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.

Author: Ed

  • It’s a Small World

    This quarterly tabulation doesn’t include the hundred-odd of you who click in through the RSS feed from wherever you may beq, but it’s in the right ballpark:

    Country Views
    United States 37459
    United Kingdom 4366
    Canada 4243
    Germany 2501
    Australia 2342
    Netherlands 1759
    Finland 1723
    India 1584
    France 1491
    Spain 1343
    Italy 1304
    Brazil 1157
    Poland 959
    Belgium 815
    Russian Federation 748
    Argentina 717
    Indonesia 627
    Portugal 614
    Turkey 591
    Sweden 582
    Thailand 559
    Romania 538
    Republic of Korea 528
    Malaysia 521
    Mexico 510
    Czech Republic 505
    New Zealand 496
    Philippines 476
    Hungary 468
    Japan 458
    Denmark 452
    Singapore 443
    Switzerland 427
    Greece 415
    Viet Nam 401
    Taiwan 385
    Ukraine 345
    Ireland 314
    Israel 304
    Norway 304
    Bulgaria 300
    Austria 295
    South Africa 276
    Lithuania 245
    Croatia 240
    Slovakia 238
    Slovenia 232
    Hong Kong 225
    Pakistan 203
    Serbia 198
    Colombia 176
    Latvia 160
    Egypt 159
    Estonia 136
    Chile 129
    Moldova 114
    United Arab Emirates 108
    Saudi Arabia 103
    Peru 86
    Tunisia 67
    Venezuela 60
    Sri Lanka 60
    Iceland 59
    Bosnia and Herzegovina 55
    Costa Rica 54
    Belarus 53
    Malta 53
    Ecuador 51
    Macedonia 49
    Cyprus 46
    Morocco 46
    Syrian Arab Republic 38
    Bangladesh 37
    Algeria 35
    Panama 34
    Puerto Rico 34
    Lebanon 32
    Trinidad and Tobago 31
    Iraq 29
    Jamaica 28
    Kuwait 28
    Uruguay 26
    Armenia 26
    Kenya 26
    Bermuda 26
    El Salvador 24
    Jordan 23
    Georgia 23
    Qatar 22
    Luxembourg 21
    Guatemala 21
    Cambodia 21
    Brunei Darussalam 20
    Mongolia 18
    Albania 18
    Dominican Republic 17
    China 17
    Bahrain 16
    Mauritius 15
    Nepal 15
    Monaco 14
    Oman 13
    Ghana 13
    Bolivia 13
    Sudan 11
    Honduras 10
    Nigeria 10
    Guam 10
    Libyan Arab Jamahiriya 9
    Paraguay 9
    Namibia 7
    San Marino 7
    Montenegro 7
    Maldives 7
    Macao 7
    Yemen 7
    Malawi 6
    Barbados 6
    Ethiopia 5
    Vanuatu 5
    Fiji 5
    Togo 4
    Netherlands Antilles 4
    Bahamas 4
    Cameroon 4
    Mauritania 4
    Nicaragua 4
    Botswana 4
    Norfolk Island 3
    Myanmar 3
    Uganda 3
    Andorra 3
    Belize 3
    Côte d’Ivoire 2
    Lao People’s Democratic Republic 2
    Mozambique 2
    Cape Verde 2
    French Guiana 2
    Swaziland 2
    Liechtenstein 2
    Azerbaijan 2
    Jersey 2
    Cuba 2
    Haiti 1
    Liberia 1
    Guyana 1
    Niger 1
    New Caledonia 1
    Zimbabwe 1
    British Virgin Islands 1
    Guadeloupe 1
    Northern Mariana Islands 1
    United Republic of Tanzania 1
    Senegal 1
    Antigua and Barbuda 1
    Madagascar 1
    Cayman Islands 1
    Kyrgyzstan 1
    Afghanistan 1
    Saint Lucia 1
    Papua New Guinea 1

    Mad props to whoever clicked in from Afghanistan: I hope you found whatever you were looking for!

