When It’s Not WoodJune 23rd, 2011 by DWM Magazine
Door and window manufacturers trust ASTM testing standards to ensure the quality of bonding wood components for interior and exterior parts.
But what standards should you follow when bonding substrates other than wood in the manufacture of doors and windows?
ASTM standards cover nonstructural lumber products centered around a variety of wood species only. At this moment, ASTM does not offer separate criteria for adhesives applied to such substrates as acetylated lumber, plastic composites, thermally treated lumber and bamboo. Yet, these substrates are finding their way into mainstream use within the door and window manufacturing industry.
Testing in our lab at Franklin Adhesives & Polymers indicates that these new substrates absorb water and behave differently than wood does. Therefore, we cannot assume that a particular adhesive performs the same on any of these substrates as on wood components. And this suggests the possibility that you might – just might – need to use a different adhesive when bonding alternative substrates to achieve the same degree of water resistance.
Absorption variations also lead us to believe that, rather than revising existing standards to include these newer substrates, ASTM might need to develop a separate set of standards for them.
We plan to spend more time in the lab researching adhesive performance on the newer substrates. In the meantime, we would like to hear your thoughts on working with these materials. What do these new substrates bring to the industry and your customers? Do the same adhesives you have been using to glue wood components seem to work as well on the alternative materials? Feel free to leave a comment or e-mail Michelle at firstname.lastname@example.org.