Chapter Text
“Just a few more minutes.” Stark mumbled from behind his computer screen. He must’ve sensed how antsy Bucky was getting. He’d been trying his best to sit still for almost an hour now, with wires coming out of his metallic arm, all hooked up and leading to Tony’s computer. Bucky watched the other man typing away, completely focused on the job at hand, occasionally looking over to poke or prod the arm still attached to him.
Bucky let out a small sigh. A few more minutes could mean forever when it came to this guy, so he pulled out his phone and texted Sam to see what he was up to.
B: Where you at?
He stared at his screen and almost immediately got a response.
S: Downstairs gym. Need backup?
Bucky pursed his lips, hiding a small smile at Sam’s offer. He knew that Bucky never came to Stark’s lab alone - usually he had Steve or Sam as a buffer. But Bucky figured that if he was coming down to get upgrades done to his arm, he could face any awkwardness that might arise. Thankfully, though, it seemed that Stark wasn’t holding any grudges, if anything he was indifferent, more interested in the arm than anything he might have to say, and Bucky was happy to sit in companionable silence and let him work.
B: Nah. Almost done here I think.
Stark did finally seem to be finishing up. He unplugged the wires from his arm, and closed him back up, giving him a pat on the shoulder.
“Alright. I think we’re set. Wanna give it a test run?” Tony held up a screwdriver.
“What, you gonna stab me with that?” Bucky joked, hoping to ease some of the tension. Stark just chuckled under his breath and tapped him lightly on the forearm, the clang of metal against metal echoing in the wide space of the lab.
“Feel that?” Stark asked. Bucky nodded. “Okay. I’m going to try with something soft now. Close your eyes.” Bucky furrowed his eyebrows and frowned, and Stark laughed at that. “Just need to make sure you’re not picking up extra stimulus from sounds or vision. I won’t feel you up, promise.” Bucky hadn’t noticed that he was tense, but he forced himself to relax, and closed his eyes. He felt a finger softly run up his inner elbow, it was almost ticklish. He jerked away on reflex, eyes shooting open.
“Sorry.” He said. Tony just waved it off.
“No, no that’s good. You can feel small touches like that, means I haven’t broken anything. I think it should be working then, but let’s try with something bigger.” Tony turned around, looking for something else on his workbench.
So it was working. That was a huge relief. Bucky had come to Tony in desperation a few weeks ago, after a big battle left his arm in a state of constant pain. Tony fixed it right away then, it seemed a pain receptor had just gotten crushed when a tractor - yes, a fucking tractor - landed on him. After Tony fixed it, he kept digging around inside the arm, and had told Bucky that he could probably make it so that he wouldn’t feel pain like that next time he was in battle. Bucky had quickly agreed to let Stark give it a try. Now here they were, and it seemed Stark held true to his word.
“See - the original Hydra design amplified pain so you know when someone is attacking you on your left. Pain is a great defense mechanism, it lets you know if something is hurting you, and tells your brain to move away. But the pain itself isn’t necessary as an alarm, so I’ve circumvented that altogether.” Tony casually chatted as he held up a blowtorch. Bucky held his breath. What the hell was Stark going to do with that?
“Relax. Just want to make sure you feel heat. Stopped smoking back in 95’, and I couldn’t find a match - this is all I have down here.” He turned the torch on, and held it up to Bucky at a safe distance. Bucky reached over and felt the warm air surrounding the blue flame. He nodded again.
“Good.” Tony confirmed. “Now...could you get a little closer? Just enough to see if you feel any pain?” Bucky steeled himself. Of course, he would need to test it to make sure it could actually prevent pain. He inched closer to the flame, probably closer than would be safe with his human hand, but was surprised when, instead of a scalding burn, he just felt a slightly hot buzzing sensation running up his arm. It felt strange, but not necessarily painful. He pulled back, not exactly liking the feeling.
“That was...weird.” He examined his hand. It wasn’t scorched, but he could tell from the color of the metal that it was burning hot, even if he couldn’t exactly feel it. “It feels like bees walking around on my hand.”
“Yep, that’s the workaround.” Stark explained. “After a certain threshold - instead of feeling pain, you’ll feel that tingling, to let you know something’s happening.” He picked the screwdriver back up, and started hammering on his bicep with the blunt end, presumably to show how it worked. Bucky didn’t feel anything more than the slight buzzing, he was actually getting used to it now. “See? It’ll even work so you don’t feel pain when you’re removing and re-attaching it. Even if some baddie decides to rip it off, you won’t feel much.” He proudly yelled through the loud clanging. Bucky put his other hand out, plucking the screwdriver from the energetic engineer.
“Thanks. It’s not a punching bag, you know.” He reminded him. “You’re lucky you didn’t leave a mark.” He threatened him dryly, without bite. Stark just grinned, and waved him off.
“Well, go on, take it for a drive. Let me know if anything bugs you.”
He headed straight for the gym.
“Think fast.” He called out as he chucked a bottle of water to Sam. Sam turned and caught it, gratefully taking a swig before addressing him.
“You got your upgrades?” He asked. Bucky liked that Sam kept up with his day-to-day events, even if they were more hum-drum than usual. It gave him someone to talk to, when he had no one for so long.
“Yep.” Bucky shifted his metal arm towards him, extending it out for Sam to see. “Hit me.”
“What?” Sam eyed him cautiously.
“Hit me. As hard as you can.”
“You want me to hit your metal arm with my regular-ass hand? No thanks.” Sam ignored him, opting to take another sip of water instead.
“Come on. Just wanna show you it works.” Bucky looked around, and saw the sports equipment tucked into a corner. He jogged over and pulled out a baseball bat, enthusiastically handing it to Sam. “Hit me.”
“Man, no way.” Sam refused to take it.
“If you don’t, I’ll call Steve down to do it.” Bucky warned. He knew Sam would have no choice but to agree - Steve never held back when it came to testing the limits of his boyfriend’s technology. Sam frowned, but ultimately grabbed the bat in frustration.
“Fine. Only cuz’ I know Steve’ll make us do a whole sparring session if you call him down, and I’m trying to get to lunch on time today. I’m starving.” Sam reluctantly swung the bat with one back-handed arm, keeping his grip loose, the bat clattered lamely against his bicep.
“Oh, give me a break. That wouldn’t even hurt a kid . Swing like you mean it.” Bucky egged him on.
“You asked for it.” Sam finally put down his water bottle and got into batting position. Bucky held out his arm gleefully, and barely felt anything when the bat cracked against his forearm, splitting in two. Sam’s eyes widened in fear, and he reached out to help - but Bucky, thrilled with the outcome like he’d found a new toy, just laughed in delight.
“See?? I didn’t feel a thing!” Bucky excitedly announced. “Hit me again!”
“I think I get it.” Sam nervously chuckled. “I’d rather Steve didn’t walk in here to catch me wailing on his best friend’s arm. Let’s go grab lunch, huh?”
Bucky huffed, annoyed that he couldn’t keep playing with his newfound ability, but ultimately, his stomach growled louder than he could hide, and he agreed, turning back around toward the door. “You’re buying.”
“Of course.” Sam rolled his eyes and jogged to catch up to him. “But let me go shower first. Meet you in a minute.” Before Sam broke away towards the showers, he felt a few fingers quickly brush against his forearm - just once. He didn’t look back, just chuckled under his breath. Sam - such a worrywart. Probably still felt bad for hitting him. Bucky walked out to the front of the tower where he knew Sam would come find him after getting cleaned up - it was a nice day to sit in the sun.