• Silver Glue Doesn't Work

    Jarrett10/02/2018 at 17:26 0 comments

    As of last log, I was trying to use some silver glue to attach all the LEDs to some copper wire. After drying though, it immediately crumbled in my hands and was pretty much useless. Maybe I'm doing something wrong, but I'm probably going to abandon that method.

    Inspired by Mohit Bhoite:


    I picked up some 20 mil brass rod.

    And I bent it into shape and super glued it to my wood jig. Superglue just kinda absorbs into the wood, though, so I also laser cut one of the templates in acrylic. Acrylic doesn't seem to work as well at small scales like this, it gets all melty, but we'll see how it goes.

  • A test jig

    Jarrett08/16/2018 at 18:11 0 comments

    As mentioned earlier, the plan was to laser etch a stencil, and use it for assembly.

    0603 components are hard to work with, without a PCB!

    I laser-etched a piece of plywood, juuust deep enough to nestle some LEDs and a piece of wire. Then, I used conductive silver glue (in the syringe) to glue them to the wire.

    The idea there is (from experience) it's pretty difficult to simultaneously hold down the LEDs in the proper position, and deadbug solder them. The hope was that the glue would just be able to get blobbed in appropriately, without disturbing the components. And, honestly, it didn't really work.

    The LEDs love to jump around, and part of the issue is that my tweezers were ferrous. So just the slightest bit magnetic, and that messed with stuff.

    So this while this glue is drying, I'll try again, maybe try solder again, maybe try with glue and holding this down better somehow.

    Side note:

    When you order a bunch of conductive glue from China, and then forget about it while it takes the 2-month boat trip across the ocean, it is a total mindfuck when you randomly get a bunch of syringes in the mail.

  • The Original Plan

    Jarrett08/07/2018 at 20:54 0 comments

    If I charlieplex an LED cube, using 0603 LEDs, it could look like this:

    Pictures pulled out from my archive, where I've been toying around with this idea since the last Square Inch Contest, three years ago.

    That's pretty dense, but the majority of it can be made layer-by-layer, like this:

    That means each layer looks like this:

    A couple years ago, I laser cut a stencil and soldered up one layer, and it seemed to work okay. Not easy, but it was possible.

    I never did multiple layers, and the hard part would be getting those vertical wires attached, near the centre of the cube. I have an idea, though.