I've been googling ways to joint the rubber with chemicals but that seems an unlikely method. I'll probably use black silicone or some other black stuff to seal the miters. Any advice is always welcome.
Jerry in Denver
I don't think Silicone is your best choice.... I suggest you do your own testing before you choose but I can tell you back in the 70's a buddy had a radiator hose fail while traveling from Las Vegas to San Diego... & while he had access to water to fill the radiator the only thing he had to attempt to repair the hose with was Super Glue.... He tried it & it worked so well it didn't leak a drop... He wound up picking up a replacement hose but left that hose in place for nearly six months just kinda as a test to see how well it would hold up...