  • AMP 842448-2 HF PCB Filters: Still Alive

    A vial in the bottom of Mad Phil’s EMI Go-Kit contained a handful of these doodads:

    AMP 842448-2 HF PCB Filters
    AMP 842448-2 HF PCB Filters

    The label on the vial came from AMP with a handwritten 842448-2. Searching on the obvious terms eventually produced a Surface Mount EMI Filters catalog from Spectrum Control, with page 25 saying that it’s a 10 A DC ferrite pi filter with a 20 dB insertion loss over 100 MHz; evidently, SC bought AMP’s product line and is keeping it alive for all the Mil-Spec folks. Oddly, you can’t find that catalog using the site’s built-in search function with the part number.

    Rather than keep an entire catalog of parts I’ll never have, I used pdftk to snip out and rename the page for later reference:

    pdftk surfacemountcatalog.pdf cat 25 output "AMP 842448-2 HF PCB Filter.pdf"

    After it reaches the Internet, it never goes away…

  • Jacking Up The Microscope

    Microscope with machinists jack
    Microscope with machinists jack

    The stereo zoom microscope over the electronics bench lives on the end of long support arm that tends to be just slightly wobbly. Part of the problem is that the far end is anchored on the sponge-backed laminate flooring I put atop the bench, but it’d be slightly wobbly even with a firm base on the plywood bench top.

    So I prop up the microscope with a machinist’s jack and it’s all stable & good.

    This one happens to be from an ancient Starret 190 set that I accumulated along with some other tooling, but any of the cheap imitations would work just as well.

    The two bubble level vials help get the microscope axis exactly perpendicular to the bench surface, which makes the difference between good overall focus and a blurred image with a single line in focus. Here the jack is vertical and the microscope is tilted slightly toward the edge of the bench; the jack has a pivot below its knurled top plate.

  • Garden Dragonfly Ornament: Eye Re-Repair

    Alas, urethane glue didn’t hold the eye marbles in the garden dragonfly ornament for very long. Although the cured glue had a wonderfully smooth surface where it contacted the balls and it had plenty of contact area, that wasn’t enough.

    This time, I used acrylic caulk that should stay gummy enough to maintain a good grip:

    Garden Dragonfly ornament - re-reglued eye marbles
    Garden Dragonfly ornament – re-reglued eye marbles

    The next step, I suppose, will be to drill a hole in each ball for a stud and epoxy the things in place…

  • Monthly Subconscious: Dysfunctional Father

    This may be a universal truth, as seen from both sides of the divide:

    Dysfunctional Father
    Dysfunctional Father

    In text:

    dysfunctional father worry love
    protect awkward girl child

  • Fundamental 3D Printing Patents

    DIY 3D printing seems surrounded by Good Ideas that don’t happen, which led me to look up some of the early patents in the field. As nearly as I can tell, any bright idea one might have has already been patented; although you can usually get away with tinkering it up in your basement (because you’re not worth enough to interest the patent holder’s attorneys), anything beyond that will darken your skies with lawsuits.

    The granddaddy of all 3D extrusion machines seems to be US5121329 (Crump → Stratasys 1992-06-09): Apparatus and method for creating three-dimensional objects

    Exploring the patents referencing that one as a foundation should keep you busy for a while; the PDF has clicky links.

    Some fine tuning on the theme:

    US6085957 (Zinniel/Batchelder → Stratasys): Volumetric feed control for flexible filament

    US5303141 (Batchelder/et al → IBM): Model generation system having closed-loop extrusion nozzle positioning

    Congealing 3D objects in a vat of goo probably starts with 4575330 (Hull → MVP 1986-03-11): Apparatus for production of three-dimensional objects by stereolithography

    Remember: I’m not a patent attorney and my opinion is worthless…

    US5121329 - Figure 1
    US5121329 – Figure 1

  • A Fork In the Path

    The original path curved away from the new Nutt MECS Center at Trinity, but even engineering bears won’t follow a path that leads in the wrong direction:

    Fork in the path at Trinity
    Fork in the path at Trinity

    An old story has it that [name of administrator] at [name of new college] had the architect remove all but the most obvious walking paths from the new campus plans. After the first year passed, then they paved the routes that people actually used.

    Vassar College has a good example of that design in the residential quad:

    Vassar Paths - Paved Quad
    Vassar Paths – Paved Quad

    But even they won’t slash diagonals across a lawn just for students:

    Vassar Paths - Grass
    Vassar Paths – Grass