Do you use 3D printing to make functional parts? Do your printed parts have slight dimensional errors, such as undersized holes? It is essential to take care of this if you use your FDM 3D printer to make precise or functional parts. Here’s the easiest and most elegant fix, using nothing but your slicer and a caliper.
Because the extruded molten plastic gets squashed by the nozzle and also flows outward toward the sides, everything you print is fattened, creating overall oversized prints and undersized holes.
Fortunately, there are ways to fix this flaw. First, I would recommend against these methods, if you currently use them:
- Compensating by slightly changing the values in CAD: this is cumbersome if you use different printers or have collaborators, and problematic if you work with assemblies in CAD.
- Changing the size in the slicer: FDM 3D printers generally have undersized ID and oversized OD, so enlarging or shrinking the size is bound to reduce one problem while worsening the other.