Kirk Hammett used to get so "frustrated" with writer's block, he would want to "smash his guitar" to pieces.

The Metallica axe-slayer no longer gets "stuck" because he has learned to just "grab what you can in the moment" and not focus on the past or future, but that wasn't always the case.

Asked how he deals with writer's block, he told Total Guitar magazine: "Don't think about the past or what has been done. Don't think about the future and what you need to do. Just see what you can grab in the moment. That's how I write music, and it has turned me into a more prolific composer because I don't get stuck like I used to. I used to get writing blocks for months and months and months, and not write a riff for months, and get frustrated about it, and think about smashing my guitar. That doesn't happen anymore."

Kirk also insisted he doesn't get bothered by criticism, because if they "sucked" that bad, they wouldn't be selling out stadiums.

He said: "My attitude is that if you're out there and you're touring, and you're making albums, and you're recording, there is no way you suck. And so I can't stop being bewildered by all these people who say, 'This guy sucks! That guy sucks!' Hey, I've got news for you - you don't get to where you're at if you f****** suck! Okay? These people are talking on 10 per cent of what they see in all of these people musically. It's incredible. I don't think anyone really sucks. These days, I don't think bad guitar solos even exist anymore because everyone is just so much better than they used to be. Like, in the '60s there were bad guitar solos. You would find them in pop songs, where you'd go, 'Urgh! Nice try. Next!' But that's the past, and that's a good thing."