Update: I had a bad measurement, it came out slightly too large. That has now been corrected... If you printed a full set of 60 degree pieces with the wrong size(like I did), print one with a sector_radius of 291.75 and replace one segment with it. I have uploaded the stl for that as dehydrator-60-100-wrong-size-correction.stl
I bought a spool of filament which appeared to have too much moisture content, so I acquired a Salton VitaPro food dehydrator from Kijiji. I could have cut the bottoms out of the trays to allow my spools to fit, but preferred to leave them intact, and searched for spacers on this site.
This dehydrator has an outer diameter where the layers join of about 12 9/16". I found one I quite liked by Allex Whittemore: https://www.thingiverse.com/thing:3027142
I had a few problems printing it, largely due to the long inside curves, so I decided to make my own customisable version for openSCAD.
You can use the parameters to customise the diameter of the dehydrator, the thickness of the walls, the height, and the degrees of arc per printed section (I personally am using 60 degrees, although I could go bigger on this printer)
I used my own parametric spiral generator to produce the arcs needed: https://www.thingiverse.com/thing:3252949
I had issues printing this without a brim, it even separated from the raft. Brim fixed it, though