Using adhesives pt. 1

Using adhesives pt. 1

Join us as we learn about using adhesives for your projects!  These slides are part of a powerpoint presentation created by shop teacher Tom Bockman.  If you would like to view the entire presentation, take a look at our YouTube channel.  A copy of the entire Woodworking curriculum is available and will be listed for sale soon.  Email us if you are interested.

Adhesives chemically attach two or more surfaces together. The right adhesive can make any fix quicker and longer lasting.

Multipurpose Adhesives

If you keep a small assortment of multipurpose adhesives in stock you will be able to make a wide variety of repairs. Follow along as we learn the most common types of multipurpose adhesives!

White glue (polyvinyl acetate, or PVA): PVA glue is a white liquid, usually sold in plastic bottles. It is recommended for use on porous materials — wood, paper, cloth, porous pottery, and nonstructural wood-to-wood bonds. It is not water resistant. Clamping is required for 30 minutes to 1 hour to set the glue; curing time is 18 to 24 hours. School glue, a type of white glue, dries more slowly. Inexpensive and nonflammable, PVA glue dries clear.

PVA (white glue) has a low resistance to moisture but a long shelf life.

Epoxy: Epoxies are sold in tubes or in cans. They consist of two parts — resin and hardener — that must be thoroughly mixed just before use. They are very strong, very durable, and very water resistant. Epoxies are recommended for use on metal, ceramics, some plastics, and rubber; they aren’t recommended for flexible surfaces. Clamping is required for about 2 hours for most epoxies. Drying time is about 12 hours; curing time is one to two days. Epoxy dries clear or amber and is more expensive than other adhesives.

epoxy is very strong and waterproof


 

Cyanoacrylate: Also called super or instant glue, cyanoacrylate is similar to epoxy but is a one-part glue. These glues form a very strong bond and are recommended for use on materials such as metal, ceramics, glass, some plastics, and rubber; they aren’t recommended for flexible surfaces. Apply sparingly. Clamping is not required; curing time is one to two days. Cyanoacrylates dry clear.

Contact cement: A rubber-base liquid sold in bottles and cans, contact cement is recommended for bonding laminates, veneers, and other large areas and for repairs. It can also be used on paper, leather, cloth, rubber, metal, glass, and some plastics because it remains flexible when it dries. It is not recommended for repairs where strength is necessary. Contact cement should be applied to both surfaces and allowed to set; the surfaces are then pressed together for an instant bond. No repositioning is possible once contact has been made. Clamping isn’t required; curing is complete on drying. Contact cement is usually very flammable.

contact cement can be used on laminate

Polyurethane glue: This high-strength glue is an amber paste and is sold in tubes. It forms a very strong bond similar to that of epoxy. Polyurethane glue is recommended for use on wood, metal, ceramics, glass, most plastics, and fiberglass. It dries flexible and can also be used on leather, cloth, rubber, and vinyl. Clamping is required for about 2 hours; curing time is about 24 hours. Polyurethane glue dries translucent and can be painted or stained. Its shelf life is short, and it is expensive.

Silicone rubber adhesive or sealant: Silicone rubber glues and sealants are sold in tubes and are similar to silicone rubber caulk. They form very strong, very durable waterproof bonds, with excellent resistance to high and low temperatures. They’re recommended for use on gutters and on building materials, including metal, glass, fiberglass, rubber, and wood. They can also be used on fabrics, some plastics, and ceramics. Clamping is usually not required; curing time is about 24 hours, but the adhesive skins over in less than 1 hour. Silicone rubber adhesives dry flexible and are available in clear, black, and metal colors.

liquid nails can be used for heavy duty construction jobs

Household cement: The various adhesives sold in tubes as household cement are fast-setting, low-strength glues. They are recommended for use on wood, ceramics, glass, paper, and some plastics. Some household cements dry flexible and can be used on fabric, leather, and vinyl. Clamping is usually not required; setting time is 10 to 20 minutes, curing time is up to 24 hours.

Hot-melt adhesive: Hot-melt glues are sold in stick form and are used with glue guns. A glue gun heats the adhesive above 200F. For the best bond, the surfaces to be joined should also be preheated. Because hot-melt adhesives are only moderately strong and bonds will come apart if exposed to high temperatures, this type of glue is recommended for temporary bonds of wood, metal, paper, and some plastics and composition materials. Clamping isn’t required; setting time is 10 to 45 seconds, and curing time is 24 hours.

Don't use a hot-glue gun if the bond will be exposed to high temperatures

We don’t want this article to be too long, so this will be a multi-part series on using adhesives.  Stay tuned and don’t forget to follow us on Instagram and other social media networks!

One Reply to “Using adhesives pt. 1”

  1. Today, while I was at work, my sister stole my apple ipad and tested to see if it can survive a 25 foot drop, just so she can be a youtube sensation. My iPad is now broken and she has 83 views. I know this is totally off topic but I had to share it with someone!

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