The usual choices for railings and architecture applications are uncoated 1/8", 3/16" diameter 1x19 cables of type 316 stainless steel. The reasons: strength, durability and weather-toughness.
Cable Diam: 3/16"
Minimum Break: 4183 lbs
Safe Workload Limit: 837 lbs
*Safe Workload (20% of breaking strength) is the maximum load which should ever be applied to a cable. The Safe Workload, not the Minimum Break, should always be load level used when designing and engineering custom cable assemblies.
We recommend only 1×19 construction, type 316 stainless steel cable for cable railing applications. 1×19 strand cable is engineered to hold static loads without stretching, and it is relatively stiff. Other cable constructions are not recommended because of their elevated levels of stretch and lower breaking strengths in comparison to 1×19 construction.