I haven't actually got a printer at the moment. Weirdly, working with them day in day out makes me not want to see them in my personal time and I've got rid of most of that and gone low-tech at home. I do have a mitre saw though.You could of course 3D print the mould in sections...
Yes ^^^ have seen this in steel concrete forms, and yes they apply a piece of tape every tine.I've never done it but I've seen people have tiny air holes in the top so they can blow them out with a compressor
I guess when you re-use it you need to stick a bit of tape over the hole so it doesn't fill up