Glue 101: It’s A Sticky Situation (How Tacky)
So, your old wooden dining room chair finally came apart after being loose and wiggly when anyone sat on it (for the last two years!). Hopefully no one hit the floor when it broke. You go to the big box home center to buy some glue to repair the chair and are confronted by six shelves full of so many different types of adhesives that your head starts to spin. All you want to do is put your chair back together, but what product would be the best for that task?
Let’s start with a little history. The first glues were made from birch tar and plant gum and resins. Then people started using egg whites, animal parts, and fish bladders. World War I introduced casein glues made of milk and nitrocellulose glues. Then in the 1930s the plastic and chemical industries developed materials called adhesives and plastic or synthetic resin glues. World War II led to further developments for the military: neoprenes, epoxies and acrylonitriles (also duct tape, but that’s for another column). They became available commercially in the late 1940s and early 50s.
Today we use predominantly synthetic adhesives, which can be categorized as reactive and non-reactive. Reactive adhesives include the epoxies, urethanes, and cyanoacrylates. These adhesives harden through a chemical reaction, either with two parts being mixed together, or exposure to heat, air, or moisture. Non-reactive adhesives generally harden as a solvent evaporates. Examples are white glue, contact adhesive, and rubber cement.
We all remember the Elmer’s White Glue from early school days. (No, I didn’t eat it, but I know some kids who did.) White glue and yellow glue are called polyvinyl acetate glues (PVAs). Both of these glues will form bonds stronger that the wood surrounding them. The white glues don’t sand very well, tend to run and have a low initial tack. That is why the yellow glues were developed. They have a higher solids content (thicker and they sand better) and have tackifiers added so they set up more quickly. Though the yellows are easier to use, there really isn’t any difference in strength from the whites.
By now, most of us have heard of Gorilla Glue. This is an example of polyurethane glue. This type of glue requires some moisture to be present to cure and can be used with wet wood, forming a strong waterproof bond so it is often used for exterior woodwork. It is pretty difficult to clean up, and if you get it on your skin you’ll be wearing it until is wears off. Be cautious and wear gloves.
Epoxy glues come with two parts, a resin and a hardener. They can be a little pricey but they form a heat-resistant, waterproof, very strong bond that requires only light clamping. Epoxy is very versatile and can bond a wide range of materials from wood to glass to leather.
Another product that can bond a wide range of materials is cyanoacrylate glue (super glue). This one is also a bit pricey and is not real resistant to shock (fragile bond). It is very handy for quick repairs but doesn’t fill gaps, so the bonded surfaces need to be held tightly in place until the glue cures (usually in about a minute, or so).
Contact cement can be used to bond wood, plaster, plastics, metal, drywall, cork flooring and more. Both surfaces are coated with cement and allowed to dry. When pressed together they bond immediately so be sure you are ready. They won’t require tight clamping and the bond is water/heat-resistant. There is water-based contact cement for products and situations that won’t allow the typical flammable (and smelly) solvent-based version.
Construction adhesives are the thick glues that come in tubes like caulk. One version is Liquid Nails. There are many varieties of this type of adhesive, each designed for specific uses and materials. You will want to read carefully which tube to buy. For example, tub surrounds and foam board require specific types of adhesives that won’t chemically interact with and melt them.
So, getting back to our chair repair, as you can see, there are a variety of glues that would work just fine. Since this is a dining room table chair and won’t be exposed to weather or moisture, the yellow glue would be the most economical type to use. If, however, you have other repairs around the house, you might want to consider one of the types that would bond a wider variety of materials. There are certainly many more types of adhesives and products we could discuss but this week’s topic is Glue 101. You’ll have to “stick” around for Glue 102 to learn more (oh, that was so bad). Here is a helpful link that will help you in choosing which adhesive will work best for your given situation: www.thistothat.com.
With over 20 years experience in Home Maintenance and Repair, Remodeling and Building Inspection, Kheli started the Handy Woman LLC to be ‘not just your average contracting company’, but to also teach people how to take care of their homes by offering do-it-yourself coaching and how-to classes. Along with typical home repair and maintenance services, her focus is to help our elders age-in-place and teach women homeowners how to understand and care for their homes.
For more information please call Kheli @ (303) 999-5812, or visit www.thehandywomanllc.com.