I recently made the miter saw stand from Popular Woodworking.
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have been wrestling with dust collection for a saw on a movable stand. Inspired by the website of Barry Burke:
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(scroll to the bottom of the webpage)
I have completed my version of his dust collector. It works quite well. It is large (40" across) to accomodate the swing of the saw from left to right. I have posted pictures on alt.binaries.pictures.woodworking