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  • Fastener choices

    From Don Y@21:1/5 to All on Tue Feb 27 15:04:06 2024
    We're having a discussion re: choice of fasteners.
    The guy doing the bulk of the packaging design is
    advocating for screws: "It makes disassembly and
    reassembly easier".

    Well, yes, but disassembly is something that we
    rarely plan on doing -- which means REassembly is
    equally unlikely!

    So, then, it boils down to ASSEMBLY (and integrity
    of the bond).

    The devices are tiny -- nothing larger than one of
    those "jumbo packs" of "stick" gum (25 pieces??).
    Or, maybe a stack of 100 "quality" business cards.

    Being small, real estate is at a premium. So,
    fasteners need to be small.

    I've advocated for clamping the assembly from
    the outside -- a tight fitting (clam)shell that
    wraps around everything, holding everything in
    place as well as offering some protection to
    the assembly.

    [Any other fastener approach would similarly have
    to add some sort of "enclosure"]

    I can't imagine any sort of volume production using,
    e.g., M1.6s -- or smaller!

    And, I'm not keen on adhesives (or potting -- except
    as maybe otherwise required).

    This, of course, assumes you have more than a single
    PCB to "assemble"...

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jan Panteltje@21:1/5 to blockedofcourse@foo.invalid on Wed Feb 28 06:11:49 2024
    On a sunny day (Tue, 27 Feb 2024 15:04:06 -0700) it happened Don Y <blockedofcourse@foo.invalid> wrote in <urlm8m$3e933$1@dont-email.me>:

    We're having a discussion re: choice of fasteners.
    The guy doing the bulk of the packaging design is
    advocating for screws: "It makes disassembly and
    reassembly easier".

    There are law for repairability

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From John Robertson@21:1/5 to All on Tue Feb 27 22:59:56 2024
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    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Don Y@21:1/5 to John Robertson on Wed Feb 28 09:57:23 2024
    On 2/27/2024 11:59 PM, John Robertson wrote:
    On 2024/02/27 2:04 p.m., Don Y wrote:
    We're having a discussion re: choice of fasteners.
    The guy doing the bulk of the packaging design is
    advocating for screws:  "It makes disassembly and
    reassembly easier".

    If I had a vote, I say make it easy to take apart as something will go wrong -
    sooner or later. Unless this is meant to be tossed when it dies!

    But what do you think YOU can do to fix that "wrong"?
    The boards are tiny, chock full of BGAs and 0201 RPAKs, etc.
    Can you even *probe* these parts?

    Disk drives fail; how often do you *repair* them?
    Ditto home thermostats. Ever repair the controller
    in your furnace? Washing machine? Microwave oven?
    Garage door opener (and that's likely still thruhole!)

    (I've chosen each of these as I imagine each is on
    the order of a $100 item -- even if part of a more
    costly "system")

    Sure *someone* can repair them -- *if* the parts
    and documents are made available (and their time
    had no value).

    We've looked, carefully, at the choice of FRUs to
    support; how much does an assembly have to be worth
    to make stocking spares (AND a repair/test procedure)
    make sense ECONOMICALLY?

    Look at HP's consumer inkjets... three components:
    - a power supply (solvent welded shut)
    - electronics on a single board hanging off the back ("bag")
    - all the rest

    You *know* the depot just pulls the boards off the
    printers, runs them through a test cycle and restocks
    any that test good. The mechanisms ("all the rest")
    likely get tossed in the "plastics to be recycled" bin.

    What percentage of boards fail test? Are they repaired?
    Or, just discarded as "warranty costs"?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Lasse Langwadt@21:1/5 to Don Y on Wed Feb 28 18:02:31 2024
    On 2/27/24 23:04, Don Y wrote:


    I can't imagine any sort of volume production using,
    e.g.,  M1.6s -- or smaller!

    well, have a look at almost any laptop etc.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Don Y@21:1/5 to Lasse Langwadt on Wed Feb 28 14:02:32 2024
    On 2/28/2024 10:02 AM, Lasse Langwadt wrote:
    On 2/27/24 23:04, Don Y wrote:


    I can't imagine any sort of volume production using,
    e.g.,  M1.6s -- or smaller!

    well, have a look at almost any laptop etc.

    Those are *intended* to be serviced and, as such, have to walk a fine
    line between size and (re)assembly cost.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)