CT Lightsaber is suppose to cut through anything but not Darth Vader's shoulder?

During Luke Skywalker's Light saber duel against Darth Vader we see that Luke manages to strike Darth Vader's shoulder with his Light saber but nothing cuts though. I thought a Light saber can cut through anything i'm really confused guys.

 

I think it was a light hit. I believe I had heard there was some Sith sorcery on Vader's armor, but I'm probably mistaken. It's probably the former. I presume they didn't have the technology back then to show that he had been injured. Vader did, after all, cry out in vexation and quickly end the duel by severing Luke's hand.

 

I remember when I was a kid, we used to argue if a lightsaber could cut through Superman.

 

"Negative, negative; it didn't go in! Just impacted on the surface."

 

It was a glancing blow, watch closely.

 

It could have just been a light tap, but my personal interpretation has been that Vader's armour was lined with some lightsaber-resistant material such as cortosis

 

"This is for Kanan, Vader!" It was merely a light hit. It was a turning point in the fight, because Vader loses his cool and goes all out afterwards. Luke's hand is cut off mere seconds after he slashes Vader's shoulder.

 

Love that detail. Proves that Luke's skill with a saber is a pebble compared to the massive boulder of Vader's skill

 

It was a "back door" program Anakin built into his lightsaber so it could never be used against him.

 

Just before Luke strikes a glancing blow on Vader, Vader swings and misses and hits the rail with his lightsaber. Doesn't cut through it. I think it's one of those little quirks of the movies.

 

Definitely meant to be a glancing blow. Honestly, I doubt Luke expected to make the hit, and probably was already prepared to swing back the moment he made contact with the armor. The same thing happens when Vader strikes Kanan's pauldron during their duel on Lothal.

 

It was just a glancing bow. A lucky hit, really. Too bad he was fighting what amounted to a walking tank that now saw no reason to go easy on him anymore.

 

But Vader reacted with what sounded like an expression of pain. The fact that we don't see any signs of armor damage, next, might be an indication for self-repairing armor, IMHO.

 

he has armor.. and robot arms.
he did make a pain noise when hit there.
if his shoulder was badly damaged he could just get it fixed.
it was a glancing blow but he may have been burned.

 

It was obviously Palpatine.

 

Just a glancing blow.

 

first time I've ever heard the term "glancing blow"

and several people use it at once,

allow me to come up with an alternative

it was "a light tap" that caused sparks...like light taps do...

 

It was a weak and lucky strike in that duel, but it was enough for Vader to take off the kiddie gloves and end the fight in seconds.

 

What do you think his armor is made from? It's not worth much if you can simply slice through with a saber. I'm betting you can't easily get past the helmet either.

Spoiler

In a new TFA trailer you can see Finn fight a riot trooper equipped with a shield and Finn's lightsaber doesn't seem to cut through either.

 

It's as if the filmmakers didn't even watch the Prequels when making the Original Trilogy.

 

^ Cue Dark Helmet watching the Spaceballs video. "Just fast forward past that bit."

 

As much as I really like the Vader construction scene in RotS, I always assume DV was put into the set of armor to keep him alive and functional, but that he continued to tinker, adjust, and improve it/himself throughout the rest of his life. I mean, this is the kid who puts together a functional protocol droid and race-winning pod racer when he's like 10 years old. I firmly believe this is a big part of the payoff of all this groundwork set up in I and II, of Anakin being so good with mechanics. I get the decision at the end of RotS to have DV put into the exact suit we know (smooths narrative clarity), but I would have been happy if this suit had been more rudimentary, still recognizable but not yet "complete." I still think he was changing his suit throughout III--VI, though, even though it looks extremely similar.

This said, I bet he took every opportunity to include protection, including from lightsabers, as I'm sure he wants nothing more than to duel and cut down lightsaber-weilding opponents, into his armor. He does give a sort of grunt of surprise/pain at the glancing blow, and though we don't know about exact extent of his post-Mustafar injuries he still has his physical, un-replaced right shoulder, as far as I know.

 

His armor and helmet look slightly differently in every movie which I explain to myself with his constant tinkering. I believe he was actually made a competent mechanic in the prequels because he becomes half machine later. *insert Lucas logic about themes and rhymes whatever*

 

Before RotS, I had always assumed that he had a long, slow recuperation in a hospital bed and passed the time by designing his own armor/life support suit. I prefer that he chose his own armored look, as opposed to having Sheev just pick a suit off the rack to fit him.

 

Indeed. I thought the same thing.