Trying to put together a minimal dust collection system (tools to adapter to hose to adapter to dust collector) has become frustrating. Any suggestions from positive experiences would be greatly welcomed. I had thought that in a 4" system a male part would be 4" outside diameter and the female parts 4" inside diameter. Foolish me. So far I have found: 1) Oneida metal adapters generally work well with each other. though occasionally a LITTLE tight fit. Unfortunately I need the flexibility of a hose and not metal piping. 2) Woodcraft plastic adapters are not the size stated, threaded adapters thread opposite to the way needed in a plastic hose bought from Woodcraft. 3) The adapter on my Saw Stop table saw is small enough that true 4" hose adapters fall off. 4) Every hose I've bought is too small to fit any of the adapters I bought. I must be doing something terribly wrong or making some idiot assumptions. Again, would appreciate some help.