Adhesives


Adhesives

What Are Adhesives?

Adhesives are bonding agents used to hold materials together, temporarily or permanently. They're used in woodworking, construction, automotive, home repairs, and crafts. Choosing the right adhesive is just as important as choosing the right fastener. Use the wrong one, and the bond may fail under stress, heat, or moisture.

Types of Adhesives and Their Uses

White Glue (PVA)

  • Best For: Wood, paper, cloth, porous surfaces
  • Set Time: Slow to medium
  • Strength: Good
  • Notes: Interior use only, not water-resistant, easy to clean up

Yellow Glue (Carpenter’s Glue)

  • Best For: Wood, soft surfaces
  • Set Time: Faster than white glue
  • Strength: Very good
  • Notes: Slight water resistance, commonly used in woodworking

Liquid Hide Glue

  • Best For: Wood furniture and repairs
  • Set Time: Slow
  • Strength: Very strong
  • Notes: Excellent for antique restoration, reversible with heat/moisture

Polyurethane Glue

  • Best For: Wood, metal, stone, ceramics
  • Set Time: Fast
  • Strength: Very strong
  • Notes: Expands as it cures, water-resistant, wear gloves (sticky)

Construction Adhesive

  • Best For: Subflooring, drywall, paneling, molding
  • Set Time: Slow (can take 24 hours)
  • Strength: Very strong
  • Notes: Thick, fills gaps well, excellent for rough surfaces

Contact Cement

  • Best For: Laminates, veneers, rubber, leather
  • Set Time: Immediate
  • Strength: Strong (once contact is made)
  • Notes: Apply to both surfaces, let dry, then press together. Not repositionable.

Hot Glue (Glue Gun)

  • Best For: Crafts, temporary holding, plastics, wood
  • Set Time: Seconds
  • Strength: Low to medium
  • Notes: Quick fix option, not structural, weak under heat

Two-Part Epoxy

  • Best For: Metal, tile, fiberglass, concrete, plastics
  • Set Time: Varies (5 min to several hours)
  • Strength: Extremely strong
  • Notes: Very durable, chemical-resistant, sandable and paintable

Super Glue (CA or Instant Adhesive)

  • Best For: Non-porous surfaces like ceramics, glass, hard plastic
  • Set Time: Seconds
  • Strength: Very strong but brittle
  • Notes: Not good for flexing materials, small bond area, dries out fast in tube

Other Considerations When Choosing Adhesives

  1. 1
    Flexibility - Some adhesives dry brittle (like CA glue), while others can flex (like construction adhesive or polyurethane). If your materials expand and contract, go for flexible.
  2. 2
    Moisture and Heat Resistance - If the bond will be exposed to weather or high heat, avoid white glue or hot glue. Epoxy, polyurethane, and construction adhesive are better options.
  3. 3
    Open Time and Set Time - Open time is how long you can adjust pieces after applying. Set time is how long it takes to form a bond. Fast-setting adhesives are great for speed, but you’ll have less room for error.
  4. 4
    Paintability and Sandability - If the adhesive will be part of a finished surface (like in trim work), you’ll want one that can be sanded and painted, such as wood glue or epoxy.
  5. 5
    Gap Filling - Some adhesives like epoxy, polyurethane, and construction adhesive can fill gaps. Others, like contact cement and super glue, require tight-fitting joints.
  6. 6
    Clamping Requirements - Many adhesives require clamping during cure time. Know how long and how much pressure is needed to get a strong bond.

Common Adhesive Mistakes

  • Using wood glue on painted surfaces (won’t bond well)
  • Applying too much glue (can weaken the bond or delay cure)
  • Not cleaning the surface first (oil, dust, or moisture can ruin adhesion)
  • Using indoor adhesives outdoors
  • Expecting instant strength—many adhesives take time to fully cure

Final Thoughts

Adhesives aren’t one-size-fits-all. Take a few minutes to understand your materials, your environment, and how much time you have to work with. That will help you pick the adhesive that holds up, finishes clean, and makes the job easier, not harder. Keep a few different types on hand so you’re ready no matter what the project throws at you.