J. Phil Thien's Projects

 I am not aiming for perfection . My main interest is balsa dust since that is what I generate the most . Those vertical strips seem to help .

Quote from: retired2 on March 15, 2015, 04:08:07 PM

Quote from: sportflyer on March 15, 2015, 02:43:44 PM

Quote from: BernardNaish on March 15, 2015, 12:43:05 PM
A useful experiment. It looks as though you are on to something here. I wonder what would happen if yours strips were angled down towards the slot? Again what would happen if the strips were thicker? Sorry - my mind is racing ahead of my concern for your work load.

"angled down towards the slot "  Do you mean for example angled at  70 degrees  in the direction of air flow instead of my 90 degrees or you mean thick at the top and thinner at the bottom or both.

I'm pretty sure he means angled the way I described it in my earlier post in thiis thread.  In that post I suggested the ribs be angled in the direction of the airflow.  So instead of your ribs being vertical they would be rotated, say 30 degrees.  Now as I pointed out in my post that creates a real fabrication challenge because they can't be flat because they need to follow the curvature of the drum.

Yeah , that would be difficult to machine  properly due to changing curvature :( .  I wonder whether it necessary to follow the drum surface that accurately . Perhaps a little slop is OK ? I will see how much slop there is . Also now we are deflecting some of the sir directly into the slot and could possibly  churn up the stuff below the baffle .

Quote from: BernardNaish on March 15, 2015, 12:43:05 PM
A useful experiment. It looks as though you are on to something here. I wonder what would happen if yours strips were angled down towards the slot? Again what would happen if the strips were thicker? Sorry - my mind is racing ahead of my concern for your work load.

"angled down towards the slot "  Do you mean for example angled at  70 degrees  in the direction of air flow instead of my 90 degrees or you mean thick at the top and thinner at the bottom or both.

Jnug , adding some wood strips  around the drop zone seem to help with fine dust separation :  see http://www.jpthien.com/smf/index.php?topic=1167.15

As an experiment ,  I  temporarily stuck some 1/4 in  thick ply strips on my pail wall  in the drop zone  with double sided tape .  The length of the strips bridge the top of the cover to the baffle and approx 3/4 inch wide.   I am happy to observe that it improved the fine dust collection tremendously.  It seems that these "turbulators" work very well. See attachment .

Here are the pictures.

I built the separator and tried it out . I believe it works very well except for some very fine dust which still goes through to the shop vac . I am not sure how deep the output tube has to be relative to the   input elbow. Right now I have it about 50 % of the elbow opening . Could this be too far in so there is some amount direct feeding from input to output ?  Perhaps a shield  around the input elbow would help?  Any advise ?

This morning ,  I modified the inlet elbow so i'ts closer to the top.  The elbow, inlet and outlet pipes have a snug fit to their resp holes because I hand routed a small rabbet so the pipes sit about 1/4 inch below the surface. I then glued them down with E6000.  The outlet pipe is just a snug fit so I can adjust the spacing of the pipe from the drop platform.  See pictures

The original Thein photo show the elbow exactly at the transition point between the end of the drop zone and the beginning of the  platform so there is actually less dust travel distance than the 120 degrees.  I would have thought that the position of the elbow is such that the elbow output is just slightly pass the end of the 240 degree drop zone so the input dust  has maximum travel before the start of the drop zone.

I will try 2 inch dia pipes because it's more suitable for a direct hook up to the  shopvac . 

I would like to build a Separator based on a 5 gallon pail .  With only approx 12 inches across the top ,   a 4 inch elbow is just too large  with almost no space between it and the output tube.  I would like to reduce the input elbow to 3 inches and use a shortened 2.25 inch Shop vac extension tube as the output . Would this cause serious performance problems? Too much velocity ?  Thanks

Hi everyone. I just joined . Wood working is not my primary hobby. My main hobby is building and flying radio control model airplanes .My secondary hobby is Audio .   I do use various wood working tools to build them especially the larger ones.  I have several questions re the Dust separator but I cant seem to find the button to post a new topic. Tks