6 inch design

[alan m]

hi there.
great forum and great product.
i started down the metal cyclone route but hit a dead end  looking for someone trust worthy and good enough to weld it all together. \i had hears about this design and passed it off thinking it wasnt any good and started the cyclone. then when i stoped the cyclone i said why not try the baffel idea . so i did. i used a small barrel with a sealed lid adn suspended a baffel from it.
i couldnt follow the plans on that one as it wouldnt work with thwe barrel . it works great with my festool ct22 extractor, even thow it isnt built properly to scale etc.
anyway now i am back needing a big seperater for my workshop  system that i am abou to put in.
i was hoping to use a 80 gallon (not a us gallon but british or eu ) or a wheely bin (not sure of the us design but over here they are a square cross section tapering out as they go up  and have wheels and a flip up lid).
i am not sure if the wheelybin will hold up to the pressure   or not (on my smaller one, the barrel gets sucked in a bit so i had to bolt pieces of wood inide to stop the plastic bending in.
i see that the normal design is for a 4 "pipe system. should i adjust the size to suite the 6" pipes.should th eoverall radius of the baffel be made larger to  allow for the increase in inlet size.
i was thinking of making it a horezontal inlet design.
i am going to upgrade the power scourse by buying anouther chip colector(with the impeller houing seperate from the ring for the bag etc) and using the whole housing  and motor  and bolting that above the baffel. the online store selling the dc unit says it will moove 3900 m3 an hour(over 2200cfm if google is right). given that those numbers are inflated  at times  a bit. do you think that is too much for the  baffel   . will the high cfm suck the dust up before it gets to drop down through the slot

any advice would be aprieciated
thanks alan

[alan m]

i am thinking of making the top hat seperater part 10-12 " high so that there is more room to swirl round and seperate the fine dust out.
is there any advantage to doing this. there is a lot more work to cut out all the extra layers if it doesnt add a lot to the seperation.

[Bulldog8]

Alan, you are right. Phil discussed that in a different thread. I haven't seen pictures of anyone using the idea yet, but it's on my "to do" list. The concept was to use a side inlet mounted high on the chamber, with an increased chamber depth to allow the dust stream to slow more before re-entering the incoming stream. The outlet pipe would have to be lowered the normal 1/2 D, plus whatever the chamber depth increase amount was.

Steve

[alan m]

would i be right to think that the 1/2 diameter rule should be from the baffel  rather than from the top. in my case the end of the outlet tube will be 3" above the baffel.
is there a link to that threa please.

should the inlet pipe be at an angle or left square

thanks alan

[retired2]

Alan, you are right. Phil discussed that in a different thread. I haven't seen pictures of anyone using the idea yet, but it's on my "to do" list. The concept was to use a side inlet mounted high on the chamber, with an increased chamber depth to allow the dust stream to slow more before re-entering the incoming stream. The outlet pipe would have to be lowered the normal 1/2 D, plus whatever the chamber depth increase amount was.

Steve

Steve,

If I had unlimited time and money, separator chamber size is what I would be testing as the next possible upgrade.  I built my DC system to minimize SP losses, and I included a lot of separator modifications to minimize its impact, but in spite of that the separator still imposes some pretty heavy losses.

Most separator builds have their chambers sized by two external components, i.e. the inlet pipe size, and the waste drum diameter.  Coincidentally, that combination works pretty well.

My belief is that some combination of a larger chamber size, either diameter or height, will produce equally good separation but with reduced SP losses.  Obviously, a larger chamber will result in lower velocity (FPM) in the chamber, so there is some point at which the loss of centrifigal force will allow bypassing.  I think the bell mouth outlet I used will help some, but I don't think it would make a big difference.

If I were to start experimenting with a new build, I think I would increase the diameter before the height because that would slow the waste stream, but would help minimize bypassing.  A larger diameter, rather than a larger height, also allows the use of a tight tangential rectangular inlet like I used.  This introduces the waste strearm over the drop slot which I believe is the ideal.  Of course, a larger diameter introduces the issue of mating the separator to the waste drum, which is likely to be a smaller diamater.

In any case, I don't think I will be building another separator any time soon, so I won't be able to advance these ideas beyond the opinions I just expressed here.  And incidentally, I should have prefaced these remarks with what should be the obvious, my comments are for top hat designs.