Steel locking carabiners

Jacob Ward wrote:

How is using two biners less overkill than just one?

do you know what an ANSI certified trilock biner is? it's overkill for recreational climbing. it would be like belaying with a rig instead of a gri gri..  why do it???

I use 2 steel ovals and a steel locking oval at the master point on top ropes when running scout groups / other students. 3 gives wider bend, steel has less friction than aluminum and it keeps ropes cleaner (Aluminum Oxide) and they pretty much never wear out! This past year I started using all steel in my climbing program (steel figure eights, steel HMS carabiners on Belay devices, Steel carabiners for quickdraws.) last week we did a multi day climbing camp and ropes are a hell of a lot cleaner. 

Tamiban Gueterstan wrote:

Lol yeah, it's about 3-5 times heavier than aluminum depending on how small of a carabiner you're comparing it to. I guess my question is that, if there's a case for using steel for sandy environments or as a workhorse for TR guiding, can we use just one if it has an ANSI gate?

Or alternatively for an aluminum carabiner like the Petzl Bm'D which has a ANSI gate and is only 20g heavier than similarly sized aluminums, can we just use 1 in place of every application where we use to think 2 lockers were necessary?

To address a post above, I'm a bit skeptical that any single round barstock steel carabiner is harder on the rope in any meaningful way for TR. And that the benefits of redundacy versus a single ansi gate locker are more emotional than practical.

It has nothing to do with emotional feeling. Using more than one isn’t just for redundancy. More carabiners gives a greater radius and less damage to your rope and easier to belay and lower. Using steel is smoother than aluminum due to reduced friction. And finally keeps rope cleaner with less aluminum oxide transfer. Some might not notice a difference. However, run a climbing program with many participants (especially in easier/ low angle climbs) and you will notice a huge difference. Steel will take the abuse of people using gear that isn’t theirs and don’t really care, plus it will last longer (especially when running a program)   Also some programs have guidelines, specific standards and insurance requirements (I don’t always agree with a group of people who wear suits and ties, sit in an office and tell us how to run a program when they know nothing about climbing) but for liability reasons I will put that extra carabiner in. Tell what harm is done adding another carabiner, or making it a locking one? As a rescuer, I have seen accidents due to cutting corners and trying to save a $4 piece of hardware.

Be safe and put the odds in your favor so you can climb well into “Old Age”. 

Just to help out; the coefficient of friction on polished steel and aluminum for nylon is identical.

Two biners gives more friction than one.

Which gives more wear on the rope is unknown.

Jim Titt wrote:

Just to help out; the coefficient of friction on polished steel and aluminum for nylon is identical.

Two biners gives more friction than one.

Which gives more wear on the rope is unknown.

Steel are generally nicer to the ropes because of the buildup of aluminum oxide once anodization has worn away on aluminum lockers. 

I know.

Jim Titt wrote:

Just to help out; the coefficient of friction on polished steel and aluminum for nylon is identical.

Two biners gives more friction than one.

Which gives more wear on the rope is unknown.

I was gonna post this about the coefficient.  

The state of the rope sheath and how dirty it is will have much more effect than the type of metal.

I have a paper that was done for various condition arborist ropes and how well they pull through aluminum or steel retrieval systems which covers basically what is being discussed.

Somewhere in the cloud if folks are interested I can prob dig it out with a bit of a effort.

rappel on a steel figure eight and an aluminum figure eight of same size, or a brake bar rack with steel bars and one with aluminum bars and tell me you cannot feel a difference?

I have rappelled on a six bar rack with all bars engaged and felt it was fast, and I have rappelled same manufacturers rack with aluminum bars and had 3 bars engaged and felt it was slow.  I am using steel figure eights in my youth programs now because we had issues with kids who weigh less than 60 Lbs. having to much friction, so we were then rigging in "Speed Configuration" to solve issue, This year with the polished steel eights rigged in standard mode, we had no issues. 

YMMV, but these are my experiences over many decades. 

jc5462 wrote:

rappel on a steel figure eight and an aluminum figure eight of same size, or a brake bar rack with steel bars and one with aluminum bars and tell me you cannot feel a difference?

I have rappelled on a six bar rack with all bars engaged and felt it was fast, and I have rappelled same manufacturers rack with aluminum bars and had 3 bars engaged and felt it was slow.  I am using steel figure eights in my youth programs now because we had issues with kids who weigh less than 60 Lbs. having to much friction, so we were then rigging in "Speed Configuration" to solve issue, This year with the polished steel eights rigged in standard mode, we had no issues. 

YMMV, but these are my experiences over many decades. 

The friction coefficient disagrees but perhaps thermally something is at play here.
Maybe that the steel takes longer to heat up under use, thus feeling more slippery until it does? The play of hot metal on cordage is a potential I haven't thought too deeply about.
Time to dig a into this little tangent or perhaps someone has already been down this rabbit role...