Blog

PLA Glue Sticks

Achieving seamless perfection on your 3D prints can be tricky, especially when it comes to joining separate pieces. Traditional methods often leave behind unsightly seams or struggle to create truly strong bonds. The humble "glue stick hack" offers a surprisingly effective solution.

Read Tip: The Ultimate Bonding Guide

By applying a thin layer of your PLA glue stick to the bonding surfaces before printing, you can create invisible welds that hold your creation together, taking your 3D prints to the next level.

The Process in Action

Just like a regular glue stick, heat up the PLA filament in your hot glue gun. Once molten, apply the PLA to the interior seams where the two 3D printed parts meet. Then allow the PLA to cool completely, creating a strong and invisible connection between the parts. 

It's important to acknowledge the limitations of this hack:

    • Temperature: Standard hot glue guns typically operate at lower temperatures than what's ideal for melting PLA effectively. While high-temperature options exist, they're less common and more expensive.
    • Feeding the PLA Glue sticks: Hot glue guns rely on a feed mechanism designed for grabbing standard glue sticks. The smooth, hard surface of PLA filament can make it difficult for the mechanism to grip the "glue stick" properly.

Let's ensure safety first! While the glue stick itself isn't inherently dangerous, it's always a good practice to wear gloves to avoid any skin irritation. Additionally, work in a well-ventilated area to minimize inhaling any dust or fumes from the 3D printing process.

Now, for the invisible bond magic! Apply a thin, even layer of the glue stick to the bonding surfaces. A light touch is key – you only need a very thin film. Once your prints are complete, the true test is in the flexibility of the bond. If the parts come together securely with a slight wiggle but resist pulling apart, you've achieved a successful invisible weld!

Workarounds

Here are some solutions to get your PLA "glue stick" working:

  • Sanding is Key: To help the feed mechanism grab the PLA, try sanding the filament lightly before inserting it into the hot glue gun. This creates a textured surface for better gripping. Another option is to print ridges into the PLA stick. 
  • The Blob and the Bump: While you can simply deposit a blob of molten PLA and press the parts together, this might leave a visible bump at the joint. The PLA cools and hardens quickly, limiting its ability to spread smoothly.
  • Download our new Glue Gun Ribbed Stick:  Made from leftover bits of filament, these ribbed sticks can be used to fix or glue your 3D printed parts. The ridges in the stick make sure your glue gun has enough grip! 

It's important to note that molten PLA doesn't create a true weld on a molecular level. Instead, it forms a strong bond by slightly melting the surfaces it touches and filling in any gaps. Think of it as a "pseudo-weld" – strong enough for most applications, but not a perfect fusion.

Using PLA filament as a "glue stick" in your hot glue gun is a clever hack with its fair share of creativity. While it won't create a true weld, it offers a unique way to achieve strong, hidden bonds within your 3D printed creations. Just remember the temperature limitations and potential for bulk at the joint. With a little ingenuity, you can unlock new possibilities for joining your 3D printed parts!