Layout options

[Mike D]

I don't have fancy SketchUp drawings, but my sadsack screenshots illustrate a question I have: better to prioritize a straight run into the collector, or shorter runs overall?

My collector will be in a centrally located closet on the left.. bottom of the shot will be a panel saw, center is table saw/router, then mitre saw and drill press along the right wall.


​​​​​​All input appreciated!

 

[Rushton]

Hi Mike, did you intend to post three different layouts or just the two? In any event, here are some thoughts based on my reading and past comments from others:
1. If you are installing a CV1800, length of run should not be much of a problem in the space you've shown
2. Straight runs rule!
3. Closely spaced Wyes will add to turbulence in the run (as in your first image on the left) - it's good to separate them by a few feet
4. Remember to keep 5' of straight run

 

[jsbrow]

Mike D,

From what I have read having a length of uninterrupted straight pipe going directly into the cyclone helps smooth the air entering the cyclone which is a good thing. If I recall, the minimum length is 5’ although I may be mistaken as to the minimum length. As to overall length, every foot of pipe and every turn in the pipe adds static pressure to the system and thereby reduces air flow. Once the minimum length of straight pipe into the cyclone is achieved, then a layout that minimizes the length of each leg of pipe with the fewest turns back to the cyclone should optimize performance. My reference book states that adding a single 45 degree elbow is equivalent to adding 6’ of 6” diameter pipe; 12’ of 6” diameter pipe if a 90 degree elbow.

Sketch 1 would be my preference. Sketch 1 seems to use less material, reduce ceiling objections, and minimizes turns back to the cyclone.

Sketch 2 introduces a 90 degree turn on the way back to the cyclone from the drill press by the introduction of a second 45 degree elbow. The added 45 degree elbow would increase cost and static pressure. Sketch 2 also shortens the length of uninterrupted pipe entering the cyclone.

If you think you may ever add additional tools such as a planer, jointer, drum sander, band saw, lathe, down-draft sanding table, or some other tool, adding wyes that are capped in appropriate locations would make adding additional duct work easier when the time comes.

I saw no difference between sketch 1 and sketch 3.

 

[Mike D]

I added my 3rd option to the original post, which I had somehow missed. All these plans are probably over simplified, unfortunately, because there is a massive bit of ducting to deal with all along the right wall.
Those numbers regarding elbows vs run length make it pretty clear that elbows are the enemy in my small area, rather than run length. Very helpful.

I think I'll have to re read the parts of the forum about bending pvc; I assume a gentle curve is better than a 45, but worse than a straight run.

 

[Rushton]

Mike, my research told me that it is very difficult to successfully bend 6" PVC without getting kinks in the bends. The kinks are worse than using 45 degree elbows. I decided to abandon that thought and buy the elbows I needed. If you're using the white D2729 pipe, the best pricing I was able to find was Zoro.com with the Genova brand PVC parts at this link:
https://www.zoro.com/search?categor...q=&brand=GENOVA&variants.attributes.209600=6"

 

[Mike D]

Mike D,
My reference book states that adding a single 45 degree elbow is equivalent to adding 6’ of 6” diameter pipe; 12’ of 6” diameter pipe if a 90 degree elbow.

Interesting. Based on the number of people/sites that recommend using two 45s instead of a 90, I would have expected the 90 to be more than twice as bad as a 45.