Those Vortex tubes are cool, hehe! I had no idea what one was until you mentioned it, this youtube video helped too. I suppose for repeatability I could do a circle, diamond, square test and perhaps I can get an idea of resolution by measuring the smallest arc I can accurately make.
Air safety is very important to me. I will be using the machine inside the house with my wife and daughter around and I would be devastated if I made any of us sick. I understand wood can release spores, viruses, and general respiratory irritants in the very fine dust cnc machining produces. I am hoping to reduce the risk from wood by using a shop vac with a hepa filter (is this enough?). I looked up an msds for Renshape and couldn’t find much info about RenShape460_MSDS.pdf (955.6 KB). I saw the discussion regarding air quality in relation to milling FR4 pcb boards and am looking into a festool vacuum. Anyone have any opinions on the smaller model of festool vacuums such as the CT MINI HEPA or MIDI? I like the compact size of MINI and MIDI vacuum and I don’t think I would end up emptying it out that often, especially if I had a cyclone upstream of the vacuum. The other vacuums seem too large (I live in a smallish apartment).
I like the Nomad because it seems very refined for the money. It looks nice too 
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