Quote Originally Posted by Chris Parks View Post
I have never seen a DD that worked anywhere near properly but others may have. For a start large amounts of air flow is blocked off by the object being sanded and light dust from sanding operations floats as soon as it is created so in reality you need both an overhead hood and a DD capability and that requires serious amounts of air flow. If hand sanding Mirka do a nice unit that can be hooked up to a vacuum cleaner which does from all reports a reasonable job.
You need to use a proper downdraft table. Ours has a 48x72 table and flows 4000cfm. If there's something in the air, it came from somewhere else in the shop.

I still prefer it greatly over sanding with a vacuum.