Here's a bunch of ideas I pulled from around the web:
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I found some elastic bands about 4 inches around and the same thickness as the real thing at K-Mart.
30 bands with a molded seam that work perfectly with 2 sizes of shock mounts I have. My MXL and Rode. I paid maybe $2.00 for the 30. The brand name is SCUNCI in black with 2 dots above each leg of the maginta colored "U" and beneath it is "DREAM-IMAGINE-CREATE" in black letters on a white card with a magenta and black stripped bottom. Top right corner is a number 17278-A.
They are nice and thick like the shock mount bands are, about 3/16" thick. Seeing how I paid $5.00 for 2 of the "real thing" these are a good enough of a deal. With 30 of them, I can replace them as needed. Now we'll see how long they last. Here's a link to some that look similar. My card is 6 1/2 inch long by 2 3/4 inch wide. Here's a link to something similar...
http://www.amazon.com/exec/obidos/ASIN/B000BM3EWS/sz-category76-20/ref=nosim/104-5633458-2130363
The back of the pack says to go to scunci.com I did and found these that look similar too....
http://www.scunci.com/product_detail.aspx?gid=4&pid=92&lp=7
Just go to K-Mart, maybe it was a special package for K-Mart to sell cheaper.
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The rubber band size needed for most shockmounts are about 5" rubber bands...
The only 5" size commonly available is 5/8" wide... too awkward for use on shockmounts.
The only usable size that is commonly available are the 7"x1/8" rubber bands for use on file folders. I bought a package in assorted colors from Staples. Since they are 7" an I need ones that are 5"... I simply tied a knot in it to yeild a 5" rubber band.
IT WORKS... I replaced the elastic on two shockmounts. Now all I have to do is get used to having purple and blue rubber bands on the shockmounts. These 7" rubber bands sell for 99 cents a dozen.
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I found the rubber O-Rings in the Plumbing dept at Home Depot that matched up with the original ones. They cost about 25 cents each. They don't last any longer than the originals.
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Goody Ouchless #01007 size elastics (for hair). They are the perfect size and you should be able to find them (cheap...I mean real cheap) in just about any drug store (I got mine at a Rite-Aid). They come in a variety of colors and they last a good long time.
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I buy very oversized rubber bands... 1/16" square in section and about 10" in diameter.
I just tie a knot to get the desired diameter as the elastic I'm trying to replace. These giant rubber bands are about $1 for a dozen.
It lasts a lot longer than the braided elastics.
It doesn't look too cool... but it works... form follows function.
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What you want is called shockcord, available from any marine supply house. Try BoatsUS or West Marine. I would think that mic shockmount cord is either 1/8 or 3/16 inch thick.
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I also found another brand "Distinctly Basics" at the Dollar Store. 24 for $1 item#F808 SKU#1901032.
