EZ Grip Friction Drops are a miracle product. I use them on stripped screws or even just stubborn ones where I can't seem to get a good grip and the screwdriver keeps slipping.
EZ Grip is what I’ve used before but, it’s kind of expensive on Amazon.
6 point wrench or socket. Extension to get more torque. To avoid rounding it off, use a friction modifier, like valve ground compound or ezgrip: EZ Grip Friction Drops, Aircraft Grade EZ59183 https://www.amazon.com/dp/B00BFEJY5W/ref=cm_sw_r_apan_glt_i_RJEVKNGQ5PGEYB14XNYJ This stuff increases the friction 10x and works like a charm.
There is a compound, called ezgrip, that increases the friction 10 times (!!!). In a pinch, use valve ground compound to increase friction. It is a live saver for every mechanic:EZ Grip Friction Drops, Aircraft Grade EZ59183 https://www.amazon.com/dp/B00BFEJY5W/ref=cm_sw_r_apan_glt_i_9FJ5WSAK73JAAHENMJBZ I use ot on Alan's, her, even philips heads, try it and be amazed!
If you get the Allen head or Torx, I highly recommend a quality set of Allen keys or Torx bits. Also buy yourself a bottle of EZ Grip. Will def save you from getting striped screw heads. And its handy to have in your tool box for removing stuck screws in general.
https://www.amazon.com/Aircraft-Screw-fastener-Removal-Friction-Drops/dp/B00BFEJY5W
Get it on there tight. You will hopefully need to hit it with a hammer/mallet. If not, go one size down.
I've been in your situation before (many times lol) and was recommended this stuff but never ordered it. Just FYI.
I've met very few fasteners that couldn't be pulled out with EZ Grip. We use it on Tridair fasteners (that have a countersunk Allen socket head) when they round out. It should be even more effective on rounded out square head screws.
You could try some of this stuff. Assuming it's not completely rounded off. It's worked well for me in the past. It's like a sand paste which helps restore some of the grip.
I've seen a trick with putting a rubber band between the screw driver and the screw. I've never gotten that to work though.
I work on helicopters and they use a lot of aluminum screws because they are strong enough but lightweight. The only thing is they are softer than other metal and strip super easy. I've been using EZ Grip for 4 years now and it's never let me down. http://www.amazon.com/Aircraft-Screw-fastener-Removal-Friction-Drops/dp/B00BFEJY5W
Get some scouring powder (like Ajax). Get the end of your screwdriver wet and dip it in the Ajax. Remove the screw. Alternately, use this:
https://www.amazon.com/Aircraft-Screw-fastener-Removal-Friction-Drops/dp/B00BFEJY5W
If things are getting spicy with a stripped fastener/bolt, turn to EZ Grip. Buy a bottle, it will last you a decade if you're a DIY'r. It's basically a suspension of very sharp metal bits that increases the bite of your wrench/socket by orders of magnitude.
Very popular in military aviation where hundreds of fasteners are used to secure aircraft panels. Buy a bottle - your bowling score will go up, and your golf score will go down.
https://www.amazon.com/Aircraft-Screw-fastener-Removal-Friction-Drops/dp/B00BFEJY5W
EZ Grip Friction Drops, Aircraft Grade EZ59183 https://www.amazon.com/dp/B00BFEJY5W/ref=cm_sw_r_apan_i_CCJFMYPNJMCD9K8SW7WH?_encoding=UTF8&psc=1
Works like magic 🎩
EZ Grip Friction Drops, Aircraft Grade EZ59183 https://www.amazon.com/dp/B00BFEJY5W/ref=cm_sw_r_cp_api_i_8ZZ0TXZ69PPFEKN37287?_encoding=UTF8&psc=1
EZ Grip Friction Drops, Aircraft Grade EZ59183 https://www.amazon.com/dp/B00BFEJY5W/ref=cm_sw_r_apan_i_RB6EAPY7ATDCZ7EY5CCG
I'm USAF. We use this to get stuck screws off of aircraft. THIS SHIT IS MAGIC. Read reviews.
EZ Grip Friction Drops, Aircraft Grade EZ59183 https://www.amazon.com/dp/B00BFEJY5W/ref=cm_sw_r_cp_apan_glt_fabc_WE92YDNX8TXE1N6835E9?_encoding=UTF8&psc=1
Try ez-grip instead
https://www.amazon.com/dp/B00BFEJY5W/ref=cm_sw_r_cp_apa_fabc_cOv7Fb6SQATY9
Get some sand and oil. Mix it up and stick it in the screw hole. It makes a mixture like EZ Grip
Or this stuff. It says aircraft, but it can obviously be used for other applications.