Posted by: "Rob Danielson"
> I tried six of the larger sizes of the elastic cording from a fabric
> store-- either too weak or too stiff-- similar performance to Rode's
> stock cord. The Buna-N rings in the sampler I got from Allorings were
> really stiff. I ordered some large Silicon O-Rings tonight. #151 =3D 3"
> ID; #153 =3D 3.5" ID; #156 =3D 4.5" diameter. They purport only 5%
> stretch, but certainly worth a try. Thanks! Rob D.
The place you need to look for elastic cording is outdoor stores. The
marine grade is usually the best. Little that you find in a regular
fabric store is going to be ok on this. The biggest problem of all the
elastic cording is that it tends to slowly stretch out under use. You
need to have a method of taking up the slack as it does so.
The silicon o-rings that Rycote uses are very small diameter material
(and probably metric sized), the larger the diameter the stiffer they
get. I can stretch the 1" X 3/32" silicon o-rings I use in the sass
about 50% without breakage, but that's far more than is needed in a
suspension. You need stretch enough just to insure that during vibration
the tension does not go to zero.
Of course the vibration isolation I use in the SASS is different, there
I'm depending on a slight compression of the o-ring material rather than
stretch. The silicon is just a barrier to vibration transmission. Works
well at that.
Walt
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