Vibration transfer of chain vs cable?

[Perry Holbrook]

I'll be installing a Clear Vue cyclone soon. It will be outside the shop under a roof I'll have to attach to the back wall. I plan to "hang" the cyclone from the roof joist. My concern is vibration. On the second floor of the shop I have a glass fusing kiln that I run daily. "Any" vibration of the kiln is a bad thing so I want to be sure any vibration from the cyclone is not transfered to the shop structure.

My current dust collection fan is in the same area. When I installed it I bolted it to the outside stairs going up. That set up vibrated too much and I had to mount the fan on its own support, which I really don't want to do for the cyclone.

So my question is, would a heavy chain transfer less vibration than a wire cable? Or a heavy bungee cord? Or a rope? Or something else?

Thanks, Perry

[Jamie Buxton]

If you hang the machine from chains or wire rope, they'll both be pulled taut, and will transmit vibration. Your first step is to use a well-built impellor, which is well-balanced. It will make less vibration than an unbalanced impellor. Your second step might be to use vibration-isolation machine mounts. There's a whole industry producing various kinds of these. McMaster-Carr sells them. Go to www.mcmaster.com, and enter "vibration" into the search box.

[Jeff Duncan]

If you want to avoid vibration I strongly suggest having the cyclone on a stand not attached to the building. Hanging one from any kind of chain or cable I'm thinking is going to allow excessive movement. I just don't think that's a good idea and may well lead to other problems you haven't yet thought of.
JeffD

[Peter Stahl]

I think your best bet is a stand. Penn State Ind. makes a stand for their cyclone, maybe your clearvue would fit in that. Or see if Clearvue has any suggestions for mounting on a stand.

[Tom Veatch]

Perry, I note that you have "any" in quotes. Not sure what that means, but taking the literal meaning, you're going to get some vibration transfer with any connection to the structure. A perfectly statically and dynamically balanced impeller would be ideal, but not very likely. Assuming the impeller is mounted such that the rotation is in a horizontal plane, most of the vibration from imbalance will also be in that plane - note the "most". There can also be a vertical vibration component from dynamic imbalance which will probably be a lower order of magnitude.

Of the three suggestions mentioned so far, hanging from a flexible support (cable/chain) would isolate the horizontal component but do little for the vertical. It would also likely lead to fairly large horizontal and rotational excursions of the cyclone body and fatigue problems with the ducts and/or joints. I wouldn't recommend that approach.

Attachment to the structure through vibration isolation mounts could reduce the vibration transmitted to the structure, but that isn't guaranteed. Vibration isolation is a complex topic. The masses involved, vibration frequencies, damping coefficients of the isolators, and geometry of the attachment pattern all have to be considered to reduce the vibration coupling between the impeller and the structure to it's absolute minimum. In a worst case scenario, if a natural frequency of the system is excited, it could actually increase the magnitude of the vibration felt by the structure. You can roll the dice and try that approach.

The best solution is physical isolation of the impeller from the structure by mounting the cyclone on a separate stand not attached to any connecting walls. I would also recommend a short section of flexible hose between the cyclone inlet/outlet and the ductwork to isolate the impeller from the ductwork. Fabricating a stand would not be a difficult task either from steel shapes with a little welding skill or even from construction grade dimensional lumber with moderate carpentry/woodworking skills.

[Rick Levine]

Perry,

I don't know if you have purchased your cyclone yet but if you haven't you might want to consider the Woodtek one. It comes with a stand and has a 1 micron bag that hangs off the unit. It is also designed to be hung but I used the stand instead.

[Perry Holbrook]

Sounds like you think this may be a challenge. Since most of the things I do in the shop seem to go against conventional wisdow, I think I'll accept the challenge. I found some isolation pads at McMaster that look like they will work. I can run an eye bolt thru them to probably a chain to the cyclone. If a chain doesn't work I'll try a nylon cord. The cyclone will be attached to the ducting with a flexable fitting just like I have on my existing system.

I can always add a stand if this doesn't work. I'll have a rather unusual chip collector under the cyclone and the legs of a stand will be an obstruction.

Thanks for the input,
Perry