Projector Isolation

[Esoteric]

Hey guys, so I have a client who has two Sanyo projectors mounted with Chief mounts, 1.5" pipe, and pipe flanges secured to the building steel.

The problem is that the bass drum hits on a frequency that makes the building steel vibrates and the vibration is being passed through to the projector and making the image jump.

Does anyone have any ideas on how to isolate the projector from the steel and stop the vibrations?

And yes, the projector must be rigged from the building steel in some way.

Mike

[prochlea]

Chief CMA 347.

It puts a weighted spring system between the projector and the building steel. Doesn't fix everything, but it's the best thing I've found. The downside is that the thing is like a 3' diameter setup...

[Frank DeWitt]

The good news is that these problems can be solved. the bad news is that often it takes a custom solution. There are a bewildering array of solutions out there, the right one depends on two things. the frequency that is exciting the vibration (The base drum) and the total weight of the projector and mount. BTW are both projectors working together as one or are they in two locations pointed at two screens?

If you can't find a off the shelf solution, you can contact companys like Lord

http://www.lord.com/products-and-sol...on-control.xml

Or Barry
http://www.barrycontrols.com/products/index.cfm

They will want to know the weight and frequency and what you need to do, what is good enough?

BTW Weight is your friend, and a big footprint is your friend. If I were working on this in my field (Optical mechanical) I would want the projector hanging from a big heavy plate. (2 or 3 ft sq.) The plate is fastened to the building in 3 places with something soft (The professional mounts) The vibration from the building steel must pass through the soft mounts and get the big heavy projector and plate moving. It is easier to turn the vibration into heat in the soft mounts.

To visualize this, a old trick for a poor mans vibration isolation table is to set a heavy steel plate on 3 small lawn mower tire inner tubes inflated soft, then adjust the presure so the main vibration is isolated. It works amazing well but I wouldn't recommend it for a projector because it is to soft and the image might wander. I mention it only to illustrate the concept.

Frank

[cmchamp]

Another option might be to re-tune the kick, re-voice the system, isolate/reduce the sympathetic vibrations to the building... probably too late for that now.