How to glue 3D prints: Techniques for bonding and repairing

As 3D printers become more popular, there is a growing need for information on how to join parts and complete repairs. Here are some basic considerations before you begin your work.

You will need to choose an adhesive compatible with the material the print is made of. It will also need to stand up to the conditions the item will be subjected to.

For rigid plastics such as ABS, PLA, and PETG, most types of super glue will work very well. Super glue creates a powerful bond and dries quickly, so it is generally a good choice.

Plumber’s cement will work on 3D prints made of ABS, PLA, and HIPS, but it is unsuitable for nylon, PETG, or similar filaments.

If your 3D print is made of a flexible material, be sure to choose a flexible glue. Other considerations include drying to a transparent finish and gap-filling ability. We will list some recommendations for each of these below.

Here is a handy checklist to help you gather everything you will need: 

• cleaning solution to remove dirt or residue from your 3D prints
• clean cloth or paper towels
• sandpaper
• clamps (if needed) or tape to hold the bonded items together
• solvent for cleanup (see manufacturer’s directions)
• utility knife or razor blade
• adhesive

Remember to wear protective gear such as nitrile gloves, safety glasses, etc. Always work in a well-ventilated area when using adhesives.

Here are the basic steps to glue 3D prints together. Some steps may not apply in all situations.

1. Clean the surfaces to be bonded. Ensure they are free from dust or residue and fit closely.
2. Sand the surfaces if they are shiny or very smooth. (This is true in most cases, but please consult the product’s instructions.)
3. Prepare the adhesive. When using epoxy, mix it in the proper proportions. If using hot melt glue, begin heating the applicator. 
4. Apply the glue. Follow the glue package instructions regarding the amount, drying time, and whether to apply to one or both surfaces.
5. Join the surfaces. Press the parts together, making sure they are positioned correctly, and keep them in place until a bond forms. Clamp or tape the pieces together if necessary.
6. Allow the glue to set completely before using the object.
7. Clean up. Use a paper towel or cloth and the recommended solvent to clean up drips or excess glue around the seams. (Most often this will be acetone or mineral spirits.) If the adhesive has hardened, use a razor blade to remove it.

Here are our recommendations for adhesives that will cover most situations.

Loctite Super Glue Control is often a perfect fit for joining parts and repairs. This versatile adhesive dries quickly to form a strong bond and is nearly invisible when dry. It is resistant to shock, water, and extreme temperatures. Super glue control is available in your choice of applicators: easy-grip, long nozzle, and brush-on.

If a flexible adhesive is needed, try Loctite Super Glue Power Gel Control. It contains a unique rubber-infused formula that creates powerful bonds yet remains flexible. It is resistant to weather and shocks and dries transparent for invisible repairs. The glue bonds in seconds to most types of plastic, making it ideal for gluing 3D printed parts! 

You’ll want to use Loctite Epoxy Instant Mix 5 Minute when you need epoxy’s super strength and gap-filling qualities. Consisting of an epoxy resin and a hardener which are mixed in equal volumes, the adhesive will form a rigid, high-strength bond to most plastics as well as china, tile, fiberglass, and concrete. It is perfect when the parts don’t fit as tightly as they should because it can span large gaps without cracking or shrinking. This epoxy is easily dispensed from the dual syringe and begins to set in just 5 minutes. It can even be tinted to match the surrounding materials.