Geri Sullivan, Girl Homeowner: Mailbox Saga (continued)

Mailbox Bolt Collage

They're bolts. Thanks to a link from David Levine, I know they're either SAE J429, Grade 8 or ASTM A354, Grade BD bolts. Complete with an extra cute little triangle in their markings. Unless the triangle makes them something altogether different in the bolt world, that is. There aren't any little triangles on any of the grade markings shown at the American Fastener website.

These bolts hold a wooden board to the cast iron plate at the top of my mailbox pole. The whole thing looks homemade...by a Tool Guy whose mailbox had been vandalized, I'd bet. The bolts are made of medium carbon alloy steel or plain alloy steel, "quenched and tempered." Their strength properties are 25-41% greater than high strength structural bolts and 2-3 times greater than standard, everyday bolts. They're serious overkill for the job of holding a 5/8" thick piece of plywood 6" wide and 17-3/8" long to a piece of iron. Tool Guy used six of them. ( Further mailbox natter within, including a small design project with fannish amusement value )

Yes, I'll post a snapshot or two of the new box, complete with its two doors, spiff interior sign, and other details as soon as it stops raining and I finish installing it.