Suspension requirements for 6 in. PVC

[Jim C Bradley]

Sorry to bug you. I know I have seen requirements to suspend 6" PVC but my searching does not find the info.
I am suspending 6" PVC ducting about 5 feet below the rafters. I am using chain. How far apart should the chains be? My gut feeling is that 4 feet would be fine. However I will gladly do 2 feet if that is the correct thing to do.
I assume I should use a chain at all junctions.
I plan on dry friction fit with duct tape to seal.
Second question: Are chains fastened directly to the PVC and directly to the rafters going to be a noise problem?
Enjoy,
Jim Bradley

[Matt Meiser]

I think mine is supported roughly every 4-5 feet, plus anywhere else I thought it to be important. It is pretty stiff, even at the joints if they are screwed together with a couple screws (don't glue it.) I used the giant zip ties and big screw eyes to hang mine.

[Jim O'Dell]

I hung mine with the black-solid rubber bungee cords. Eye hooks in the ceiling, and probably about every 5 feet. One 9' run of solid pipe doesn't have one in the middle, but definately one at each fitting, like Matt suggested. Mine doesn't move, and I don't hear any vibration noise from the ceiling. I will have one down tube at the wall where it will be anchored directly to the OSB. Time will tell if that is noisey or not. Didn't seem to be when I had it up temporarily and anchored to the studs before the OSB was installed, but that may make a drum surface for the noise to radiate from and I'll have to come up with a shock mount of some sort. Oh, and my bungee cords loop under the pipe and back to the ceiling, not ceiling to pipe. That probably won't work for you unless you hang chain down, then loop a bungee cord down, around the pipe, and back to the chain. Jim.

[Jeff Miller]

I didn't tape or seal mine with anything just 3 self taping screws at each joint, just push them together until tight, I have absolutely no leaks:)


JEFF:cool:

[Merle Clor]

Jim,
I hung mine about every 4-5 feet with plastic perforated tape like used to hang HVAC ductwork. I used molly bolts in the drywall ceiling. Put 3 screws into each junction and wrapped with metal tape. That was about 4 years ago and I haven't had any problems with it or any noise conduction.
Merle

[Yuchol Kim]

Here is how I hung mine, not done yet.

I just typed up a whole paragraph and pressed the wrong button. ;~(

I used metal channel electriciansn use to hang conduits. Channel is $11 for 10 footer from HD, 1/2" threaded rod is $5 for 10 footer from HD, nuts and bolts, etc.

For regular sections, I just drilled a small hole on metal adjustable hose clamps, screwed it into wall/ceiling, and tightened it around the pipe.
For the main intersection, I used the channel described above because it's heavy with all the fiitings. Also having few blast gates there means I'll be constantly be opening/closing = lots of stress.

I dry-assembled the whole thing, put some short screwed at each joint (short to not cause clogging) and applied caulking. To make it easily modified at a later date, I cauled AFTER assembling everthing.

I hope this helps.

(I hope the pictures show up)

[Yuchol Kim]

Some more pics

[Paul Simmel]

Yochol,

That is one sweet setup. I’ve roughed out my DC with HVAC pipe and fittings and once all is as I like it, I will be switching over to a S&D pvc system.

I think your hose-clamp idea is great. Simple/easy… strong I’m sure. My stuff, because the shop is new thus I may still move some machines around, is temp-hung with # 14 wire.

Just for grins… I’m curious… are you going to make any changes? Or is this system for you the “perfect” setup.

[Yuchol Kim]

I have spent 2 years moving my machines around the shop, looking for the setup I liked. Meanwhile, I moved the DC hose from machine to machine when I used them. (had Jet 2HP DC w/ 5 micron filter, which is replaced with Grizzly cyclone). I finally found a machinery setup that I REALLY like, so I don't expect things to change much. I have drops about every 10 feet, so changes shouldn't be bad. Thanks for the compliment.

[Jim C Bradley]

Yuchol
Your pictures are great. They really show how you did things. I am REALLY impressed with your layout and attention to detail.
Thanks a million.
Jim

[Jim C Bradley]

Thanks to all of you! I am going ahead with support at all junctions instead of every so many inches.
I come up from the DC into a triple wye. This gives me three "mains." With the three mains, wyes and drops I do not have any long runs now. In fact, as of today's redesign, my longest run is 52 inches.
Obviously this is a work in progress. I have started hanging. I will finish Monday (have to work Saturday, LOML gets my attention on Sunday).
Change of subject:
Went to Pomona Woodshow. Had a great time. Drive home took less gasoline because my wallet was lighter. Was accidently given the wrong bandsaw conversion kit by Woodline USA. Called them. Wayne, one of the owners returned my call and gave me outstanding service. I was truly impressed.
Enjoy,
Jim