I bought a digital sundial online and deployed it in (what else?) direct sunlight in DC in June. Within 30 minutes the gnomon started to sag and the mount started to pull away from the gnomon at the bolt.
This shouldn't happen, right? Or is this expected?
Are you sure that this is ABS? (Since it is already trash, you can make a fire test. It should [correct me if i'm wrong] produce black smoke) Some ABS can becomes soft at already 80°C.
Just for fun I measured the temp of my gray sofa that was directly in sun light: It was over 70°C. So it could be possible that the sun light already was enough to weak the black ABS. Also the ground is interesting. Some idi**** room mate puts my black ¿abs? alarm clock on a metal windowsill because he want to know the temps there in the direct sunlight... the alarm clock becomes deformed :(
Probably white and/or coated ABS would be better. Also a inner rod would help against deformation.