There's nothing wrong with trying fix or make something yourself, but it's worthwhile keeping safety at the forefront, even when you're building a gigantic mechanical death spider.
That rather unlikely scenario was what Mythbuster's Build Team Member Grant Imahara was up to when, apparently, he very nearly came to a rather squishy end.
"It's nearly crushed me several times... working on it late at night in my shop" he notes in the video interview.
In a piece for MAKE magazine, Imahara goes on to note that this wasn't the best idea:
PRO TIP: Don’t do what I did. Never work alone around heavy or otherwise dangerous equipment.
Wise words indeed, whether you're working on cyber-arachnids or not. If you're not around to Do It (whatever "It" might be) because you've stopped being "Yourself", then all your DIY plans will be for nothing.