Reducing dust passing in direct vented Clearvue

[George Yetka]

I fiinshed up installing my cv1800. And when testing it picked up a small pile and now my cars are covered in large dust particles not just the fines I expected. The only thing i can think of to help this is to straiten the suction side of the seperator. As you can see the duct coming in is angled slightly down. Outside of that I can recheck that all the seams on the drop section are snug and sealed. But I did silicone them all. Any other ideas or should i expect the dust im getting?
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[Frank Pratt]

The inlet to the cyclone needs to have a straight section feeding it. I don't remember how long, but the manual should tell you. The outlet needs to be either terminated outside or to a filter stack. Even when working at peak efficiency, the cyclone will still pass dangerous amounts of fine dust.

[Adam Carl]

Yes, they recommend at least 4 feet, this fact changed how I was going to configure everything. I am in the process of completing my own install. Waiting for some 8 flex hose to help me complete the vent outdoors.

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[Jamie Buxton]

I'm not seeing a chip bin in your photos. You must have a chip bin under the cone, and there cannot be any leaks between the bin and the cone. If you have a leak, air gets sucked up into the cone, and sawdust passes right through the top of the cone into the filter.

[John K Jordan]

I fiinshed up installing my cv1800. And when testing it picked up a small pile and now my cars are covered in large dust particles not just the fines I expected. The only thing i can think of to help this is to straiten the suction side of the seperator. As you can see the duct coming in is angled slightly down. Outside of that I can recheck that all the seams on the drop section are snug and sealed. But I did silicone them all. Any other ideas or should i expect the dust im getting?
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George, you should not expect the dust you described.

I have my ClearVue installed with the final section of 6" inlet duct coming in at an small angle due to constraints on my installation space. While a straight section of inlet duct is recommended for maximum efficiency, the angle on mine has not made any significant difference in the separation. My bin gets filled with even talcum-power-like fines from my drum sander and almost nothing goes to the filters and cleanout.

But I can't see the angle you mentioned in the picture. If you are talking about the angle of the rectangular section it's designed that way.

The only thing I know that will pass excessive dust to the the exhaust duct is a leak in cone or the bin. There will be a vacuum inside the bin, so strong that the first bin I made from a metal trash can collapsed from the vacuum! Make sure the bin is connected properly and the seal on the lid is perfect or the air that leaks into the bin will pull the dust straight up and out the exhaust.

If working properly, you can toss a handful of dust and shavings into the end of the inlet duct and watch the swirl in the cone as they slowly drop to to the bin. The swirl will be there for a long time - if it clears quickly there is likely a leak.

Jamie questioned if the bin was installed - if so, that would make a mega-leak!! Remember, ClearVue warns not to test or even turn the motor on until the system is completely assembled, including the collection drum. Doing so may cause the circuit breaker to trip, physical damage or you can damage up the motor!

JKJ

[glenn bradley]

Interestingly I was just reading about this in another thread. From the Bill Pentz site:

"Also, for maximum efficiency, particularly with a cyclone, this layout keeps a straight run that is at least 4' or longer going into the inlet. This keeps the incoming air very smooth making for far better material separation and improved efficiency as turbulence kills efficiency."

[Chuck Saunders]

To expand on Johns' point. Once the system is completely installed and ready for first start up you should monitor the load with an amp meter. If the amp reading exceeds the motor nameplate amp rating you will need to add a restriction plate to the inlet to reduce the amperage draw. Running a fan with no restrictions can result in the motor drawing excessive amperage leading to a burned out motor.
Chuck

[Carl Beckett]

I'm not seeing a chip bin in your photos. You must have a chip bin under the cone, and there cannot be any leaks between the bin and the cone. If you have a leak, air gets sucked up into the cone, and sawdust passes right through the top of the cone into the filter.

A critical piece of the overall system. Perhaps this is down below so you can dump it. But make sure there are no leaks as mentioned, I put a foam gasket on my bin lid, and caulked the hose joints.

I have a clearvue vented outside hooked up to a widebelt sander (think lots of dust!). It works well. You have something fundamentally wrong to be getting dust you describe.

[Jim Becker]

If you are getting blow by of actual larger debris, then you have something not setup correctly including a potential leak below the separation cone to the bottom of the bin. Anything coming out of the free exhaust past the cyclone should be minimal and "really fine"...largely not visible, in other words.

[George Yetka]

There is definitely a bin. I connected a piece of 6" spiral to drop it down into the garage. Sorry for the lack of good pictures. This picture shows the path of the inlet. I will redo this inlet in the next couple weeks. In the meantime I will run the dc and use a lighter to see if I can find a leak. And silicone anything I may have missed.
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[Carl Beckett]

There isnt much to them. Another possibility is if you are pulling through a small diameter, long tube as the inlet. If it is constricting airflow it might drop cyclone velocity and not separate well. Often times I will open a separate blast gate for this (keeps the volume of air going through the cyclone high).

Just a thought.

[Jim Becker]

There is definitely a bin. I connected a piece of 6" spiral to drop it down into the garage. Sorry for the lack of good pictures. This picture shows the path of the inlet. I will redo this inlet in the next couple weeks. In the meantime I will run the dc and use a lighter to see if I can find a leak. And silicone anything I may have missed.
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Even a "pinhole" leak between the cone and the barrel will cause blow-by. DAMHIKT!!!!

[Charles Lent]

Rather than using a lighter you should use a smoke source, but whatever you use, make certain that no sparks enter the dust collector through the leak. Fine saw dust suspended in air can be very explosive. A safe way to make smoke for this is to buy a spray can of smoke test used for testing smoke alarms. Just spray it near where you suspect a leak to see if it's drawn in.

https://www.amazon.com/Home-Safeguar.../dp/B001MYM7EK

Charley

[David Utterback]

The rule of thumb from the ventilation design course I completed is 7 pipe diameters of straight run to achieve laminar flow. This is true in all duct work including distances between individual inlets and even large radius elbows. Of course, who has a shop large enough to adhere to these rules? But the more you do, the greater efficiency you will get.

[George Yetka]

I ended up thinking about this prior to doing anything, and ended up just running some silicone over everything to start I got 3 of the 4 joints and at the 4th joint my drop tube seperated as I hadnt had a chance to support well. So once I have a set of hands Ill get it back up and supported properly and re silicone it.