PETG vs PCTG

PETG is the workhorse of functional 3D printing. It is widely available, supported by established slicer profiles and usually priced below PCTG. For many brackets, enclosures and tool holders, it is the practical starting point. Check the named filament's data sheet and test the printed part when impact, heat, UV or chemical exposure matters.

PETG also has the advantage of a massive community. Every printer has a tuned PETG profile. Every filament brand sells PETG. If you run into stringing or adhesion issues, there are thousands of forum posts with solutions. That ecosystem matters when you are troubleshooting at midnight.

Best suited to: general functional printing, prototypes and mechanical parts where availability, profile support and price matter most.

PCTG is a related copolyester family, not simply PETG with CHDM added. PETG itself commonly uses CHDM or another glycol comonomer; the comonomer balance and properties vary by grade.[5] Some high-impact copolyester resin grades publish much higher molded-specimen impact values than a PETG resin grade, but those unlike-grade figures do not establish a category-wide multiplier or predict an FFF part.[2][3]

PCTG is sold by fewer filament brands and often costs more. Its temperature range can overlap PETG, while heat performance varies substantially by grade and test load. For example, Spectrum's PCTG filament sheet reports heat deflection temperatures of 76 °C at 0.455 MPa and 64 °C at 1.82 MPa.[4] Start with the filament maker's range, dry the spool, then tune temperature, flow and retraction rather than applying a fixed offset.

Best suited to: projects where a named PCTG grade documents a needed property and a representative printed-part test confirms it. Clear resin can have excellent optical data, but FFF layer interfaces, pigments and geometry still affect transparency. A resin or filament family name also does not make a print food-safe; certification, additives, nozzle history and the porous printed surface all matter.[6]