Baffle Mod

[Bill_In_Alabama]

Have you considered making a baffle slightly larger than the diameter of the container, cutting it along the radius just behind the input port so you could create a ramp? I think 1/4" hard board is flexible enough to permit it to fold in a little underneath itself.  I just ordered my dust ports from Rockler and now I need to make a circle jig for my router.  I couldn't find masonite with two smooth sides at HD.  I haven't tried Lowes yet.  Where did you find a source or

[dbhost]

What are the chances you could draw what you are talking about up and posting it? I am having trouble visualizing what you are trying to do... Then again I can be kind of thick sometimes too...

I don't think hardboard is absolutely neccesary, I used 1/2" sanded white oak ply for my separator...

[Bill_In_Alabama]

I'm not proficient at using drawing packages, so I made a model out of a piece of cardboard.  The first picture is intended to show the baffle unchanged and the second picture shows the mod.  My camera had some trouble focusing at such a short distance, but I think the pictures are clear enough to see what I was talking about.  It turns out that it made the baffle a cone, but if the diameter isn't increased and  it isn't folded under, it would merely drop the edge in front of the input.  I also guessed at the angles.

http://picasaweb.google.com/wjburl/Baffle#

[dbhost]

Well, an interesting idea... Have you tried this yet? I would think it may lead to more scrubbing of the material down in the bottom of the can, but I could be wrong...

[Bill_In_Alabama]

I have not tried it.  I haven't built my separator yet.  I have the Rockler dust ports on order. I haven't bought the other materials needed and I still have to make a circle jig for my router.  I would like to make the version proposed before I try any mods.  It looks like it'll probably be a week before I can even begin construction.  I was watching a video on Stu's Shed and he built a system that didn't even have a baffle.  He acknowledge that it wasn't a cyclone separator and it still did a pretty good job. Another question - does the corrugated side on a galvanized garbage perform any differently than a barrel with smooth sides?

[dbhost]

Good question. Knowing what I do about fluid, and aerodynamics, I would have to say yes, there IS an impact to performance. As I understand Phil's idea, the incoming air basically swirls around the outside of the can, drops its load and then moves up to the output tube. Any interference with the airflow will effectively drop the CFM of the total system.

As the air spins around the outside of the can, it slows down, the load can then having less air speed to support it, be dropped into the can. The bumps / ridges on a trash can I would think would increase the resistance on the air flow, and thus slow it down more, increasing the "drop factor" of the dust laden air.

Of course I could be all wet and completely miss the point of Phil's design. I am no engineer after all.