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Interview - 018 - Carl-August Mertz

Finally I got this interview back from my friend Kalli (yes, Kalli is his nickname - Kalli with a "K" - remember this). Prepare for a long and great interview with very interesting insights from this bending machine.

First I go back to the year 2015 - in this year I started with small steps my own bending journey, i found the youtube channel from Kalli and was super impressed from all the bending feats he has done till that date.

In 2016 I was ready for my Ironmind red nail certification and mailed in the typical way to Ironmind. I was expecting that I had to do the cert at Hermann Korte, because every german cert was done at his place and he was the official reseller of ironmind products in germany. But in this year Hermann quit his business and for my surprise Iromind told me that my referee is Carl-August Mertz.

Another surprise was that Kalli only lives 1,5 hours by car from me.

So first touch with Kalli was via mail and then we met each other for my red cert at his garden. This was a great day, we understood each other directly and had a lot of fun. Did the cert and then Kalli showed me how to bend horseshoes, after all we had a small barbecue and closed the day with great feelings.

This was the beginning of lots of other meetings which are always a highlight for me, because Kalli is always surprising with some great and very strong feats. No matter if it´s bending or grip stuff, he did it - and always with style!

That goes so far that now Kalli can´t surprise me with new feats. When he has done something extreme, I am always thinking: ok, cool, strong, but no surprise, because

it´s Kalli. He is one of the strongest guys I ever met in person.

We stay in daily contact and it´s always fun, no matter if it´s about bending, grip, strength, climbing, other sports or family things.

The only thing that bothers me, is that I can´t drink a good old german beer with this buddy, because he is making it the right way and don´t drink any alcohol. It seems that I have to accept it, but I hate it.

Thanks Kalli for sending me the interview and up to many fun and strong years together in the future.

Take a look over his great stuff here:

Now enjoy the interview:


Carl-August „Kalli“ Mertz

Year of birth:




Weight 108kg


Germany - near Frankfurt am Main


Teacher (PE, Chemistry)

Relationship Status:

Married with 2 kids

Question 01:

What does steel bending mean to you?

It’s a test! A test of your physical and mental abilities. You bend steel, that is not made to be bent! It is not only a test of how strong you are, but a test if you are smart enough to find the best positions for your body to apply the most power on the steel and it’s a test of your will and how much pain you can handle! It’s a test of how to overcome obstacles.

Question 02:

When and why did you start steel bending and what does or did your active time look like?

2012 I bought some Captain-of-Crush grippers after the warm-up gripper I used before my bouldering sessions broke. On their homepage I found the nail bending section and was curious…

So I went to the hardware store and bought some nails… et voila… I was full in! I ordered IronMind’s „Bag of Nails“ and a couple of months later I certed the Red Nail. I was the second man after Tommy Jennings to cert all three Reds in one minute.

In 2013 I started bending FBBC steel. This was a really good time with all the different options to cert! They went out of business a short time after and as I had no more goals to go for, I dropped short steel bending. (I had worked on the Gold for quite some time, but my shoulders had trouble with the length. I could crush a prekinked one from 7“ in about 12 or 15 seconds, but couldn’t get it started from 8“.) So after FBBC was off, there were no goals left to aim for… They have a new owner now and they sell steel, but the certification is dead. A lot of guys were on fire, when FBBC was back, including me, but you had to wait a couple of months (up to one and a half years) for the confirmation of your cert and it was later canceled at all. It’s a shame that the new owner doesn’t care about steel bending. He basically ruined a very important bit of steel bending history! So I haven’t trained any short steel bending the last couple of years, but was super happy to get the 8.8 Horrido-Cert!

Later (2016) I found my way to horseshoe bending, which was super addicting also! It was very confusing at the beginning, because I didn’t know where to start and how to progress. There was this progression list on Jedd Johnson’s (a grip athlete and author) homepage, but it was not systematic and totally useless for benders in Europe, because you can’t get most of the shoes over here. So I decided to create my own list and I dived really really deep in this whole subject! It was a great time! In 2017 I have bent over 120 different horseshoes (I PRed every session *lol*) and tried to sort them from easy to hard. (I posted it on Facebook and the gripboard, but Jan can post it here also, if there is the need for something like this!) I had a pretty good progress and made into the Worlds-Top-20 at the gripboard in a couple of months and to the Elite-Level on the IronGripWorld list. At some point I tried to cert a certain shoe for the gripboard. I failed like 7 or 8 times! Not the bend, but to video it! (Shoe out of frame, battery died, bad lighting at the measuring process, no memory card, bent in 3:15 instead of 3:00 minutes, you name it…) Clearly the Gods of Steel didn’t want me to cert that shoe. I did some harder shoes after that, but never bothered to video it or any other horseshoes since then. Despite that, horseshoes are still one of my favorites, till today I have bent 997 shoes. (Big thanks to „Strohm – Hufbeschlag“ and especially Kerstin and Kevin for the support over the last couple of years!)

