How small is small ? 10 inch or less ??

[nachtwacht]

Hello,

I have done some searching on the forum for small Thien separators but it appears that when people talk about small here they still have very hefty machines in mind :)

Therefore I thought, lets ask the forum if they think what I have in mind is in any way possible.

I am thinking of building a separator that would have a maximum diameter of 10 inch. The idea is to make it with a side inlet (I mean the port where the dust is comming in) and I would prefer to have it 4 to 5 inch high.

The dust colector I would want to hook up to it would be a normal dust collector used for powertools. (wich is what I want to use the separator for) It would have a maximum airflow of 3900l/min. The vacuum cleaner would come with a roughly 1 inch hose so my inlet and outlet would be something close to that size.

I am personaly wondering if this is in any way possible... I can imagine that the "chamber" would be to small and dust would be sucked to the vacuum cleaner... then again, if it works in bigger sizes with heavier machines, why would it not work with a smaller size and a smaller machine... Unfortunatly I just don't have the wisdom to come up with the right answers myself.

So anyone that would be able to shed some light in the darkness, thanks in advance !

[phil (admin)]

This is one of those cases where all I can say is that you will have to try it.

For those sizes, of course, you have to use a vac, not a DC.

One of the weaknesses of my design is the possibility of bypass.  Because the bottom of the outlet is nearly aligned with the top of the inlet, it is possible for incoming debris to exit the outlet without entering rotation.  This is called bypass.

This is less likely on a conventional cyclone, as the outlet tube's bottom is substantially below the bottom of the inlet.  Incoming debris is more likely to enter rotation and not bypass.

One of the reasons more debris doesn't bypass in my design is that the air is already revolving.  There really isn't a straight shot to the outlet tube, the debris coming in has to pierce the revolving air mass in order to get to the outlet tube.

This is one of those cases where you're going to have to build one and see if it suits you, I'm afraid.

[nachtwacht]

Thanks for the answer. The air in your original desig revolves because a DC makes it revolve I guess ?


I was suprised to not find any <10 inch separators on your website especialy since the ready build cyclones you find (dust deputy etc), that are used for vacuum cleaners all are even smaller than the 10 inch that I have in mind. Maybe because of the height they have (wich is what I want to avoid) they get the revolving air in those cyclones ?


I guess I will indeed just have to give it a go because I want to avaid the hight of a cyclone and want to build everyting into a "smalish" box.

If it does or does not work out, I will be sure to post the results.

greetings

[Rick T]

nachtwacht, I use a DD  attached to my shop vac and it works well. I've had the DD for @ 5 years now, but if I didn't have it I would certainly try to build a "top hat" version on a large painter's pail. My setup is a 6 (peak) HP Rigid shop vac equipped with an internal pleated HEPA filter. I have a 1 1/2" dia hose feeding the DD and suction is provided via 2 1/4" ? dia hose from the vac. I get virtually no blow-by into the vac provided I remember to empty the collection pail. I use the vac for general clean-up as well as my sanders, router table and  oscillating spindle sander so it gets a fair amount of fine dust. I intend to get a smaller dia hose.. @ 1" dia for use with my hand-held tools because the 1 1/2" hose is too cumbersome and heavy.