The Slide part on Iron man by Black sabbath feels impossible

[u/KRYPTEX101]

Hey, so i recently got a acoustic guitar and started learning this song but the part where you slide from 10-12 to 9-11 3 times feels impossible, i've been trying for days already and i have seen some success on the A string but the D string just always gets muted no matter what i do, even when i practice the strings individually the D is almost impossible. Any Tips?

[u/Budget_Map_6020]

Recording footage of you trying to play it for custom feedback will likely be a more productive and less time consuming process for both the people giving advice, and you reading them.

My educated guess, based on what usually occurs, is that your thumb position is off, you might be pressing too hard with your fingers on the strings, or even squeezing the fretboard (tension is the enemy of form and fluidity). So posture and relaxation are where you should start troubleshooting.

But seeing a performance is the way to go for advice.

[u/LZoSoFR]

It's basically a speed game, and you increase speed by challenging your muscles and brain each time more and more.

What I'd do: Break apart the sliding elements and practice them from level 0 until level IRON MAN. To me it should look like this:

Slide only with your first finger on the difficult parts. Start with a slow speed and focus on leaving as little space as possible between the notes.

Then practice the same difficult part with your ring or pinky, whichever is comfortable for the fifth of the power chord.

Then speed it up for each individual finger.

Then build up the speed with a full power chord

[u/PupDiogenes → u/LZoSoFR]

Great answer that I want to add something to: consistent hand position. Your thumb slides the same distance your fingers do as they do it.

I've seen it over and over. People learning that riff get to the 10 9 10 9 10 part and they try to plant their thumb in the same position for it. The thumb needs to move up and down the distance of a fret.

[u/JstASkeleton]

Without knowing anything else, clip your nails.

[u/PupDiogenes]

You're already doing the right thing by practicing both fingers separately. If each finger can't do their part on their own, they'll never be able to do it together.

Keep working on that one fret third finger slide. Make sure your hand, while relaxed, stays frozen in position. If your finger needs to slide down one fret, that means your thumb needs to slide down the distance of one fret to keep your hand position consistent. It shouldn't be your fingers or your hand driving the slide, but your arm.

Your finger keeps the pressure (not too much) and your thumb executes the slide. Do this, and you'll get it right away.

[u/lborl]

how high is the action on that guitar?