In the end of 2017 I entered a grip competition and an event after the competition was the „Horst-Alldag-Memorial-Bend-Event“. Horst Alldag was a German steelbender and his signature bend was a 12mm x 54cm rebar bend over his head. None of us could do the over-the-head bend, but I was able to bend it freestyle and it felt so cool! That was my entry to long bar bending! I did some shorter braced bends before, but from that day on, I just wanted to bend BIG bars! At first I tried some other rebars, but then found David Hornes „Oldschool Braced Bending List“ and changed to HRS bars. In the beginning of 2018 I did my first „Goliath“ bar and it didn’t feel too hard. The „Goliath“ was originated by Eric Vining back in the day and is a standard in the braced bending world. (Watch Dennis Rogers „Dungeon Memories“ if you get the chance!) This was the moment when I realized, what is possible! Over the next couple of months I had a steady progress and did some bars no one else has done before me, the most important ones are:

Carl’s Colossus 12x50mm x 1,20m (1/2“ x 2“ x 47.2“)

Mega-Colossus 12x55mm x 1,20m (1/2“ x 2.165“ x 47.2“)

LEVIATHAN 12x60mm x 1,20m (1/2“ x 2 3/8“ x 47.2“) (Time limit: 10 minutes!)

Eckesachs 10x60mm x 1m (3/8“ x 2 3/8“ x 39.4“)

Balmung 10x70mm x 1,20m (3/8“ x 2 ¾“ x 47.2“)

And as important as my „firsts“ are the repeats of two classics for me: I was the first one to repeat the feats of bending a Wonder-Bar (Originated by Chris „Wonder“ Schoeck. – Check the documentation „Bending Steel“! Super inspiring!) - 3/8“ x 2“ x 30“ (10x50mm x 76,2cm) and a Yastrebov-Bar (first bent by Ivan Yastrebov), a 22mm round bar at 1,20m (7/8“ x 47,2“). Both bends I am super proud of!

That Chris performed the Wonder-Bar with his frame build is sooo amazing! I couldn’t do the two-hands-pull he did, because this bar is so short for me and the width of the bar makes a one-hand-pull super awkward, but nonetheless a super hardcore feat from him!

The 22mm (7/8“) round is just a MONSTER and was a highly coveted bar, which was tried by some of the „all-time-greats“ but got his first full bend from Ivan Yastrebov. With this bar he was on top of David’s „Monster Long Bar“ list, but I think this bar is a feat on it’s own, not only a placement in a ranking! For me (to repeat) a feat is way more important than a spot on a (world-)ranking list. Nothing wrong with ranking lists or competitions! I know that there are guys out there, who live for the competition and want to be „the best“. I highly respect that! But the only competition I run, is the competition against myself. I am super happy to bend and lift things in the realm of „the best“ (whatever that means), it doesn’t matter too much to me, if XY did a 20mm bar ½“ shorter or longer than I did.

Later I did some shorter 22mm bars, but as mentioned, they are not so important for me. To repeat Ivan’s original feat was important! To get a feeling for the performance he demonstrated before. My first 22mm bar took me nearly 45 minutes! But that wasn’t the feat he did! It took me a couple of months to repeat it IN STYLE and to do it in sub 5 minutes! #stylematters

For all my bends I applied the „Oldschool Braced Bending Rules“ established by David Horne (in cooperation with Pat Povilaitis as David told me), which were also used for the IronGripWorld cert (leather pads and rolled up towels or similar for protection and a time limit of 5 minutes. – Couldn’t bend the LEVIATHAN in 5, but under 10 minutes to be honest. But as I was the first one to bend such a bar, I was fine with it…)

The last two years I was more into grip feats and I could repeat a pretty long list of cool stuff (which I am super happy about) and add one or two new ones. But I started long bar bending earlier his year again and I am super motivated to bend big bars! Let’s see what this old man can do…

Question 03:

What do you love about steel bending?

Steel that is meant to withstand big forces bends to your will, how cool is that?!

Question 04:

What do you hate about steel bending?

Hm… Nothing! It is, what it is… Failure is just a part of the progress!

Question 05:

How does your training for steel bending look like?

I bend steel till I am tired and everything hurts. When the pain reliefs, I bend again.

Question 06:

How does your other training look like (strength or other)?

My other hobbies are bouldering/rock climbing (nothing beats a cold grippy day outside on the rocks), mountainbiking and grip training/grip feats! And I am super motivated to do a lot of other things at the same time. *lol* So sometimes it is hard to find a good balance (with family and work also!). And I am not a 75% guy. I am more like the 175% guy! (The running gag from a few years back: „Should I go high with volume or intensity?“ – „Do it like Carl: Go high volume on high intensity!“ *lol*) But this is a dangerous approach in a few aspects and not recommended. That’s the reason I alternate my training and shift my focus to one of my hobbies for a period of time (and I take some time off from one of the others). You can’t run high on intensity all the time! The time to recover is super important to avoid injuries and set backs. So for 2021 my focus will be on rock climbing and long bars.

