I have access to drilling line, it's a braided cable that ranges in sizes but the stuff I have is 1 1/8" in diameter. After reading a thread about leaf springs, I wonder if it would be safe to make into blades or just to use in general. its only used on the rig for a matter of months, but it obviously goes through some intense stress during that time. so... is it safe?

To eat..... no.

What exactly are you worried about ?

I hear words like fatigued, micro-fractures, and [poor] crystalline structure, and I wonder how much these would apply to used drilling cable.

As long as the strands are not broken the possibilities are endless. The broken strands will make the blade look not as clean after the etch but could cause cold shuts in the weld. A cable blade is so welded, twisted and hammered that any stress it received in it's previous life will be forged out. A good guide on forging cable is in the book "The Complete Bladesmith" by Jim Hrisoulas. Be sure it's all steel and not the fibercore type. Happy hammering!!!

You're going to forge-weld the stuff, right? No worries about micro-cracks if you can weld up macro-voids.

You're going to be heating over and over, yes? Crystal structure changes by heating & cooling. New grains nucleate every time you heat up.

Fatigue? Erased by what you are going to do.

Mind you, I would NOT use the cable for rigging anymore.

Mind you, I would NOT use the cable for rigging anymore.

Kind of hard to once it's a solid bar LOL

i have around 20 feet of super compact striated winding crane cable or wire rope, this post reminded me of it! I think i need to make some damascus out of it. Ablenumbersix, i think you will be fine.

May want to look at the original cable and see if there is any core or other weird stuff in there, before you forge..

thank you for putting my mind at ease, I was worried because this is going to be a giant source of free metal for me and I would hate for it to be unusable.

There are two main areas of stress fatigue in a drilling line First is the combined stress of bending around the pulleys as the load is picked up and the second is the lap points on the pickup spool. The drilling contractor addresses these with a technique of "slip and cut". Every so often (based on ton miles of pickup) he will slip a bit of cable from the storage spool and move the pickup points, then every so often he will cut a part of the line to the spool and move the lap points. This means the stress is spread out, but as others have said, heating and reheating makes the high stress areas moot. Use and enjoy your cable (wire rope). Drilling line rarely has a core of some other material, but logging cables do.

I could also add that drilling line is like a mountain climbers rope. If it fails in service, someone is likely to die. It is therefore retired well before it is worn out.