experimenting with PLA glue

Experimenting with PLA glue

I’ve been having trouble gluing PLA parts together reliably., so I decided to do a brief experiment.

In researching the topic, I haven’t yet found a glue company that explicitly claims their glue is good for PLA (Polylactic Acid filament). Lacking that, I’ve found a few recommendations from other 3D printing fans: Loctite Super Glue Ultragel Control; Gorilla Original Gorilla Glue Minis; Duro Super Glue.

The photo above shows the results of my informal test of these three glues on a PLA joint:

  • The Loctite Super Glue Ultragel Control never formed a good bond. I’m not sure why.
  • The Duro Super Glue worked fine, producing a very strong bond.
  • The Gorilla Original Gorilla Glue Minis formed a good joint to begin with, then, a day later, it easily broke off. Again, I’m not sure what the problem was.

My other experience with Super Glue in general is that it works great for bonding surfaces that are relatively smooth. That is, it doesn’t fill in the small gaps that 3D printed parts often have. This works fine when you’re bonding one surface that was printed on the print bed with another printed on the print bed; I’ve had bad luck gluing the rough surfaces that weren’t printed directly on the print bed.

Meanwhile, another technique I’d like to try is Friction Welding, which sounds very promising.

So it looks like for now Super Glue is the glue to use for PLA, but I’m still searching. In particular I’d love to find either a chemist who can say what glues are perfect for PLA, or an ad that claims this glue works great with PLA.

UPDATE: after asking members of our local 3D Printing Meetup what glue they like, I’ve now settled on E6000, which glues slightly rough surfaces, sets up in about an hour, doesn’t discolor the plastic like Super Glue can, dries clear unlike Gorilla glue, and makes a strong, slightly flexible bond.