I have recently bought myself a Flux Beamo laser cutter and am now in the process of setting up fume extraction for it to vent outside. The laser unit has a built in fan of which I haven’t been able to find the specs but it’s fairly powerful. It also comes with a 2 meter length of 100mm diameter ducting which attaches to the laser via a hose clamp. My plan is to use about 400mm of that ducting to go from the laser cutter that is sitting on a table to a section of 100mm PVC pipe about 1 meter long, which will sit again the wall and go up to a 90° bend and then though the wall to the outside. I now have a couple of questions. The first is that I’ve seen small fans on AliExpress that are designed to fit into 100mm pipe: https://a.aliexpress.com/_mMqOjk9
They claim to be 12 watt and I thought that I could add one in between the ducting and PVC pipe to increase extraction, but by doing this am I actually increasing air flow even if it is less powerful than the laser fan before it? I don’t want to restrict the flow of the existing fan. My second question is that I will need to put some type of cover over the hole on the outside to stop rain coming in, however I’m not sure wether to use one with angled slats that are always open or one the has tilting slats that only open when the fan is pushing? I feel like the second one has more resistance but I’m not sure to what degree.