Visual Design Puns

So I work at a company that manufactures steel bolts, nuts, washers, anchor/bent bolts, rebar, chains etc. and I'm trying to come up with a t-shirt design for the holiday season. I have the visuals that I want down (a snowflake made out of nuts) but because it's going to be a more fun design ths I've been trying to think of a little pun that I could put across the back, and I'm coming up short.

If it helps we do a lot of forging, pointing, threading, cutting and shipping. We work with steel (and hardened steel) 90% of the time. My workplace is pretty casual so don't feel the need to keep it PG.