Plastic part surface finish: please stop making mirror products

They are simply dust, fingerprint and scratch magnet, everything is summarised in the amazing book The Hardware Hacker: Adventures in Making and Breaking Hardware from Andrew ‘bunnie’ Huang

“My world is full of small frustrations like this. For example, most customers perceive plastics with a mirror finish to be of a higher quality than those with a satin finish. There is no functional difference between the two plastics’ structural performance, but making something with a mirror finish takes a lot more effort. The injection-molding tools must be pains-takingly and meticulously polished, and at every step in the factory, workers must wear white gloves. Mountains of plastic are scrapped for hairline defects, and extra films of plastic are placed over mirror surfaces to protect them during shipping. For all that effort, for all that waste, what’s the first thing users do? They put their dirty fingerprints all over the mirror finish. Within a minute of a product coming out of the box, all that effort is undone. Or worse yet, the user leaves the protective film on, resulting in a net worse cosmetic effect than a satin finish. Contrast this to satin-finished plastic. Satin finishes don’t require protective films, are easier for workers and users to handle, last longer, and have much better yields. In the user’s hands, they hide small scratches, fingerprints, and bits of dust. Arguably, the satin finish offers a better long-term customer experience than the mirror finish. But that mirror finish sure does look pretty in photographs and showroom displays!”

Linux/Ubuntu: Speaking clock with online TTS

As a followup of my previous article:

Ubuntu: talking clock every hours

4 years after the previous article, I still need this tool, but I wanted a more “natural” TTS.

So I’m using Voxygen, a natural TTS provider (very good for French), retrieving the generated voice with wget and the following command:

wget --quiet --no-check-certificate -O /tmp/clock_`date +\%-1H`.mp3 "https://www.voxygen.fr/sites/all/modules/voxygen_voices/assets/proxy/index.php?method=redirect&text=il est exactement `date +\%-1H` heures.&voice=Loic"

Here is the script to run every hours:

if [ ! -e /tmp/clock_`date +\%-1H`.mp3 ]; then wget --quiet --no-check-certificate -O /tmp/clock_`date +\%-1H`.mp3 "https://www.voxygen.fr/sites/all/modules/voxygen_voices/assets/proxy/index.php?method=redirect&text=il est exactement `date +\%-1H` heures.&voice=Loic"; fi ; mpg321 /tmp/clock_`date +\%-1H`.mp3 --gain 200

We will be using gnome schedule taks:

screenshot-from-2017-01-05-100935

Portable soldering fumes extractor fan DIY (battery operated and USB rechargeable)

Here is a very simple fume extractor fan, to put an halt to apnea soldering.

Made of:

  • DC/DC buck boost converter (3€ on ebay)
  • USB battery pack 5€
  • scrapped fan
  • scrapped switch
  • scrapped potentiometer
  • Hammond prototype case (1€, same as my USB motion sensor)
  • nice labels
  • double side tape

Enough talk, a picture:

And in action, can suck up to 15cm at medium speed:

This “hack” took me 30min, and costs close to nothing, while some have been down to build a DC/DC converter for this!

Thing to add in the future:

  • active carbon filter for better filtering, but usable as is for small jobs: you don’t get fumes in your face anymore.
  • USB light for soldering in the dark

My favourite use: in the freezer/fridge, when you forgot to chill beers for an unexpeted party, it takes only 10min to have freezing beer instead of 1h. (remove the carbon filter first…)

Mes trouvailles du jour : 6 July 2016

  • A Parent’s Guide Chapter 5: Teaching Adolescents: from Twelve to Eighteen Years
    Ce qui est merveilleux avec le cerveau humain, c’est qu’on peut arriver à des conclusions diamétralement opposées sans aucune difficulté…

    "Teach your children that the prophets have condemned it as a sin throughout the ages and that they can choose not to do it."

    "The sin of masturbation occurs when a person stimulates his or her own sex organs for the purpose of sexual arousal. It is a perversion of the body’s passions. When we pervert these passions and intentionally use them for selfish, immoral purposes, we become carnal."

    "Your teenagers will also be tempted to have sexual relations with others before they are married."
    (Permalink)