Adjustable Butterfly Vent

[RoadRunner]

I am in the process of building a router cabinet to include dust control :help:. I would like to find an adjustable vent similar to the one in the picture below (I know they are out there somewhere):

I have tried many combinations of searches, without any luck:eusa_thin... so far.... I did try Rockler (who makes a similar cabinet, but they did not provide any leads...

And, yes, I will post pictures, etc. of the project..:wsmile:...

Thanks,
Henri

 

[sawduster]

Seems to me that this could be replicated fairly easily with a scroll saw and some BB Ply :eusa_thin
....Just a thought

 

[JCraig]

May not be exactly what you need, but could put you on the trail.

http://www.alibaba.com/product-free/101015528/Butterfly_Vent_Side_Knob_Vent.html

 

[Sealeveler]

I searched for a grill draft control and found mostly grill stores,if you could find a grill part supplier.
Tony

 

[Rob]

Or find a grill someone is throwing out? Rob it off that.

 

[RoadRunner]

Well with all the suggestions, thanks everyone!!!!! It's been found....
http://www.boatersworld.com/product/MP80810202.htm
This one will work perfectly.....
Thanks to everybody.....
Henri

 

[merrill77]

I've seen such a vent on a commercial router table - and I can't figure out what purpose it serves...perhaps someone can enlighten me. I gather that it is to modulate air flow into the box...but why would you want to do that? Why would you ever want to restrict incoming air flow?

 

[Sully]

I think it's more a question of finding the "sweet spot" with regards to air flow. If there is too much flow, chips and dust are not cleared from the dust box quickly enough. If there is too little (i.e. none) flow, the same is true.

 

[merrill77]

If there is too much flow, chips and dust are not cleared from the dust box quickly enough.

Do you have any references for that? My research (most of which was from Bill Pentz's site) indicates that you can never have too much airflow for good dust collection.

 

[RoadRunner]

Good Morning - winter has arrived and we are burried....

The primary reason for the vent is to allow adjustment so that there is not too much vaccuum created inside the lower collection box so that the resulting suction will not 'hold' your workpiece down and limit/restrict it's movement as you are 'working' the piece.

Henri

 

[jhreed]

Chris, you are too young to remember the days before air conditioning. In our house we had a whole house fan in the hallway that drew air from the house and exhausted through the attic vents. I all windows except the one in your room were closed and your window was open only about 6" you would have a breeze strong enough to pull the sheets off the bed. I everyone else opened their windows the velocity would be reduced such that you could not even feel the breeze. You need sufficient volume to move the amount of dust & chips you are creating but must also have enough velocity to keep the debris air borne.

The theory behind a cyclone is, your volume remains somewhat constant, but the air travels around the outside of the cyclone instead of straight through. This greaty reduces the velocity so the dust can no longer remain suspended and falls out of the air.

It takes volume plus velocity to move the dust.

 

[jhreed]

Sully, we need Earl to jump in. If I remember correctly he has a modulating damper on his dc system. It automatically modulates to reduce vacuum before it collapses his dust bin but throttles the volume to maintain enough velocity to keep the wood waste suspended. He can have one or several machines running at the same time and the damper modulates to keep the system working efficiently.
James

 

[merrill77]

Chris, you are too young to remember the days before air conditioning. In our house we had a whole house fan in the hallway that drew air from the house and exhausted through the attic vents. I all windows except the one in your room were closed and your window was open only about 6" you would have a breeze strong enough to pull the sheets off the bed. I everyone else opened their windows the velocity would be reduced such that you could not even feel the breeze. You need sufficient volume to move the amount of dust & chips you are creating but must also have enough velocity to keep the debris air borne.

The theory behind a cyclone is, your volume remains somewhat constant, but the air travels around the outside of the cyclone instead of straight through. This greaty reduces the velocity so the dust can no longer remain suspended and falls out of the air.

It takes volume plus velocity to move the dust.

I think I'm following that train of thought...and I can see how it applies in a DC system where you have multiple runs - you must use blast gates to ensure that maximum airflow is directed to the tool you are using.

But I don't see how it applies here. I know that the flow of gasses is elastic - and the velocity can increase around the point of a restriction to maintain volume of flow. So wouldn't the velocity only increase right at the vent? As soon as the air enters the big cavity inside the router box, it is going to slow back down, right? The amount of space inside the cabinet has not changed.

 

[paul dyar]

I haven't thought about a vent like that on mine. I drilled 13/8" holes and used duct tape. Now I think I will make a vent like the one you are looking for. Thanks for the idea.
Paul

 

[Ken Massingale]

I just drilled 1/4" holes in the side of the bucket till I had the suction/draft right. Works great.