors in series?

[Deadeye]

This woodworking thing is fun, but hard if you're teaching yourself.

I built a cyclone - which works really well. It's attached to an 850m3/hr extractor (basic Axminster one).
Question 1. I have positioned the extractor downstream of the cyclone, so that it handles clean air. Is there a reason not to do this (normally the chips and dust go through the machine and into a bag)?
Question 2. It handles bandsaw, tablesaw and router table really well (yes, I went shopping). It finds the planer/thicknesser harder to keep up with. By that I mean some shavings end up on the floor; blockages haven't been a problem. I use blast gates at each machine. I have been offered a second, similar spec, extractor. Could I add it in series, perhaps close to the P/thicknesser? Or is that a daft idea and I need to buy a new one with double the airflow?

For what it's worth, it's all 100mm, except the router table steps down to 60mm.

thanks

 

[PAC1]

You need to match the extractor to the machine’s stated requirement. It is unlikely that a Planer/thicknesser only requires 850m3/hr extraction. Most require about 3 to 4 times that level of extraction.
As for the rest read Siggy7’s extraction thread.

 

[MattRoberts]

Pointless having a cyclone after the extractor - the purpose of a cyclone is to capture the chips before they get to your extractor, as it's easier to change the cyclone bin than it is to change the extractor bag / clean the filter.

As for running then in series, I read somewhere that you can do this and see a small improvement, but not as much as just upgrading the extractor you have to a 2hp or more

 

[siggy_7]

You've positioned the cyclone correctly, I've never seen someone with a cyclone after the extractor.

If you're struggling for airflow, my advice would be to sell on your current extractor and upgrade to a single bigger unit. I would have thought having extractors in parallel rather than series would give better performance if you wanted to add a second unit instead, but you would need to take care to balance performance of the two (e.g. two identical units with a similar length of inlet hose to a common y-piece).

 

[MattRoberts]

You've positioned the cyclone correctly, I've never seen someone with a cyclone after the extractor.

If you're struggling for airflow, my advice would be to sell on your current extractor and upgrade to a single bigger unit. I would have thought having extractors in parallel rather than series would give better performance if you wanted to add a second unit instead, but you would need to take care to balance performance of the two (e.g. two identical units with a similar length of inlet hose to a common y-piece).

Having extractors in parallel means that one impeller will starve the other