Question 07:

What goals have you set for yourself?

At the moment I have some issues with my thigh, but I will be back! I have some projects left from 2 years ago. After I did the LEVIATHAN (12x60mm x 120cm S235 HRS – the hardest long bar ever bent) I had some good progress, but wasn’t able to finish some other bars. I hope to get them this summer.

And I have a bending challenge in mind. Some of you know, that I alternate my training to keep progressing and not to overload. So the last 2 years I was more into grip than bending and I completed a grip challenge, which I set to myself and dubbed it the C3D (Carl’s 3 Double Feats). I have something similar in mind for bending.

But first my leg needs to heal up and my DO needs some fine tuning.

Question 08:

What was the most impressive bend you ever saw (live or on video)?

There are a few worth mentioning:

Paul Knights Gold Nail bend! This video got me hooked with steel bending! The power he brought to the bar was mind blowing!

Ivan Yastrebov was the first man ever to bend a 22mm (7/8“) round bar! So for me a 22mm round bar is a Yastrebov-Bar! Super impressive and a big motivation for me to become the second man to bend one. His horseshoe bends are worldclass also!

Eric Milfelds horseshoe bends are super smooth, super hard and super inspiring.

Martin Kottes DO bends in my garage: SMOKED a Gold Nail in thin leathers and made a HKOAB look casual (and he finshed it to sub 2“!) and of course did not post it on Insta, Facebook or YouTube! Worldclass Underground!

Eric Vinings original „Goliath“ bend in Dennis Rogers „Dungeon Memories“ is poetry in motion!

Don Cummings all around abilitys are outstanding at the moment! Kirill and Reuben are well rounded also!

Tony Reid‘s (mindovermealart) scrolls are in a class of it’s own! This guy is a genius! An interview with him would be a great read!

Russian bending machine Alex Klimovich has lots of super impressive bends under his belt no one else has done! The 12.9 bolt, 10mm Square and a casual Gold Nail bend with brand new IMPs under cert conditions are otherworldly…

Question 09:

Rapid stuff – choose one

Bolts or steel?

Horrido Bolts

Unbraced or braced?

Braced (at the moment)

Singles or doubles?


Chalk or not?

Tons of chalk *lol*

Beer or water?

Water, as I don´t drink any alcohol...

Cordura or leather or both?


Short bars or long bars?

Long bars (at the moment)

Horseshoes or flat bars? Flat Bars (at the moment)

Chips or chocolate?


Question 10:

The last words belong to you. What do you want the reader take away? Let us know your poems of steel!

It’s not a poem, but my personal view on some topics:

1.) Feats are there to get repeated! If you want to repeat a feat, do it in the same fashion as the originator! If the originator did his bend in 3 minutes and you need 10 minutes, it is not the same feat! It can be a big achievement (for you or on the big scale) and you have every right to be proud of it, no doubt! But you have not repeated the feat! It is like lifting an INCH: Of course you can lift it with 2 hands, if you like. Nothing wrong with that. You can even call yourself an INCH-lifter, but you have not repeated the feat! Just keep going, put in more work and one day, you will be able to perform the same feat as the originator!

2.) I’ve read a discussion theses days where a performing strongman stated that, according to three well-known performing strongman, „a knee-kink isn’t legit“, because it is „too easy“! So if a bar is „too easy“ with a knee-kink, maybe you should start bending hard(er) bars!

3.) David Horne does an amazing job with the steel bending contests and ranking lists!

4.) Jan‘s certification system is the most consistent and reliable steel bending cert! Ever!

5.) Martin Kotte is a lazy rabbit!

6.) Martin Kotte said in his interview, that braced bending is cheating! BUUUUT: He has braced bent a Goliath! In my garden! And I have it on video! For only a 15 Dollar donation for the Horrido-Bending-Project I will send you the link to the video!

7.) Some self-proclaimed „strongman“ did and do amazing feats of strength! A whole lot of others are weak a.f.! „Performing strongman“ that STRUGGLE with 60D nails or have „worldrecords“, but get „outbend“ by random spectators on a show? WTF??? Don‘t get confused… That‘s the reason I don‘t call myself „strongman“. Imagine someone asking: „Oh! You do the same stuff like „ZZ“?“ – „NO!“

8.) Nothing great in life (or in sports) comes for free or is achieved without hard work, passion, blood, sweat and occasional tears! What’s the worth of something, that comes easy?

9.) Style matters!

10.) Go bend some steel!

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Martin Arjoon
Martin Arjoon
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This was an incredible and very enjoyable interview! I have admired Carl (CAMZ) for years and it was wonderful to read about his journey and thoughts! Thank you both very much! 🤙👊〰️👊🤙

Jan Horrido
Jan Horrido
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الرد على

Thanks Martin!

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