Tuesday, August 25, 2015

Quickie #2: protecting Fenix LD12 side switch

The Fenix LD12 is quite powerful (125Lm) and small size (powered a single AA cell); the flashlight is quite tough with it aluminum body but it has two weaknesses : the rubber capped buttons.

To keep the flashlight waterproof, these rubber capped buttons needs not to be altered. I already needed to change the back On/Off button due to untimely leak but its construction doesn't allow to protect it; though we can protect the side button (replaced by a steel capped button on cutting edge Fenix flashlights!)
Which material could be used for that purpose?
A few possibilities were allowed to protect the side buttons. We needed the material to respect some characteristics :
  • Being firmly wrapped around the LD12 body
  • Strong enough not to get worn to quickly
  • Springy enough to allow the button under it to be pressed

What about using heat shrink tubing usually aimed toward electrical isolation?
When heated these tubes shrinks and wrap firmly around the underneath material (whatever it is...).
It is available in a large range of diameters : at home it had it in 1,3, 4.5 and 6mm... but it exist in 12.5, 25 and even 35 or 75mm...
Once shrunk, it resists quite well to tearing, scratching and break through (i used a dentist toothpick):

It looks like the perfect candidate for the job!

Let's wrap!

  1. Cut the tube at the right length, with heat it will shrink (in diameter) but length won't be altered
  2. hold the tube carefully: mainly if it was stored flattened.
  3. heat gently a little area with a soldering iron until you get one shrunk ring (3-6mm wide), starting from the collar
    (NB: try to heat homogeneously or you'll get thicker areas where the tube gets heated too long)
  4. repeat, moving little by little until all the tube has shrunk firmly around the body and press with your fingers after each step -before it cools down-(take care not to overheat the side button!! if your fingers are burnt while pressing... it was too hot!)
  5. finish with the Flashlight head
  6. re-heat area that aren't shrunk enough
  7. Press button area after heating a second time to get the button layout appearing (heating too much will make the tube thicker and you won't see the layout after pressing)

The Flashlight is now more wear/break-through/scratch proof (the side button at least). The result is far from perfect, but that was a first try!

Saturday, August 22, 2015

Quick review: 32GB PNY Micro Metal Attaché USB Flash drive

Today, i was thinking to get a new small USB flash drive to keep in my pocket, my choice went for the PNY 32GB USB-2.0 Micro Metal Attaché: P-FDI32G/APPMT2-GE
Why choosing a 2.0 flash drive?
... When 3.0/3.1gen1 are available and 3.1gen2 will come soon...
  • Price : 19€ for 32GB
  • My laptop is from 2011, it doesn't feature any 3.0 host...
  • I already have an EMTEC 16GB USB 3.0 flashdrive when i need high speed on compatible computers
  • Will USB type-C flash drives come soon??
Form factor and characteristics
  • Size: 18 x 12 x 7mm, 5g, this is quite small and light, perfect for my needs here; it is quite smaller than my little 16GB EMTEC of the above picture
  • Reliability :
    • 2 years warranty, Data retention: 10 years.
    • Write/erase cycles: 10,000 minimum.
    • It doesn't look rock solid (the metal part is really thin), really looks cheaper than the LaCie 16GB Key.
    But something interesting is written on the back of the box:
  • Speed (theoretical):
    • Write Speed: up to 8MB/s
    • Read Speed: up to 25MB/s
  • Speed (real-life): With 10MB files (the benchmark default value), we get 18.2MB for Read speed, and 4.5MB/s for Write speed, far below the theoretical values... !

    With 100MB files, we get some better results R:21.9MB/s, W:9.7MB/s:

    With 1GB files (only 10 tests, not to spend the whole day waiting...)R:22.4MB/s, W:11.4MB/s:

    Let's see how it behaves with small files :
    With 1MB files R:17.8MB/s, W:566.3kB/s:

    With 4MB files (approximate size of a song or a 12MPx picture):

    So, we can see that small size file are pushing the flash drive to its limits, resulting in very low speed (566kB/s!!!); Storing larger files shows better results (as good as the theoretical speed announced by the brand)
Pros ... and Cons
  • + Nice size and weight
  • + doesn't protude much from the computer USB host
  • + Average speed is OK for medium and large files
  • - Extremely low speed for small files, cannot be really used as a liveUSB medium (my USB3.0 EMTEC 16GB gets R:35MB/s W:10MB/s with 10MB files on a 2.0 host!)
  • - Not very tough construction, might not survive for years?