At Last - Ducting...

[Scott Bernstein]

At last...finally got around to installing some permanent ducting for the ClearVue Cyclone. This is the CV1800 with 16" impeller upgrade. It is on its very own 240V 30A circuit. I have not fully enclosed the closet yet, and will upgrade the rubber extension cable to the motor with armored cable when I do so. In between the closet wall offset studs is rock wool insulation and the interior is lined with mass-loaded vinyl. For exhaust, I will construct some kind of baffle. Maybe have the air leave the closet around where the intake pipe exits...not sure yet. One mistake I made was to hang the whole system off the cinder block wall in the back of the garage - may have been quieter if I had used some kind of vibration isolation hangers or made it freestanding. Oh well...fortunately it is not actually very loud upstairs. Louder than the dishwasher but not nearly as loud as a hair dryer. This ducting is so much better than the 25 feet of 6" flex tubing with two 4" flex extensions. I was constantly having to lug those lines around, usually tripping over them in the process. The suction was extremely strong with the flex lines, but this is even better. With only two open 4" ports the air velocity is too high to measure with my wind-vane flow meter (maxes out at 8500f/s), but with the last four 4" ports all open I am getting total CFM of approx 1750, closer to 2000 CFM if I measure the ports closer to the cyclone. If this 1750 CFM is accurate and we make some assumptions, that would be an airflow velocity of around 8900fps in the main line. Seems like plenty. I have three different brands/types of 4" flex extensions. One is the heavy-duty thick-walled flex that ClearVue sells, then the blue flex from Rockler and lastly some very light & supple 4" flex which has virtually clear plastic (can't remember where from). All have the spiral internal wire for support. The flow from the Rocker and Clearvue 4" flex is comparable. The flow velocities in the clear soft flex is significantly lower, by 1,000 feet-per-second, regardless of which port I use it on. The inner diameter is the same across all these. Obviously smooth-walled pipe is much better than flex line, but even the type of flex does make a difference.

From a purely subjective point of view, this system really sucks! It is fun to watch the numbers on the Dylos particle meter across the room decrease as the system runs.

SB


431555

[Ole Anderson]

I would think that hanging the system off a masonry wall would be good given the mass of the wall and its ability to absorb vibration. I hung mine off a 10" thick poured concrete basement wall. Yikes, I thought my shop was tight...

[Scott Bernstein]

Yeah...that's a pano shot of pretty much the whole shop, along those two walls. Of course everything is on mobile bases including the cabinets with the pantorouter and the sander/dewalt planer. So when the car is out of the garage it's not so bad.

[John K Jordan]

For the air returned to the shop I built a baffled return duct. There is almost no sound coming through the duct. With the closet having staggered stud walls and insulated for sound all around and above, my ClearVue is quiet enough when running to hear a whisper outside the closet.

I built the return duct from plywood has several turns and has a rubber coating sprayed inside to help absorb sound. In my case the shop ceiling has roof trusses above so I was able to squeeze the return duct into the trusses with a bit of effort. This was my design drawing. I apologize if I've posted this before in a thread but I can't keep up!

431657

If in a basement shop with another floor above I might build duct up against the ceiling, shallow in height but wide enough to to keep from restricting the flow.

JKJ

[Scott Bernstein]

That looks great; I was thinking something similar. I guess the idea is to have as many turns as possible without being restrictive, and an acoustical absorbing lining of some type would be a bonus. I'll report back once I have my baffled return duct built.

[Jim Andrew]

Hope you have really good anchors in that block!

[John K Jordan]

I'm not sure how many turns are needed but at least several should help. Not easily visible in the drawing are a couple of plywood baffles which may help as well. Can't remember, but I think I designed the cross sectional area of the duct to be almost five times the area of the 6" input duct to make sure I didn't restrict the air flow.

[Scott Bernstein]

Hope you have really good anchors in that block!

I have six 3" x 1/4" Tapcon screws. Seems to be holding thus far!

SAB