Review: Black Diamond Magnetron

A short study in gear, pop culture, human evolution and the scientific method

Rocklock Magnetron in situ.

Rocklock Magnetron in situ.

2001 A Space Odyssey is one of my favourite movies. Not that I have any real idea what’s going on – especially at the end with the flying through space and the light and the sound – it’s just that when I bring it up in conversation it makes me sound cultured and smart. The scene I love most is at the beginning: when the obelisk appears and the apes are slowly guided towards understanding and using tools. The mix of fear, awe and desire is riveting.

Leaving aside the delicious idea that our terrestrial domination (ironically, one and the same seems to see us currently hurtling towards total climate-induced ruination) came via a subtle push from a meddling superior alien force, I love that the ape-human-hominids may be dumb as a box of hammers but they are still inquisitive, and that inquisitiveness is tempered by scepticism. Fascinated but fearful. Then, of course, war-mongering capitalism is born and the biggest/smartest smacks the other males on the head, goes on to ravage all the womenfolk and start History.

The nature of the Human Beast then has seen us curious enough to drive innovation whilst sceptical enough to not rush headlong into acts of rampant stupidity too often. The two orbit each other in a fluctuating balance that has been encoded into our DNA over millennia.

So, to climbing; when I see my mates crowding around a shiny new bit of gear thoughts of the apes at the start of 2001 come flooding back to my mind. They descend hungry but unsure, clamouring to touch and turn the new curio over in their hands, sniffing it, probing it (and occasionally beating their chests).

For the past couple of months Vertical Life has been out and about using Black Diamond’s shiny new RockLock Magnetron locking ‘biner (the only one in the country no less). The Magnetron is BD’s purported paradigm-busting piece of kit that does away with screw and twist-locking mechanisms in favour of magnets as a way of securing the gate of the ‘biner shut. It’s touted as removing the need to make things complicated to make them secure.

Wherever we have pulled the Magnetron out, be it at The Arapiles, in The Blueys, at The gym or around a campfire in The Gramps, people’s reactions have always followed the same trajectory: fascination makes way for wariness, which quickly builds into an attempt to identify potential points of failure, which is rendered into a brief – often heated – quasi-scientific discussion that tapers into stoney acceptance accompanied by covetous glances a la Smeagol.

It makes for great crag crap-talking and the most interesting part is the scramble to identify potential points of failure. The list generally includes some or all of the following, in no particular order:

Neither rain, nor snow, nor sleet, nor hail…

1. Water
In Victoria it rains a fair bit – or at least lately – I climbed with it in the rain and water had no effect on the magnets (although who climbs in the rain apart from idiots… and mountaineers?). I also tested it in a lab (okay, it was my shower aka the rain simulator) and the mechanism was not compromised at all.

Magnetron (and by default Simon’s life) – 1. Haters – nil

2. Rope-induced accidental opening
I stood in my harness in my lounge room for a considerable amount of time (not uncommon in itself) trying to get the rope to loop around the ‘biner, simultaneously constrict the two locking arms and force the gate open. Couldn’t do it.

Magnetron – 2. Haters – nil

3. General non-specific over-engineering
This is always a strange one and could be less of a reflection of the level of engineering and more of the speakers’ innate fear of the new. We all claim to want a novel and exciting life, but we often rush to the comforting embrace of the familiar like whimpering children or redpointers. The Magnetron is pretty simple, it doesn’t have any springs – when the gate is open the magnets repel each other to keep the arms open, when you close the gate the magnets are attracted to the steel and the arms are held by the catch. Easy as.

Magnetron – 3. Haters – nil

Like sands through the hourglass…

4. Dirt and general filth

I simulated general-use contact with sand, finer-particle dirt, and mud. Surface crud had no effect, but after I buried it in the sand at the base of Amnesty Wall and then tramped on the ground above it, the mechanism did gum up, stopping it from opening – hardly general use. However, the sand was easily cleared with a few taps on a rock and normal functioning resumed.

Magnetron – 4. Haters – nil. (Caveat: don’t bury in sand, idiot.)


5. Foreign body interaction
We tried to disrupt the magnets with other magnets and metal objects, but we found it very hard to obstruct normal use. Some of our more sordid mates hypothesised a possible negative interaction with a Prince Albert or a clit piercing. Alas, we were unable to test for this potentiality ourselves, so we can neither confirm nor deny this. (We’d be happy to hear from anyone so marked if they were keen to undertake some experimentation.)

