I had the idea to make a swing arm to make dust collection easier. I first thought about using some scrap metal I have to weld together a stand and hinged arm. Went to get the metal and noticed I had some 1/2" gas pipe and connections that would work perfect. 20 minutes later working arm. It works great but I see a couple areas for improvement like getting rid of othe 90 angle on the connection point and adding a dust separator.

Very cool idea! Nice work.

I would suggest that you try to remove the flex duct from the inlet collar to the the bracket mounted part on the wall and replace it with hard smooth duct. Then put a hard 90 degree elbow and a very short section of flex (1-2FT) to allow the arm to swing 180 degrees or whatever range you need. From that short 1-2ft of flex hook more hard smooth duct to the next elbow pointing down. Then use the flex you want going down to the piece of equipment/dust source.

The least amount of flex will get you by far the best suction out of the system. I didn't sleep in a Holiday Inn last night but I have been designing dust collection and chemical filtration systems for 28 years for a living...just trying to help you get the best performance possible out of your fan package.

Good luck and feel free to ask me any questions if you want any help/ideas.