Depends on the build, I seen a master builder use a small rubber mallet when making a large display. It was solid after that.
I'm at the mall right now I'll ask for you and get right back to you
Not something that I've ever seen.
Authentic LEGO has strong clutching power that is quality controlled. If you need something stronger than that, I would suggest reinforcing your build with more pieces or a stronger foundation.
I don't think so but I could ask. I only now that works is glue.
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