Adhesives

Plastics

3D Printing Materials

When working with 3D printed parts, choosing the right adhesive is crucial for achieving strong and reliable bonds. Here are some common types of adhesives that are suitable for use with 3D printed parts:

Hot glue is useful for joining parts impermanently. This is great for prototyping.
For PLA or ABS:
- Adhesives:
  - Super Glue (Cyanoacrylate): Wear gloves!
  - Two-part epoxy: For a stronger bond.
  - Welding with Acetone (ABS only): Although not exactly a glue, it works by dissolving the plastics allowing them to merge. If used properly, the seal is basically invisible and the bond is very strong.
  - E6000: Creates a very strong bond and can be used to bond plastics to metal or wood.
  - Silicone glues (Loctite, Permatex)
- Tips: Sanding and scoring the surface improves adhesion.
PETG:
- Adhesives:
  - Super Glue (Cyanoacrylate): Wear gloves!
  - Two-part epoxy: For a stronger bond.
  - Plastic Bonder (e.g., JB Weld Plastic Bonder)
- Tips: PETG has a smooth, non-porous surface, so roughing it up helps.
Nylon
- Adhesives:
  - Two-Part Epoxy (e.g., JB Weld)
  - Hot Glue (for temporary bonds)
  - Plastic Bonder Adhesives
- Tips: Nylon resists adhesives; heat-welding or mechanical fasteners are often better.
Markforged Onyx (Nylon + carbon fiber):
- Loctite 401 for bonding to other Onyx parts
- Scotch-Weld DP100 for bonding Onyx to metal, glass, stone, various plastics
- Scotch-Weld DP100Plus for bonding Onyx to metal, ceramics, glass, many plastics
TPU:
- Adhesives:
  - Contact Cement (e.g., Barge Cement)
  - Polyurethane glues (Gorilla Glue)
  - Rubber Cement
- Tips: Avoid super glue if high flexibility is needed.
Polycarbonate (PC)
- Adhesives
  - Two-Part Epoxy
  - Super Glue (Gel-type)
- Tips: Roughen the surface for better adhesion.
Resin prints:
- Adhesives:
  - Cyanoacrylate glues (super glues)
  - UV Resin (Cure with UV light for seamless joints)
  - Acrylic cement
- Tips: Using uncured resin and curing it under UV light creates an invisible bond.
Structural Adhesives: Some manufacturers offer structural adhesives specifically formulated for bonding 3D printed parts. These adhesives are designed to provide high strength and durability, often suitable for load-bearing or structural applications. They may come in various forms, such as two-part epoxy, cyanoacrylate, or hybrid formulations.
Specialty Adhesives: Depending on the specific requirements of your project, you may also find specialty adhesives tailored for certain materials or applications. For example, there are adhesives designed specifically for bonding nylon, polycarbonate, or other engineering-grade filaments commonly used in 3D printing.
Like with wood and other materials, designing proper geometric joints will offer greater strength than glue alone. See this video on Joint examples for splitting up your part for printing. Combining the right kind of joint with an adhesive appropriate for the applicaiton is ideal

Other Plastics

Polypropylene (PP)
- Best Adhesives:
  - Polypropylene-specific glues (e.g., Loctite Plastics Bonding System)
  - Hot-Melt Adhesives (some industrial-grade hot glue works)
  - Two-Part Epoxy (with plastic primer)
- Best For: Low-energy surfaces that resist most glues.
- Tips: Use a flame treatment (briefly pass a flame over the surface) to improve adhesion.
Polyethylene (PE, HDPE, LDPE)
- Best Adhesives:
  - Plastic Welders (e.g., 3M Scotch-Weld DP8005)
  - Hot-Melt Adhesives (high-performance variants)
- Best For: Containers, plastic bins, and chemically resistant applications.
- Tips: Polyethylene is notoriously difficult to bond—mechanical fasteners are often better.
Carbon Fiber Composites
- Best Adhesives:
  - Two-Part Epoxy (JB Weld, 3M DP420)
  - Polyurethane Adhesive (e.g., Gorilla Glue)
- Best For: High-strength applications.
- Tips: Ensure clean, dust-free surfaces before bonding.
Acrylic (PMMA, Plexiglass)
- Best Adhesives:
  - Acrylic Cement (e.g., Weld-On #4)
  - Super Glue (for small repairs)
- Best For: Clear plastics.
- Tips: Avoid fogging by using solvent cements instead of super glue.

Rubber (Natural & Synthetic)

**Rubber
- Best Adhesives:
  - Contact Cement (Barge Cement)
  - Super Glue (for rigid joints)
  - Rubber Cement (for temporary bonds)
- Best For: Flexible and stretchable materials.
- Tips: Clean with isopropyl alcohol before applying glue.

Glass

Best Adhesives:
- UV-Curing Adhesives (for clear bonds)
- Silicone Adhesive (for flexibility)
- Epoxy (for strength)
Best For: Transparent or load-bearing applications.
Tips: UV glue provides the cleanest, strongest bond.

Metal

Metal (Aluminum, Steel, Copper, etc.)
- Best Adhesives:
  - Metal Epoxy (JB Weld, Devcon)
  - Cyanoacrylate (for quick fixes)
  - Polyurethane Adhesive (for bonding to porous surfaces)
- Best For: Structural bonds.
- Tips: Roughen the surface before applying glue.