Whether faced with repairing broken glass or trying to construct a container from glass panels, gluing glass to glass is not typically an easy task. Glass is generally non-porous, meaning it has a very smooth surface. Even glues that appear to adhere to glass may, after a short period, peel away and cause the glued item to fall apart. A few tips to keep this from happening include cleaning the pieces thoroughly, choosing the correct glue, and supporting the piece properly as it dries.
Cleaning the glass pieces is typically one of the most important steps in gluing glass together. This may be slightly dangerous or difficult if one is gluing together broken pieces, but it isn’t impossible. With broken glass, one should wear close-fitting leather gloves. Leather is generally tougher than rubber and well-fitted gloves should provide enough dexterity to handle the pieces easily. Those working with large, unbroken panels may still want to wear gloves to protect their hands from glue or minor cuts from unfinished corners.
Proper cleaning before gluing glass together usually involves wiping the pieces down with glass cleaner and a soft cloth, or with alcohol wipes. This is especially important for the areas to be glued. Oil, dust, and dirt clinging to the glass may prevent the glue from sticking to the glass itself and create a weak joint. Fortunately, a gentle swipe with a cleansing cloth usually remedies this problem.
The second tip to gluing glass involves choosing the correct glue. White school glue and hot glue are poor choices because they are generally designed to hold porous objects together. Aquarium cement, E6000 adhesive, and thin, clear industrial glues are generally the types of adhesives one should look through. Broken glass often looks better when repaired with E6000 or clear adhesives. Large projects that must be watertight, like glass planters or homemade aquariums, usually hold together well with aquarium cement.
Most glues require a curing time, and this is especially true when gluing glass. One should generally focus on gluing glass together just a few pieces at a time, allowing these smaller pieces to cure and then joining together the resulting larger pieces. Painters tape and supports in the form of sand or small blocks of wood can reinforce the glued joints and help the pieces keep their shape. The glued joints of large containers may also benefit from painters tape and corner clamps padded with soft cloths. Cloths under the flat parts of the clamps protect the glass from scratches.