Magnetron – 5. Haters – nil

Goodbye magnetism

6. Massive failure of magnetism
We are not sure but perhaps a catastrophic realignment of the Earth’s magnetic field – which flips on average every 500,000 years, in case you didn’t know – or the widespread reversal of the fundamental laws of physics could cause the magnets in Magnetron to become inert lumps of metal. It’s possible. But if The Apocalypse comes who will care about the potential failure of their locking ‘biners? No one. There’s probably more chance of evil X-Men villain Magneto turning up and using his mutant power to disrupt your Magnetron or perhaps a stampy Godzilla crushing you to death on the approach walk.

Magnetron – 6. Haters (and associated super villains/monsters) – nil

7. Human error
Yup, people make mistakes. And stupid people make the lion’s share of them. Don’t be stupid. Is your stupidity Magnetron’s fault. No.

Grand total of test: Magnetron – 7. Haters – nil

Overall, in field testing I found that the Magnetron’s action to be smooth and simple; it’s light and strong; it can be operated easily with one hand; and is the same whether you use right or the left – perfect for southpaws who struggle in a world full of right-hand-bias. Like all your climbing gear you need to look after it so it can look after you when you balls are on the line. Is the Magnetron more likely to fall apart like a cheap Taiwanese suit than a traditional locking ‘biner, no – in fact, despite all the abuse and the clutching greedy hands it still operates like new.

In addition to my testing, the Magnetron has survived the Apes of 2001 obelisk test. The curious and cautious have cast their eyes upon it, held it in their hands, furrowed their brows, poked it with sticks and come up with not much.

If, like monarchists, you’re mantra is if-it-aint-broke-don’t-fix-it, then keep using what you’ve got. We at VL, good republicans all, dig the Magnetron. We will be embracing the new and boldly stepping into The Future.
Simon Madden

There is still no official Australian release date for the Magnetron though it is projected to be sometime in October, which if Black Diamond get their marketing right they could rebrand as RockLocktober. It will come in two iterations; the Gridlock for $42.95 and the Rocklock for $34.95.

For more information check out this little vid of the good people at BD giving their Magnetron spiel:

Contact Sea to Summit ( for more information on 1800 787 677

14 thoughts on “Review: Black Diamond Magnetron

  1. Ben

    This fascinated the shit out of me to be frank. Magnets! Brilliant.

    I still don’t understand why having two of this device next to each other might not have some deleterious effect, it felt like the author skimmed over that a little quickly, but I am also a staunch republican so if I ever climb, it will be with magnets.

    1. AdventureTypes Post author

      Hey Ben, it’s a trick! There was really only one Magnetron. Maybe having two too close is one too many. We did not test for this happenstance but will include it in follow up field testing.
      Until then may your magnets always attract.

    1. John

      My iPad has a cover attached with a large magnet – no problem apparently. It seems unlikely that a steady magnetic field should affect electronics.

  2. Chase Berman

    My friend bought one of these when they first came out some months ago and now it wont stay closed as well on one of the magnet arms. Did you find that out too or is this an isolated incident?

  3. Lenny

    I have been curious about this, and do not have one yet to try. I love the concept, but hate the fact that it makes good climbers lazy, and in a case where they go back to screw gates, might forget to check those gates.
    Anyway, my question is related to ice climbing. The Magnetron uses indents in the head of the biner for the locking arms to catch. Is it possible for those indents to become full of water, then freeze. The locking arms may not be able to close completely? Although, I understand, it would be hard for ice to form as the biner is normally closed, could it be a possibility?

    1. AdventureTypes Post author

      Hi Lenny,

      Down here at the Arse End Of The World (Australia) there is not a massive amount of ice climbing to be had so we have not put ours through its paces in ultra-cold environments so can’t speak to the propensity for ice build up to affect function.

      And as for your first point, user error is probably the number one source of all climbing-related calamities. Yes, you’re right one of the considerations of climbing gear engineering should be the mitigation of the risk of human error but the onus is on the individual to be familiar with their gear and take responsibility for appropriate use. See our other piece about carelessness here:

  4. Martin

    There really is only one thing that has me concerned. Magnets tend to lose their magneticity or whats-it-called, when they get too hot (like in a car parked in the summer sun) or when they get smashed against something (or each other) too often, like when the biner snaps shut or gets bashed against a rock by accident. I think there needs to be a long-time test run for those things (or has there been one already?).

  5. Adrian

    I bought a Gridlock Magnetron to try out as a belay biner when they were on sale. I think I used it for one session at the gym before reverting back to my screwgate Gridlock. It’s so damn fiddly having to open it three separate times to thread your belay device onto your harness loop. The alternative is trying to hold it open while manouvering everything into place in one go and that’s just as annoying to do. The standard screwgate Gridlock is way easier because you can just push it open without having to fight with the tiny magnet catches every damn time.
    Wish I had bought a standard Magnetron to try out. I can see it being a handy piece of kit. Definitely wouldn’t recommend the Magnetron Gridlock though.


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