This...is...Brilliant, I'd seen some attempts at making blast doors but this is the most perfect I've seen so far, they actually work, great work with those gears, especially the ones spinning inside your brain, great job!
Holy moly. This is genius. I actually thought of making one of these before, but I didn't even thought of making an opening mechanism. And Typh, I believe this is quite simple of making. You don't need instructions. Goo job Cole.