Yes, in theory 3D printing can achieve bilateral tolerances for shafts and holes in RC cars, but the precision depends heavily on the type of 3D printing technology used, the material, and post-processing techniques.
FDM is commonly used for hobbyist 3D printing, but it typically has lower precision due to layer lines and potential issues like warping. Achieving tight tolerances (especially under 0.1mm) can be challenging without significant post-processing. Techniques such as sanding, drilling, or reaming can help achieve better tolerance fit. Sometimes you may even need to print slightly undersized or oversized parts, then manually adjust them to the precise tolerance required.
For hobby-grade RC cars, FDM printers can usually achieve tolerances around 0.2mm–0.3mm, which may be acceptable for non-critical components. HOWEVER, for functional RC car components (like shafts, gears, or wheels), a tighter tolerance of 0.05mm–0.1mm is often necessary. This may be achievable with SLA, SLS, or MJF printing technologies, combined with careful design and post-processing.