Re: Fasteners: Black Oxide or Zinc Plated?
 

If you have a local Fastenal, it's often a better option price-wise than the hardware store, if you're buying boxes of 100, which we always do. #10 and 1/4" are the ones we buy in varying lengths. #6 and #8 we cut to size.

And -- WRT the question -- black oxide.

Re: Fasteners: Black Oxide or Zinc Plated?
 

For 3309 who is based out of Anaheim, CA; it gets very humid at night when the fog rolls in. we always have steel parts rust. We have to paint steel right away to avoid rusting by the time events start. we have had black oxide rust out on screws we frequently had to take apart. But black looks nice, so we just replace a lot of screws. The 2012 and 2013 robots have rusting issues, 2013 can't run its climber anymore.

I am always surprised how much water we have to drain out of our robot's pneumatic system after practice. Even when we are machining parts inside we can see condensation form after we leave them on a table.

Re: Fasteners: Black Oxide or Zinc Plated?
 

More often than not, Black Oxide Fasteners win out over Zinc Plated for most FRC applications in my book. With that being said, outside of FRC, Zinc Plating, specifically Zinc Chromate, is my preferred choice.

That being said, if aesthetics are of concern, you really need to figure out if you robot is going to see ANY moisture during it's operating (when it needs to be pretty) life. If so, Black Oxide can be a bit annoying, since it'll show rust fairly quick, and Orange isn't exactly hard to see on Black...

There's also "Black Zinc", which is almost the best of both worlds, the aesthetics of black hardware, with the corrosion resistance of Zinc (usually better than "Clear Zinc/Regular Zinc) and depending on the exact process, as good or better than Zinc Chromate. ("Black Zinc" is often Zinc Chromate with additional Dye to darken the finish).... But it's not easy to find COTS hardware (reasonably priced) that's finished with Black Zinc, so unless you're willing to send a bunch of hardware to the plater, might be better off to forget about it.

Re: Fasteners: Black Oxide or Zinc Plated?
 

We are almost all Black Oxide because we primarily use, Thread-Locking Alloy Steel Socket Head Cap Screws from McMaster. They are a little more expensive than standard screws but we don't generally have to worry about them falling out. We do have a selection of standard Black Oxide bolts for prototyping.