The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

The New Hotness

  • Mailbox Door Rebuild

    The flanges around the door of our giant mailbox rusted through, leaving the door to bend along the embossed (debossed? Whatever) lines across the front. Eventually, the bend got bad enough to keep the door from latching closed, but reviews of the current crop of mailboxes suggest they’re even more prone to rusting after even fewer years.

    Well, I can fix that:

    Mailbox door rebuild - installed
    Mailbox door rebuild – installed

    Because the bottom third of the door, basically everything around and below that horizontal ridge, had corroded, the general idea was to stiffen it with an internal plate:

    Mailbox door rebuild - interior
    Mailbox door rebuild – interior

    The array of small holes suggest the plate’s rich lived experience. Some are even tapped!

    External angle brackets stiffen the sides along the corroded flanges and surround the equally corroded pivot holes:

    Mailbox door rebuild - exterior
    Mailbox door rebuild – exterior

    The term “brick shithouse” springs unbidden to mind, doesn’t it? Those spare holes come from previous uses; I decided this application didn’t demand cosmetic perfection and, as a result, the remaining angle stock has no holes at all.

    Also, the angle brackets are as long as they are because that’s the maximum throat depth for Tiny Bandsaw™. I splurged on a Proxxon 10-14 TPI blade (for future reference: PN 28172) that cuts aluminum like butter, much better than the stock 14 TPI blade.

    The hinge pins used to be rivets. After careful consideration, I replaced them with 1/4-20 button-head cap screws:

    Mailbox door rebuild - hinge detail
    Mailbox door rebuild – hinge detail

    Yes, the sheet metal now pivots on screw threads, rather than a nice smooth cylinder. The nyloc nut maintains the proper amount of looseness around the battered sheet metal.

    While I had the door open, I slobbered hot melt glue over the flag anchor, which should keep it from spitting the ratchet pin into the roadside debris ever again:

    Mailbox door rebuild - flag anchor
    Mailbox door rebuild – flag anchor

    A pleasant evening of Quality Shop Time, indeed!

    The alert reader will note I’m securing aluminum plates with stainless steel hardware on a (nominally) galvanized steel box, thereby forming several batteries with a brine electrolyte from wintertime road salt. My engineering judgement determined this repair will last Long Enough™ and, most likely, succumb to somebody not quite making the curve while accelerating from the traffic signal.

    Aaaaand those painted numbers still look pretty good after four years.