Use where extreme flexibility is not required, but abrasion resistance is advantageous.
7 x 7 wire rope is commonly used in aircraft and automotive controls and as lifelines on boats.
It performs well in a wide range of mechanical applications.
Among the 3 common braids of marine wire, 7 x 7 has the smallest metallic cross-section, and therefore has the lowest strength of the three.
With larger wires than 7 x 19, but smaller than 1 x 19, it falls in the middle as far as flexibility.
• Price is per foot; full spools are 500 ft (except 3/16" full spool is 250 ft)
• Note: BL (nominal breaking strength) and weight (lb/100 ft.) are approximate.
Heavy on the technical side...
Which alloy to choose?
If you have a choice between the most common marine stainless steel alloys — 304 and 316 — which should you choose?
304* is the stronger (by about 15%) and more economical of the two alloys commonly used for rigging. In the middle range of corrosion resistance provided by stainless steels, it is often used for rigging on boats in cooler climates, like the Pacific Northwest of the United States.
316 stainless steel alloy provides increased corrosion resistance at the cost of some strength. It is the alloy of choice for rigging — especially in tropical climates where higher temperatures and saltwater combine to make corrosion a significant concern.
*304 stainless steel is also referred to as "18/8", denoting its 18% chromium and 8% nickel components.
316 alloy adds 2 -3% molybdenum to the basic 304 formulation to increase resistance to pitting caused by chlorides.
Reference: ASM Specialty Handbook - Stainless Steels; ASM International, 1994