To some contemporary consumers, the vintage Velcro used in the authentically made NASA Velcro watchbands confounds expectations. While it is understood that the SEB12100030 specification is a historical document, it is not always appreciated how much we take for granted modern materials and construction methods in making a quality strap. Quality, that is, if the criteria is "hard wearing", but not if the desire is being as authentic as possible.
This contradiction is similar to the decision OMEGA made to preserve the Hesalite crystal in the Omega Speedmaster despite the availability of better alternatives. Nevertheless, I sell these straps as suitable for everyday use, provided allowances are made for performance of original materials, so it is important I allay these concerns.
One of the chief drawbacks of vintage Velcro (circa late 1970s) is that its is simply not as hard wearing as we have come to expect. For that reason, I provide an alternative watchband using the latest mil-spec Velcro loop tape, which is an exceptionally hard-wearing and superb watchband material, outperforming loop tape in terms of fray resistance and open/closure cycles used in supposedly "quality" watchbands.
Sometimes one hears concern of the vintage Velcro loop tape that despite using the gentler #65 type hooks (compared to the specified #80 alternative), initial use will cause some of the pile on the loop tape to pull away. The remedy is simple: these loose fibres can be tidied up by sparsely snipping with sharp scissors and quickly the remaining pile that is left will stabilise and continue to provide adequate peel strength.
I advise wearing the short watchband by cinching the strap to one springbar first, and then using the second springbar to secure on the strap on wrist as shown in the image below. This way, the second spring bar acts tighter on the Velcro tape than if the steel loop was threaded directly, and therefore prevents the strap fully opening if the hook and loop closure were ever to accidentally peel apart. Also, the springbars are just as secure as if in the traditional two-piece strap and buckle arrangement.
You can reassuringly feel how secure this arrangement is every time you take off the watch.
Another issue sometimes remarked upon is a small gap between the loop tape and the watch lugs. Is this strap really tailored for a watch with 20 mm between the lugs?
Here we have to consult the blueprint SEB12100030 in detail. The watchband is fabricated as laid out there, which says to cut the loop tape to 47/64 inches (in other words, 1/64 of an inch less than 3/4 inches, about 18.5 mm). What an extraordinary number you may think, until realised that a reasonable tolerance for cutting must have been ± 1/16 inch from the cut line. This means a 1/8 inch difference between narrowest and widest, and the widest is 51/64 inch, or 20.2 mm.
So to be within tolerance, a vintage Velcro loop tape could be a whole 3 mm thinner than the width of the 20 mm lugs and still be within the minimum width allowed. But that wouldn't do nowadays, so I commit to exceeding the specification, and cut to 1/32 inch (1 mm) within the allowed maximum. Nevertheless, the very nature of the overall design means there will always be a tiny gap - unless, of course, you are wearing a 1960's Omega Speedmaster case with straight lugs (19 mm width).
The NASA watchbands should be washed regularly, and it is sufficient to use running water with hand-soap and then dry with paper towels.
They are 100% Nylon. How can you tell if the hook and loop tape is Nylon or Polyester? Most easily when compared side by side. Black polyester will always have a navy blue hue, almost black, but not quite compared to the true black of dyed Nylon.
Finally, please note that the printing on the Olive Drab tape is made with a simple typewriter, or stamped with permanent ink. The markings will withstand many washes, but it is just a pigment ink and will abrade off eventually.