- nip.jpg (140.29 KiB) Viewed 7072 times
That's the latest prototype and the first with all holes clear. My views on printing Nipkow discs are that the hole size is never going to be consistent. What I'd be doing if I were trying to make a disc to use would be to have holes in the first few layers, very tiny. If they're filled in that's OK, because the slicer puts boundary circles of filament around where the holes are. Very obvious under magnification. I'd print the majority of the disc as a solid (no holes, at least no scanline holes). Then I'd post-process the disc by pushing a hot pin through where the hole positions are clearly marked, or by drilling. You'd have a consistent size and pretty accurate positioning, IMHO.
With so many holes, the pattern of printing is complex, and the disc isn't "smooth". With just the first few layers having the holes, this can be avoided and get a much better and structurally sound disc print. I'll do one soon and see how it works out. That is, shallow holes for just the first few layers, and then solid for the rest. Use a dremel to drill out to exact size - given a really precise position already marked by the printer first few layers.