I want to print a working prototype of an item that will eventually be mass-produced, made of molded plastic.
My main question: is it possible for the printing process to be stopped part of the way through for magnets to be placed in a trench in the model, then the printing would continue until the magnets are completely covered? Or should I just model 2 parts that can be glued together later with the magnet inside?
It's possible on your own printer. Not through shapeways. I watched a video of printing a battery with a makerbot (I think) where they stopped it a few times to add components. This could be very hazardous to your print head!Your friendly neighborhood Moderman
Have a look at the video linked from the "How it works" in the footer of the shapeways web pages. The processes used
are completely different from what reprap-style homebuilt machines do, also as many models as possible are printed
in the same run. Either create separate parts that you can glue together around the magnets, or perhaps design slots
where you can insert them.