I need to attach a relatively small piece of ABS plastic to another. The small piece is about 4 mm wide, 1 mm tall, and I can make it between 3-6 mm long.
I need to attach it so that 1 mm of the plastic hangs out over the edge of the other piece.
This overhang will be subject to regular, small pressure. It's a catch for another piece, to hold it in place. It's not a lot of pressure to hold it, but the pressure of catching and uncatching it can be an issue.
If you look at this diagram, I need to fuse the blue parts, so that the red part can by slid on and off vertically. The red and blue parts that overlap are slightly rounded, and the red has some give, which makes the catching fairly easy.
If it helps, this is for a modification to an action figure. The catch is the kind you'll find on Transformer action figures, which gently hold pieces in place.