Specs and sources for stainless steel chains

I have a two-bolt anchor on my property that is currently set up with two hangers, locking biners, and a nylon equalette. I have a pull cord through it that allows me to pull a climbing rope through. This is all intended so that I can climb up there by toprope soloing, without having to round up a belayer or lead rope solo (although I do have bolts that allow me to lead solo, and that's how I got up there to install the anchor initially).

The only way to inspect the anchor is by climbing up there, so I would like to back up the equalette with stainless steel chains. That way if the nylon decays over time, I can still get up there safely to replace it. About 1 meter of chains would be needed.

What is the normal set of specs for this type of chain? The ones at the hardware store or on amazon seem to have surprisingly low stated maximum loads. I wonder if they spec them with some huge margin of error, since many of their users might not understand much about dynamic loads.

Is there any vendor that will sell me a single meter of an appropriate stainless steel chain? My hardware store only has galvanized steel, and the only vendor that turned up on amazon in a cursory search wanted to sell 5 meters of stainless, which is way more than I need. Even if I didn't mind paying for the extra chain and the shipping, it would be a hassle to cut stainless with a hacksaw.

Is it OK to leave aluminum locking biners exposed to the elements for a long time like this? I could replace them with quicklinks, but then my knot wouldn't be able to pass through when I pull the rope through using the pull cord.

Check out McMaster-Carr - corrosion resistant chain for lifting. Looks like they sell 1', 2', 3', 4', 5', 10' lengths of various diameter stainless chains. They also probably have some sort of quicklink or shackle that would allow a knot to pass through.

The smallest has a working load limit of 1400 lbs. For industrial stuff like chains, the working load limit has a rather large factor of safety baked in. I think that x4 is pretty typical in this type of setting. So the small chain would have a minimum breaking strength of 5600 lbs or above.

If I understand correctly, strengths of climbing gear are minimum breaking strength which does not include a built in factor of safety. I'm sure that I am leaving out a lot of nuance but I think that this is basically why industrial equipment seems to have strength ratings that are frighteningly lower than what we would expect from our climbing gear.

@Gregory H: Perfect, that was exactly what I needed to know. Thanks!

Instead of chain you could just use some old climbing rope and put a couple of lockers on it and use that for the anchor.   Climbing rope lasts a long time in the elements.  I left an old 10.5 rope on top of a tower for over three years using it as a rap anchor.  It was exposed to sun, rain and snow the entire time and the sheath was very sun bleached.  I had it break tested and even after all that exposure it broke at over 2000lbs.  Thats way more than any top roping force you would or should ever subject it to.   If you want to be super safe just replace the rope an a yearly basis. 

BTW what area is this in?  That could make a difference?  

If you have bolted anchor there is zero good reason for equipping  it with nylon.  Period.  Get  4 quick links from  climb  tech. Two links on each bolt. That makes  a great  anchor with plenty of room for clipping.  If you need  extension for some reason  go to the hardware store and get section of logging chain.  5 /16ths is strong enough to tear the  bumper off your truck  but 3/8ths has more room in it for  clipping and running ropes through it.  Count the links so that including the screw link that connects to the bolt  hangers the last  link is hanging straight out from the rock.  Not laying flat on the rock. 

e-rigging.com is highly recommended! 31511081 is the product number. 3,550lbs working load should be plenty (17,600 min breaking strength). Would love others to weigh in on their preferred stainless steel chain vendors though!

Nick Goldsmith wrote:

If you have bolted anchor there is zero good reason for equipping  it with nylon.  Period.  Get  4 quick links from  climb  tech. Two links on each bolt. That makes  a great  anchor with plenty of room for clipping.  If you need  extension for some reason  go to the hardware store and get section of logging chain.  5 /16ths is strong enough to tear the  bumper off your truck  but 3/8ths has more room in it for  clipping and running ropes through it.  Count the links so that including the screw link that connects to the bolt  hangers the last  link is hanging straight out from the rock.  Not laying flat on the rock. 

From a previous post of his he was talking about putting a route up a tree in his yard, that is why I was suggesting the rope, not any rock walls in Fullerton that I am aware of unless he is talking about a home somewhere else.  

I've purchased 3/8" and 5/16" Stainless chain from E-Rigging before. I've also bought via https://usstainless.com/ No complaints! Roughly if you buy 3/8" hardware (quicklinks and chain) it will be more than strong enough.

+1 to using chain as a long term solution. I tend to equip anchors with a 20+ year mindset. Stainless chain is more expensive, but should not leave rust streaks!

Luke

Yes, this is in a tree, so the considerations are a little different than for bolts in rock. If I tweak this to the point where I get a setup that I like, I'll post a complete description as a separate thread. I imagine there are other people out there who might want to set up tree-top anchors for various applications such as slack lines.

Greg. Don't be a hack. Do a good job with whatever your task is.  Especially when you are installing life support equipment. 

 ben. In a tree for your own use old climbing rope  with a screw link is just fine.