PLA the easy way

How to glue PLA: best adhesives for this renewable plastic

3D printing is taking the manufacturing world by storm. Learn how to glue PLA like a pro. We’ll show you the best adhesives and methods for flawless bonds.

How to glue PLA together 

PLA has become a very popular plastic for 3D printing, packaging, and many other applications due to the low cost of manufacturing and its biodegradability. Rather than being petroleum-based, like most other plastics, PLA is made from organic sources. Corn starch, sugar cane, and similar renewable materials are used to produce this more eco-friendly product.

PLA is one of the most common materials used in 3D printers. Its high strength and low melting temperature make it ideal for this purpose. So if you own a desktop 3D printer, you likely use PLA.

At times you may need to join 3D parts together or repair a broken item so you need to know how to glue PLA. Fortunately, the best adhesives for gluing a PLA 3D print are easy to find.

The two most common adhesives for PLA are super glue and epoxy. However, there are many variations of these adhesives, so you will have to choose one that is compatible with PLA. (We have some recommendations below.)

For most applications, super glue is going to be your DIY go-to as it has several advantages over other types of adhesives, to name a few:

  • Very strong hold
  • Simple to use
  • Quick application and dries fast
  • Dries transparent for a professional-level finish
  • Economical choice

How to glue PLA 3D print: simple instructions

Once you have chosen the best adhesive for your project, follow these simple instructions to permanently glue your PLA parts together.

  1. Wear safety gear. Always wear latex or nitrile gloves and eye protection when working with adhesives. Also, prepare your work area in a well-ventilated and adequately lit area.
  2. Gather your tools and materials. Have your PLA parts, adhesive, and supplies close at hand. You may need sandpaper, some paper towels or clean cloth, and a means to hold the parts together until the glue dries, such as a clamp, masking tape, or weighty object. Also, have warm, soapy water and some acetone available.
  3. Pre-fit your parts. Make sure the parts are close-fitting, clean, and dry. Smooth or shiny surfaces should be lightly sanded to improve adhesion. For the best results, use fine sandpaper such as 220 grit.
  4. Apply the adhesive. Use a small amount of glue on one of the PLA surfaces.
  5. Immediately press the PLA parts together and hold them in place for 30 seconds to a minute. The glue will set quickly, so ensure the parts are correctly positioned.
  6. Allow to dry. Allow 24 hours for the glue to fully cure before handling the object.
  7. Clean up. Re-cap the glue and clean your tools and work area immediately with soap and water.

Have some excess glue on your PLA print? No problem. Here is how to remove it:

  • Uncured adhesive: if you catch it before the glue sets, use a sponge or soft cloth soaked in warm, soapy water to wipe it away.
  • Cured adhesive: if the glue is dry, use acetone (nail polish remover) on a clean cloth. Always test the acetone on an inconspicuous part of the object first since, in some cases, it may cause discolouration.

Best way to glue PLA: our recommendations 

Your go-to product to glue PLA and other plastics is Loctite Super Glue All Plastics. This special two-step formula is designed to form resilient, permanent bonds to plastic surfaces, including even those that are typically hard to glue. It sets in just seconds and is nearly invisible once dry. 

The two-step process is simple. Apply activator to both surfaces and wait 60 seconds. Then apply the glue to one surface and join the parts. It can also be used on porcelain, metal, rubber, and more.

Another option is Loctite Super Glue Power Gel Control. This is the best choice for applications that will be subjected to frequent vibration, impact, or stress. The rubber-infused formula creates a powerful bond in just seconds yet remains permanently flexible. It’s water and weather resistant and dries transparent.

If you need the extra strength and gap-filling properties of an epoxy, you’ll love Loctite Epoxy Plastic Bonder. Specially formulated to bond and repair plastic surfaces, it will form a rigid bond in about 20 minutes. The double-syringe applicator makes mixing easy and precise. Once fully cured, the epoxy is resistant to water and most solvents and can be sanded and drilled.