P. J. Alling wrote on Wed, 23 May 2012 09:20:38 -0700 > Lenses are a long term investment, at least they used to be, plastic on a > bearing surface implies the opposite. No matter what plasticizers are lost > over time and the material becomes brittle and subject to cracking. > Eventually something important will break. Heat will exacerbate this process. > If the lens was cheap enough to be disposablethat would be fine but it's not > really.
It ain't neccesarily so! I'm confident that the Pentax plastic lens mount is made of a modern engineering plastic; these are heat-resistant, often self-lubricating, and do not contain volatile/migratory plasticizers. Unless subjected to severe mechanical stress it's likely that they will outlive the user… Regards, Jim -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
