Dust is destined to be with metal. With plastic, a static charge is
developed and can cause explosions. Some run a bare copper wire down
the pipe and ground the wire to bleed off the charge.

Martin

On 9/16/2013 7:44 AM, Joe wrote:
I noticed some black flexible ribbed hose used in a dust collection accessories ad at http://www.rockler.com/product.cfm?page=11312&rrt=1 .

I tried some stuff that looks like it that is sold as drainage hose. It is similar to http://www.lowes.com/pd_259812-62059...nch&facetInfo= or http://www.lowes.com/pd_24136-124-04...nch&facetInfo= .

When used on a dust collector, the moving air across the ribs makes it sound like there's a steamboat whistle in the shop.

I've tried different lengths and flows to get away from the resonant frequency with no luck. It only changes pitch.

Has anyone had any luck with this stuff? The price on the clear stuff is outrageous and the wire makes it harder to work with. The black stuff curves easily and neither collapses nor shrinks under vacuum.