|VIUD Prototype #2|
Machining will again be done by myself with a few tricks learned from the first prototype. The process went well although I did have issues with the cap not lining up perfectly with the body when closed despite trying to be very careful when tapping the threads. I believe the issue here is merely due to the inherent inaccuracies of manual tapping.
Despite a slightly crooked cap pressure testing at 3000 psi for 1 hour passed the first time without any leakage. There is little point in destructive stress testing this prototype as we won't be using the same type of Aluminum in the final design, and it should be same strength as the Brass prototype anyways.
One notable observation is that this prototype is significantly lighter than the first one weighing in at only 60 g despite using a Brass thread plug. This is much nicer than the 150 g of the Brass prototype and while it is heavier than most consumer level USB drives you see it is light enough to not really notice it in your pocket, at least no where near enough to be annoying.
|Prototype #2 With the Cap Off|
I should note that while I am writing this blog entry in the summer of 2013 I actually made this prototype nearly a year ago in the fall of 2012. Since then this prototype has been in my pocket or backpack almost everywhere I go. After using it some hundreds of times I can't really find any fault in the design other than it not fitting some closely spaced USB connections with other things plugged into them. Its convenient, works well, nothing has broken or worn noticeably, it is relatively pretty despite my limited machining skills, and it has turned a few heads from co-workers and friends (always a good sign)!