I’m making a 3D printed figurine/trophy for my friend as a gift, and I need to glue together base and the figurine itself (it’s a giant amongus). My question is: is something like an instant glue, or just regular glue good enough for PLA, or do I need to by some special one?
Generally any kind of superglue will be fine. Elmer’s glue might even work if you’re in a rush or don’t have other materials. There will be a visible seam, and my experience with both is that it’s quite easy to break the bond (especially with Elmer’s glue).
What you really want is plastic cement or something that’ll melt the plastic slightly, as that’ll give a stronger bond. Plastruct is what I use, but there may be alternatives in your region. This will also leave a seam, but the strength is far stronger than regular glue.
Another way is to do what cosplayers do and use a soldering iron to melt the plastic together (do this in a well-ventilated area). This’ll leave a seamless finish without any visible gaps, but only really works on larger models that you’re also planning to coat/sand.
Having done this, you can also get a “3D pen” that will work with your filament and that’ll work decently well for small areas, and you can also use it to fill in gaps. Overheat the PLA a bit and work fast.
Plastruct has a few different variations but at least the Bond-2 Bondene Cement is a mixture of Dichloromethane and Methyl acetate (MSDS report), and Dichloromethane is one of the best solvents for PLA. It is also absolutely horrible stuff and you really need to be quite careful when handling it.