James
I used that SIP as the basis of my dust collection, sucks like a good 'un. Below is guts of a post I made a few days back to somebody with a similar question...
"My workshop is roughly 3m x 5m so overall a little smaller than yours. I have one of these (I paid a fair bit less than this buying it from CostCo so I'd advise shopping around)
https://www.sipuk.co.uk/sip-01954-dust-collector.html
Which is wall mounted...
...and spiral ducted to my main machines...
Before it was wall mounted I did move it around, but to be honest in a small space this actually proved to be a PITA as there was never the space to put it somewhere that was not in my way. Breaking the machine down also makes it much easier to insert a cyclone into the system, which frankly is IMHO a no brainer. For a 3HP extractor I was advised to go with a bigger cyclone.
In my experience when it comes to extraction bigger is better. The larger the amount of air moved the more efficient the extraction will be, so go for the machine with the best possible airflow. Then use the biggest ducting you can (whether you plumb it in or not), so if you go for the second Axy machine you link to dump the splitter that reduces it from 125mm to 100mm and use 125mm pipe or ducting.
Beware of any claims about airflow and filter efficiency. Manufacturers will test in optimal conditions (I don't blame them for that), so I have heard people say they do not get anything close to the quoted airflow. But I strongly suspect they will, for example, have tested with 125mm and not used the 100mm splitter and will be using the shortest possible lengths of flexible ducting as the corrugated interior interfers with the efficiency of the airflow. On filtration test any assertions about "filtering down to" a particular size of particle, what you want to know is what percentage of a particular size particle will be filtered out, not just the smallest particle that can theoretically be captured.
The top bag on the SiP model I have is useless so I made my own using HEPA filters from an purifier. I used the ones used by this guy (jump to 4:40 if you just want to see the point on filters).
https://m.youtube.com/watch?v=CrAtUVo-47g
He uses two on his 3HP extractor and seems happy, but I was worried about reduced suck so I made a bigger filter box (the big thing on the left in my first picture, only the top half mind as I put some moveable shelves under it) with four of them pre filtered with a double layer of 20mm G4 rated filter media in front of each HEPA filter. I have found no noticeable reduction in suck when hooked up to the filter box, though in fairness I do not have the equipment to measure it scientifically.
Finally, if you do have it in a fixed spot set it up to be remote operated that way you can use it everytime, rather than not bothering because it is to troublesome to keep going over to switch it on."
Hope that helps.
Terry.
