material to make acoustic cover

Apr 01, 2007 2 Replies

Hi, I need to make a cover wich can block most of the noise from a 1M long shaft inside some equipment wich has little else in it beside the shaft and some bearing blocks.



Idealy it would not be very heavy, easily fabricated and able to serve as a cover under its own strength. with unsuported areas of 200mm x 100mm.



Ive used sound deadening pads before, even resorting to some spare roofing felt on the inside of washing machine wich was pretty effective, but I havnt got a cover as such to atatch it to.



cardboard would be strong enough, but needs something rubbery to absorb the sound, can you get rubberised cardboard ?



rubber sheet would be good for sound deadening but wouldnt take a shape and keep it, not sure plastic would be any good at absorbing the sound.



best bet so far is to make a thin aluminium cover and atatch sound deadening pads to it, but I was wondering if there was anything better, although you can actually get aluminium sheet lamintaed to a layer of sound deadening wich is a bit expensive but might be worth it.



Colin =^.^=


If you are trying to keep sound that is traveling through the air from getting through, it is one problem. If the whole assembly is vibrating it is a different problem.

Two layers of material that only connect at the anchor points will work fairly well on sound traveling through the air. The inner layer should have a few small holes in it. When you tap on the cover it should go "thump" not "ding" or "clank". If it goes "ding" try putting a small bit of visco-foam between them.

Sound traveling on the mechanical part, requires that you provide for a mass on the cover and a way for it to stay still while the other stuff moves. Some of this can be done with just how the cover is shaped. If it is mounted at its edges, running zig-zag bends in a band near the outsides will allow the cover to flex at that point. Running an "X" shaped bend through the middle will prevent the bulk of it from bending.

I've seen sponge rubber with a latex(-like) deadening layer in it. it was used to line printer cabinets (for noisy impact printers)

It may be rigid enough as it is or you could glue it to some cardboard etc...

Bye. Jasen

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required