We get a lot of questions from customers and other artisans, seeking advice on adhesives for use on glass projects made for use outdoors. (One of our top suppliers, Dymax Corp., gets questions about that, too — and they often send those calls our way.) In the course of addressing all those inquiries, we’ve gained a lot of hands-on experience with assembly and repair of garden art, light shades and fixtures, and other outdoor decorations. This is the season for outdoor projects, and the popularity of the topic inspired this post.
As with any glass assembly (or repair) project requiring adhesives, the most important consideration is the nature of the materials you want to stick together. The chief goal is to choose an adhesive that forms a strong, long-lasting bond between those materials. In an outdoor application, of course, it’s also important to find adhesives that are water-resistant.
Today we’ll look at two scenarios. Both involve bonding pieces of transparent glass to other materials, and both use adhesives that can be cured rapidly using long-wavelength (365 nanometer) UV light sources. (Moderately priced UV lights are available from CLK and other vendors; most grow-light style bulbs will work, as well.)
If you’re gluing transparent glass to transparent glass, Both Dymax Light Weld® 425 and Dymax Light Weld® 429 will provide very good results. By allowing you to shine the UV light through the glass to cure the glue “inside” the joint, these adhesives can form bonds stronger than the glass pieces themselves. Light Weld® 429 forms clear, see-through bonds, and is virtually invisible when applied carefully. Light Weld® 425 forms a somewhat stronger bond, and cures to an inconspicuous “water white” color.
If you’re attaching transparent glass to metal Dymax Light Weld® 429 is your best all-around choice for outdoor applications. It forms durable, water resistant bonds when cured using 365 nanometer UV light. One notable exception: If your glass-metal bonds need to withstand the rigors of dishwashing — as in the case of pitchers, mugs, or other glassware — not just the natural elements, you should use Dymax Light Weld® 425.
If you’re working with opaque glass or other non-transparent materials, you’ll probably want to find an alternative to light-cured adhesives. That’ll be the topic for a future blog post. Stay tuned.