Tinmorry PETG-GF Filament 1.75mm 1kg

PETG with glass fibre through it, in 22 colours. The fibre does two things: it stiffens and hardens the print, and it kills the shine — you get a fine frosted matte surface that hides layer lines better than almost anything else at this price.

What makes it stand out on paper is how little it gives up in the Z axis. Tensile strength is 51 MPa across the layers and 41 MPa along them, so roughly 80% retention — unusually good for a filled filament, where a third of the strength disappearing in Z is normal. Parts behave more predictably however you orient them.

At a glance

Worth knowing

Hardened steel, and 0.4mm minimum. Tinmorry require a hardened nozzle and list 0.4, 0.6 and 0.8mm as compatible — a 0.2mm nozzle is not. Glass fibre is abrasive and will wear a brass nozzle noticeably faster than plain PETG.

Strong across the layers, and tough with it. 30.8 kJ/m² Charpy impact in X–Y and 9.1 kJ/m² in Z, with 89 MPa bending strength. Combined with the good Z retention, this is a sensible choice for functional parts where you cannot control print orientation perfectly.

Do not bother annealing it. Tinmorry state plainly that annealing only raises strength, stiffness and heat resistance slightly, and that some prints may shrink or deform in the process. The gain is not worth the risk — print it and use it.

Glass fibre can irritate skin. Tinmorry note it may cause an allergic reaction in some people and suggest wearing gloves when handling the filament. Worth knowing if you are sensitive, and worth a thought before sanding a print.

Heat resistance is ordinary PETG territory — 71°C glass transition, 73°C heat deflection at 0.45 MPa, 68°C at the heavier 1.82 MPa load. The glass fibre buys stiffness and dimensional stability, not temperature. Printing is odourless, and it resists water, most oils and greases, and weak acids and alkalis; strong acids, strong alkalis and some organic solvents will attack it.

Storage

Tinmorry specify drying at 65 ± 5°C for at least 8 hours before printing, and keeping humidity under 25% while you print. Store below 30°C and under 20% RH, sealed with fresh desiccant. The spool itself is ABS and only rated to 80°C, so do not dry it hotter than specified — and never in a kitchen oven or microwave.

As filament takes on moisture you'll hear popping or hissing at the nozzle, then see stringing and rough surfaces, and eventually the strand goes brittle enough to snap in the tube. That's almost always moisture, not technique — dry it and it usually comes back.