Projector mount / dealing with vibration

**Captain Rex** · **10-16-09, 08:16 AM**

My projector mount is attached to wood work/the trusses by four screws. However any time someone walkes through the kitchen above on the main floor, I get a vibration that shakes the picture a little. Any thoughts on how to fix this?

Thanks in advance!

**Ted White** · **10-16-09, 08:25 AM**

You might consider installing a decoupled panel. 4 resilient clips, two sections of metal furring channel and a piece of ply.
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**Captain Rex** · **10-16-09, 08:28 AM**

Ted, do you have a picture or diagram of this type of thing? I'm not sure I'm following the concept.

**Ted White** · **10-16-09, 08:57 AM**

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**Ted White** · **10-16-09, 09:19 AM**

This isn't a picture of precisely what I was describing since your ceiling is drywalled already. So imagine the ceiling is drywalled. Then apply the clips and channels. 4 clips, 2 channels.

Then attach a piece of MDF or plywood. You could router the edges up pretty. Attach the panel to the channel. The panel will move up and down like a shock absorber. This should help. At least it's an easy trial.

This make sense?

**tonyvdb** · **10-16-09, 10:21 AM**

Often what causes movement in the floor is that there is not enough bracing between the beams. By placing some 2x6 pieces across the gap in the area where the projector is mounted for about 4' around you will stiffen up the floor and it should not move nearly as much.

**MatrixDweller** · **10-16-09, 05:16 PM**

They make vibration isolation kits for projectors. i.e: http://www.htmarket.com/vibab.html

I don't have that problem with my projector, but my pot lights flicker when my kids jump on the floor above. The joists in my house are only 2x8's wherein something thicker might be better.

**tiggers97** · **10-19-09, 11:25 AM**

Quote:

MatrixDweller wrote:

They make vibration isolation kits for projectors. i.e: http://www.htmarket.com/vibab.html

I don't have that problem with my projector, but my pot lights flicker when my kids jump on the floor above. The joists in my house are only 2x8's wherein something thicker might be better.

Just decouple the projector, like above, instead of the entire ceiling.

Only other suggestion I would have is to move the projector to another location. But that may not be an option depending on your setup.

**Captain Rex** · **10-28-09, 02:49 PM**

I' already had everything pretty securely mounted and the dry wall up before I posted this. I'm going to see how the drywall affects it by adding rigidity.

I guess I was wondering if there are small shock absorber kits or something out there.

**MatrixDweller** · **10-28-09, 03:32 PM**

It's probably screwed into the joist though I bet. What you could try is putting a neoprene or soft rubber washer between the ceiling and the mount where the screws go though the ceiling.

If there is still a some movement a home made vibration damper could be made by adding a bracket with neoprene or soft rubber in between the mount and the ceiling. The projector mount screwed into the bracket and then the bracket into the ceiling. That way the screws that secure the mount don't transfer vibrations from the joists/ceiling. With that description you probably get the idea and could come up with a plan of your own.

If there is a lot of vibration then more damping is needed. One thing to consider too is that excess vibration transferred into the projector can also damage the bulb and could make it fail prematurely.

**atledreier** · **10-28-09, 04:20 PM**

I have my projector on a shelf suspended by four chains jung in the ceiling. I get alot of vibration too. I am going to get a set of springs and suspend the projector, and see if that helps.

**Ted White** · **10-28-09, 04:26 PM**

That chain scenario brings up a good point. The chain isn't a spring, just like a suspended ceiling isn't resilient. So isolation isn't as good as it can be.

**Bill Wilkinson** · **10-28-09, 04:42 PM**

Sometimes it is wise to 'sister' the joists and add cross bracing in the area where the projector is going to be mounted as the room is being constructed. This will stiffen the floor/ceiling assembly and reduce the vibration from a structural standpoint.

The trouble with trying to mount the projector with vibration damping mounts is that they are so light. There are very few materials that will function properly on those light loads. You could in fact make it worse as you could increase the amplitude of the vibration with the wrong pad.
Bill

**Ted White** · **10-28-09, 04:46 PM**

Not thinking sistering or otherwise stiffening will affect change in the small zone around the projector. The rest of the floor system will still be oscillating even though the small area around the projector is stiffened.

