From: blockedofcourse@foo.invalid   
      
   On 12/3/2025 5:05 AM, Glen Walpert wrote:   
      
   > You can get nearly water clear epoxy.  If you have ever been to a bar or   
   > restaurant with a thick clear coating on tables or bar, often with stuff   
   > embedded, that is epoxy.  You cannot however get any clear epoxy with   
   > decent UV resistance - clear epoxy coated tables used outdoors must be   
   > coated with a UV blocking polyurethane in order to survive, and they need   
   > to be recoated every 3 to 5 years.   
      
   But, are they recoated because the abrasion of daily use wears the   
   coating off?  Or, does the exposure to sunlight do that?   
      
   > There is no clear casting material   
   > available with 20 year life expectancy when exposed to direct sunlight,   
      
   As I mentioned to Martin, upthread, only some of my devices are exposed   
   to sunlight.  ALL (or, almost all) are exposed to the temperature extremes   
   I cited.   
      
   But, I would hate to have to stock a "UV tolerant" and "UV intolerant"   
   version of each module.  There would be no way I could ensure a third-party   
   installer would use the correct version in a particular application.  So,   
   easier to just have them all the same (which is what my "glass inserts"   
   approach does).   
      
   I can (electronically) inventory every device and have the UV/no-UV devices   
   report different part numbers.  But, have to rely on someone on-site (i.e.,   
   the installer) to accurately describe where each is sited.  And, hope their   
   descriptions include the information I would need to detect a "misapplication".   
      
   [If you look at the work of many tradesmen, it is often "barely competent".   
   And, if the consequences don't manifest for years, they'll be long gone.]   
      
   [[A reputable electric company (electrician) in town installed a pair   
   of coach lights on the neighbors back porch.  When I visited the neighbor,   
   I had to list the things that were wrong with the installation:   
   - ROMEX stapled to timbers (no EMT)   
   - lights located at eye level   
   - no boxes to support the fixtures, just notches snipped out of their   
      bases to allow the cable to enter/exit the fixture while the fixtures   
      were secured to the timbers with wood screws   
   - no GFCI on the circuit (outdoor, eye level)   
   The owner of the company paid a visit and was embarassed by the quality of   
   workmanship.  What would the outcome have been had I not commented on it?   
   Maybe when the house eventuall was resold and a home inspection flagged   
   the work??]]   
      
   > for that you need to use the method used by solar panel manufacturers -   
   > laminate to the back of a piece of tempered glass, which will provide a   
   > weather resistant UV blocking outer layer for the assembly.  Some   
   > flexibility of potting material is required to accommodate differential   
   > thermal expansion, silicone or polyurethane are more likely to work than   
   > epoxy.  Solar panel manufacturers did a lot of research to find the best   
   > compound, but I forget what it was, you could no doubt find out with a bit   
   > of searching.   
      
   Thanks!   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)