I have a dust collector that I use to collect dust and chips from most of my woodworking tools including my table saw, jointer, planer, band saw, router table and all of my sanders. Lately I have been clamping the 4" collector hose to the table of my scroll saw. So I decided to do something more permanently. I used two 2 1/2" hoses with fitting to mount above and below the table:
http://www.woodcraft.com/Product/2021187/28973/212-Dust-Source-Rigid-Flex-Set.aspx. I used zip ties to mount the top hose to the upper arm and the the 4" hose to the leg of the stand. The hose does not add much weight to the upper arm.
I haven't given it a thorough workout yet, but it seams to do very well so far!