A resilient mount will have a better chance to separate the projector from the ceiling.

**Bill Wilkinson** · **10-28-09, 05:05 PM**

I should have been clearer. Ted you are right you can't do just a small area it would have to be sistered back to 'room edge support point' to be effective.
I love isolators and use them all the time but using the wrong one could leave you in a worst off condition actually increasing the amplitude. Perhaps as you have suggested using 4 mounts on two pieces of furring channel with a broad base of double layered plywood, Green Glue between the layers for damping. Screw the plywood assembly to the furring channel and the projector to the plywood base. Paint it to match the room. Does any company make a kit for this?
Bill

**Ted White** · **10-28-09, 05:10 PM**

Projectors are mounted on ceilings decoupled with clips as a common practice. But the resulting spring has a low resonance due in part to the mass of double drywall hanging on it. To your point, Bill, a heavier panel attached to this little clip assembly would ensure a low frequency resonance.

**Bill Wilkinson** · **10-28-09, 05:46 PM**

I think it would do a fine job. The only challenge would be to make it look nice enough to get the "wife approval". The clip and furring channel would keep the dampened wood 'base' off the ceiling by approx. 1-5/8" so if you put edge return molding on this to go back to within say 3/8" of the ceiling, leaving a reveal, it would look like it was cabinet work put in place to mount the projector.
Bill

**Ted White** · **10-28-09, 05:48 PM**

I'm thinking the mass would be much more critical than the damping in this instance. Not sure Green Glue would do a
thing, actually.

**Bill Wilkinson** · **10-28-09, 06:12 PM**

I'd want to be doing it while I was using Green Glue for something else. I would not want to waste a whole tube.
Question: Is this just an annoyance as someone walks over making the projector shake or can it actually damage some/all projects over time?
Bill

**steiny93** · **11-17-09, 03:07 PM**

i have a similar problem
but couldn't this by solved by the approach at the following link: http://www.vibrationmounts.com/RFQ/VM08003.htm

For the isolation material couldn't one use memory foam or simplily foam rubber? Then do the entire job where the mount attachs to the ceiling?

**tiggers97** · **11-17-09, 03:22 PM**

I think the material in the link would have to be much denser than memory foam.
(I'm thinking you mean the type they use in pillows)

**Ted White** · **11-17-09, 03:24 PM**

Quote:

tiggers97 wrote:

I think the material in the link would have to be much denser than memory foam.
(I'm thinking you mean the type they use in pillows)

I agree. Not thinking foam and pads are the answer here.

**steiny93** · **11-18-09, 09:21 AM**

oh yah, the material in the link was needing 20-120 psi i believe, guessing none of our projectors are getting into that range

my rational for this approach was that I could then focus the isolation to the contact point between the mount and the projector making a very easy retrofit

i'm guessing that lots of people have this issue and i can only find a couple commerical solutions, cheif as a mount that does it ($250) and there was another solution which did it via a mounting solution to the joist ($60). My guess is that there is a way to solve this problem without adding something unsightly to the ceiling or costing a couple hundred $'s

**bbieger** · **11-18-09, 02:54 PM**

I was digging around for neoprene washers and gromets a few days back and ran across vibration reducing mounts that would probably work pretty well. Something like this...

http://www.vibrasystems.com/?EC=Product&ProductID=60

While I'm no expert, it seems to me that it will be extremely difficult to add enough mass or rigidity to the ceiling or floor to dampen the vibrations of someone walking on the floor. Sure, you could easily stop hearing them..but the actual deflection is a function of your floor joists and sub floor (let me guess, new construction).

Anyways..it seems you need a solution that is going to allow your projector mount to move independently from your ceiling. Therefore, some type of double deflection hanger would work. The more mass you can add to your projector mount the better. I'm not saying go overboard or anything. But if you added a couple 1/2" thick steel plates to the mount, the mass of the mount would help the double isolation spring mounts more effective.

I think springs are the answer for you. My neighbor has a steadycam rig for a camera and he can literally jump up and down and the camera stay perfectly still. (but that rigs costs about 10k).

Oh yeah, another website with uber amounts of vibration mounts...http://www.vibrationmounts.com/Products5.htm If they make a vibration mounts suitable for electron microscopes, something tells me they can help you out.

Hope this helps.

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