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The Filament Price Index

Updated July 22, 2026

Best Filament for Prusa MK4 & Core One

The Prusa MK4 is an open-frame workhorse with direct-drive extrusion and a heated bed capable of printing virtually every common filament type. We break down which materials run best — from PLA to nylon — and what to watch for on an unenclosed printer.

Printer Guide
Prusa Research has long set the standard for reliable, open-source 3D printing, and the MK4 (alongside the newer Core One) continues that tradition. With direct-drive extrusion, a 250 × 210 × 220 mm build volume, and a generously sized heated bed, the MK4 can handle a wide range of thermoplastics. The key limitation is that it is an open-frame printer. While the heated bed reaches 120 °C, the chamber is not enclosed, so materials that require high ambient temperatures or produce strong fumes during printing need extra care. PLA and PLA+ PLA remains the everyday champion for the MK4. The direct-drive extruder handles all PLA variants with ease, and the PEI-coated spring steel sheet provides excellent first-layer adhesion. PLA prints beautifully at bed temperatures of 55–65 °C with nozzle temps around 200–220 °C. For even better layer adhesion and impact resistance, PLA+ is a modest upgrade that prints on the same settings. PETG PETG is where the MK4 truly shines compared to many open-frame competitors. Prusa printers are famous for their reliable PETG profiles, and the MK4 is no exception. The heated bed at 75–85 °C and the direct-drive extruder produce consistent, strong parts. Use a glue stick or textured sheet for better release — PETG can be aggressive on PEI surfaces. TPU and Flexible Materials Direct drive is ideal for flexible materials. The MK4 prints TPU exceptionally well at slower speeds (20–30 mm/s), with bed temperatures of 40–50 °C and nozzle temps of 220–240 °C. You can print soft TPU (Shore 85A–95A) without modifications. For harder grades like 98A, you can even push speeds closer to normal PLA speeds. ABS and ASA ABS and ASA are printable on the MK4 but require careful setup. Because there is no enclosed chamber, you will need to: - Print in a warm, draft-free room or use an enclosure tent. - Use a brim for warping-prone parts. - Keep bed temperature at 100–110 °C. - Expect slower print speeds for better layer adhesion. ASA is preferred over ABS when UV resistance matters (outdoor parts), and it emits less odor. PC (Polycarbonate) and Nylon (PA) The MK4's 120 °C bed and all-metal hotend (up to 290 °C) make it capable of printing PC and PA, though these are advanced materials. PC requires bed temps of 100–110 °C and nozzle temps of 260–280 °C. Nylon (PA) needs bed temps of 80–100 °C and nozzle temps of 250–270 °C. Both benefit from an enclosure and should be dried before printing — moisture ruins their mechanical properties. PLA-CF and PLA-SILK Carbon-fiber-filled PLA (PLA-CF) works well in the MK4's direct-drive extruder, though a hardened nozzle is recommended to avoid abrasive wear. PLA-SILK prints beautifully at slightly higher nozzle temps (210–230 °C) and slower speeds for maximum shine. What about the Prusa Core One? The Core One shares the same extruder design and material compatibility as the MK4 but adds an enclosed build volume and a slightly taller 270 mm Z-axis. The enclosure makes ABS, ASA, PC, and PA printing significantly easier. All of the recommendations above carry directly to the Core One, with even better results for engineering-grade materials.

FAQ

Can the Prusa MK4 print carbon fiber filament?
Yes, PLA-CF prints well on the MK4. However, carbon-fiber-filled filaments are abrasive, so you should use a hardened steel nozzle to prevent wear on the standard brass nozzle. The direct-drive extruder has no trouble pushing the material through.
Does the MK4 need an enclosure for ABS?
Not strictly, but it is highly recommended. ABS shrinks as it cools, causing warping and layer separation in drafty environments. A simple Ikea Lack enclosure or a purpose-built tent dramatically improves success rates. Without an enclosure, keep the room warm (30–35 °C) and free of drafts.
What is the best bed temperature for PETG on the MK4?
75–85 °C is the sweet spot. Some users find that 80 °C provides the best balance of adhesion and release. Apply a thin layer of glue stick or use the textured powder-coated sheet to prevent PETG from fusing to the PEI surface.
Is the MK4 good for TPU?
Yes — the direct-drive extruder is excellent for flexible filaments. You can reliably print TPU at 20–30 mm/s with Shore hardness down to 85A. No modifications are needed; just use the standard extruder with the tension set appropriately.
The Prusa MK4 is one of the most versatile open-frame printers on the market. Whether you are printing functional PETG parts, flexible TPU gaskets, or engineering-grade nylons, the MK4 delivers consistent quality. Just plan accordingly for materials that want a warm, enclosed environment. Browse our current deals on the filaments mentioned above to find the best prices on spools that work with your Prusa MK4.

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