Kapton, kapton solves everything... almost.



[ Thursday - January 17, 2019 ]
As it turns out, the week of January 14 through January 18 has LA seeing rain the entire week.  This is unusual, but a welcome and fun change.  On Thursday, January 17, the rain was monsoonal with the exception it's cold instead of warm.  In the past, I would ride around with the face shield cracked open to prevent from fogging up.  When I got the Drudi XD4, I bought a pinlock face shield with an anti fog lens.


Drudi helmet on the left.

I still ware the Moxx helmet for commuting.  Since I didn't want to spend the extra $'s for a pinlock and fog lens, I went ahead and bought just the fog lens.  Now before you go on and ask the question, "Is there something really special to the anti-fog lens?"  The answer is, yes.  There is a special coating on the lens that prevents moisture from condensing on the lens.  To a point.  It's not just the air gap between the face shield and the anti-fog lens.  But... there is always a "but".  But the air gap between the anti-fog lens and the face shield has to be completely sealed off otherwise moisture can get in between the two lenses and fog up.  If you ever look at ski goggles, they have two lens with an anti-fog chemical coating.

Since I went cheaped out on not getting the pinlock face shield, I had to get the second fog lens on the face shield some how.  I originally used scotch tape (for taping paper together) to hold the anti-fog lens on the face shield.  It worked well enough until it started raining really hard.  At that point, water got in between and pooled in the gap between the face shield  and the anti-fog lens.  The Scotch tape glue didn't stand a chance against water.  Since it worked well enough, it's time to find a better tape to hold the anti-fog lense to the face shield.

Hah!  It's magic.  Kind of.  What's the answer?  Why, Kapton tape.  Also known as polyimide film tape.  We use it a lot at JPL.  It's great as an insulator.  Not only that, it sticks to smooth surface and to itself like no tomorrow.  The glue on the film doesn't peal off when the tape is removed.


The gold tape on the face shield.


Here's a closer look.

Well, kapton tape doesn't solve everything, but it definitely solved my anti-fog on a non-pinlock face shield.  Sure enough, water never got in between the face shield and lens.


Written on: January 22, 2019
Last modified: January 22, 2019