[carpe] 2017-07-18 CARPE Conscribillati: Soldering Party

[jep200404 at columbus.rr.com]

Thanks again to Pillar and Erin Moore for their generous hospitality.
As usual, there was plenty of salad, cookies, pizza, and beverages for all.

Tonight's soldering party was well attended.
Soldering is something that one learns by doing.
Many folks got experience unsoldering and soldering.
We went way past the normal quitting time to do more.

We learned by doing and making mistakes.

In part, the soldering party was to help Gabriel Sheeley solder things for his
presentation next week.

"Demystifying a Mystery Machine!" with Gabriel Sheeley
Tuesday 2017-07-25 17:30-19:30
http://info.pillartechnology.com/ovr_pi_mystery
There is limited space, so register early.

    gave both scrap Dell motherboards
    is working through nand to tetris

https://en.wikipedia.org/wiki/File:TG-7-B_teletype.jpg

Design and produce 3D printed, custom breast prosthetics
https://opensource.com/article/17/7/3D-print-breast-prosthetic

ESCO (on Indianola close to Morse) is extraordinarily expensive.
It is _the_ place to go if you absolutely have to have something right now.

Microcenter is much much less expensive than ESCO.

lead based solders versus lead-free solders

    lead based solders:

        bad:

            poisonous

        good:

            no whiskers
                wp:Whisker (metallurgy)
                https://nepp.nasa.gov/WHISKER/photos/index.html
                https://nepp.nasa.gov/WHISKER/
                https://nepp.nasa.gov/whisker/reference/tech_papers/Brusse2003-Zinc-Whisker-Awareness.pdf
            no tin pest
                wp:Tin pest
            lower melting point
                causes less stress to parts and printed circuit boards
                easier to hot enough to melt
            softer, so less prone to cracking
            higher surface tension when melted
                tries to center parts on pads
                capillary action wants to go through vias

tips:

    Use more flux and less solder.

Many beginners fail to wait long enough for the joint to heat up.

much too hot for brief time causes less damage
than barely hot enough for a long time

"helping hands" were very handy
They are not expensive. Microcenter has some cheap ones.

    http://www.microcenter.com/product/428657/HELPING_HANDS
    http://www.microcenter.com/product/420139/HELPING_HANDS_2XMAG
    https://duckduckgo.com/html/?q=helping+hands+alligator+clips

    Jigs, clamps, and helping hands
    http://makezine.com/2009/03/08/make-online-toolbox-jigs-clamps-and/

    Soldering with Helping Hands Alligator Clips
    http://www.robotroom.com/Breadboard-Hints-And-Tips4.html

    Third Hand++: a Multi-use Helping Hand for Electronics and Other Delicate Work
    http://www.instructables.com/id/Third-Hand-A-multi-use-helping-hand-for-electro/

bare copper versus iron plated tips

    Solder dissolves bare copper, but not iron.

    The benefit of iron plated tips is that they last a long time.
    The tips for most fancy temperature controlled soldering irons
    are iron plated for that reason.

    The drawback of iron plated tips is that the iron plating reduces
    the sharpness of edges.

    For the sharpest edges and points, use bare copper tips.
    The solder dissolves from the broad areas quicker than from the edges,
    so the tip shape changes. When that happens, use a file to reshape the tip.

tip shape

    conical shape versus chisel shape

    Conical is more popular.

    I prefer chisel shape. I find that the flat faces held against a
    solder pad are better at conveying heat than convex shapes. I find chisel
    tips to be suitable for a wide range of size of parts, even for soldering
    teensy surface mount stuff, because the corners are sharp.
    I.e., chisel tips scale well.

A wire of one of the 9 Volt battery clips, was very hard to solder,
even though it looked clean and there was plenty of flux.
Solder would just not stick to it.
In retrospect, I wonder if the strands were coated with a varnish.
I would try again, scraping with the edge of a knife

What is the make, model, and source of Ethan's temperature controlled iron
that people were using?

Ungar

    handle with three-prong power cord with:

        Ungar model #535-S 23 Watt heater and bare copper chisel tip

        Ungar model #4045-S 45 Watt heater and larger bare copper chisel tip

    file to reshape corroded tips.

    Princess 10 Watt heater with bare copper chisel tip (did not use tonight)

Heat gun from Harbor

    1500 W
    dual temperature
    $8 to $16 (depending on sales)

rosin flux is good for electronics

The paste flux for plumbing soldering is bad for electronics.

Ben screwed up guessing the polarity
We use "conventional electric current".
wp:Electric current#Conventions

wp: prefix means Wikipedia
To get good answers, consider following the advice in the links below.
http://catb.org/~esr/faqs/smart-questions.html
http://web.archive.org/web/20090627155454/www.greenend.org.uk/rjk/2000/06/14/quoting.html

Harvesting Electronic Components
http://www.instructables.com/id/Harvesting-Electronic-Components/

wait until July 4th
Serendipitous Garden Watering Nozzle From Water Balloon Filler
http://www.instructables.com/id/Serendipitous-Garden-Watering-Nozzle-From-Water-Ba/

Spicy Mushroom Curry
http://www.instructables.com/id/Spicy-Mushroom-Curry/