3D Printing InfoPrinter comparison
Original Prusa MK4 vs Rat Rig V-Core 4.1
Compare hardware, build volume, printing specifications, dated prices and sources.
2 selected · all documented properties
Open these two in the interactive comparisonMore Original Prusa MK4 comparisonsMore Rat Rig V-Core 4.1 comparisons
| Property | Original Prusa MK4BEDSLINGER | Rat Rig V-Core 4.1COREXY |
|---|---|---|
| Identity | ||
| Brand | Prusa Research | Rat Rig |
| Class | BEDSLINGER | COREXY |
| Identity & Market | ||
| Manufacturer & exact marketed model name (verify the exact product identity first) | Original Prusa MK4[1] | Rat Rig V-Core 4.1, described by Rat Rig as a large-format open CoreXY 3D printer kit[2] |
| Release date (announcement and actual shipping) | Announced 29 March 2023 with assembled printers shipping immediately from stock; kits opened for ordering about two weeks later[1] | Not documented |
| Launch MSRP (USD) | 1099 USD assembled, 799 USD as a kit, VAT included, at launch[1] | Not documented |
| Variants & sibling models — and how to tell them apart (spec-contamination risk) | Superseded by the MK4S, which is the same machine plus a 360-degree turbine part-cooling fan, a high-flow CHT nozzle and firmware/profile work; Prusa sold a 99 USD MK4-to-MK4S upgrade kit and automatically converted unshipped MK4 orders to the S version. The MK3.5 and MK3.9 upgrades convert an MK3S+ to part of the MK4 electronics stack but are not an MK4[3][1] | Three sizes, all at the same base-kit price. Acceleration is the size-dependent figure and the one most often mis-quoted: 15,000 mm/s2 at 300 mm, 12,000 at 400 mm, 8,000 at 500 mm. IDEX is a configuration option and changes the usable area per toolhead (copy mode 150x150x300 at the 300 size, mirror mode 95x95x300). Base kit excludes electronics. Rat Rig prices the base kit only in EUR (EUR 873.90 on sale from EUR 971.00, Aug 2026); no USD list price is published, so no USD street price is recorded here[2] |
| Market position: superseded? successor announced? | Discontinued. No MK4 appears in Prusa's Aug 2026 3D-printer listing, and the MK4 product-page slugs redirect to the MK4S page, so no live first-party price could be recorded[4][3] | Current revision, replacing the V-Core 4; Rat Rig sells a 4.1 upgrade kit for existing V-Core 4 machines[2] |
| Physical & Frame | ||
| Build volume X×Y×Z (mm) — advertised vs actually usable | 250 x 210 x 220 mm (manufacturer figure)[1] | 300 x 300 x 300, 400 x 400 x 400 or 500 x 500 x 500 mm. Sortable value is the 300 mm kit[2] |
| Machine footprint (mm) & clearance needed (cable/spool overhang) | Not documented | 623.2 x 583 x 785 mm (300); 723.2 x 683 x 885 mm (400); 823.2 x 783 x 985 mm (500). Sortable value is the 300 mm kit[2] |
| Net weight (kg) | Not documented | Kit weight 35 kg (300), 45 kg (400), 55 kg (500)[2] |
| Frame construction & material | Die-cast aluminium frame - Prusa replaced the MK3S+'s cut-aluminium frame for the MK4, keeping only the Y-axis profiles, some bearings, the heatbed and the power supply[1] | 30-series aluminium extrusion; the 4.1 adds a steel X-axis gantry for rigidity[2] |
| Enclosure: open / enclosed; panel material; door/lid | Open frame; the Original Prusa Enclosure is an optional add-on[1] | Open frame in the base kit[2] |
| Kinematics & Motion Hardware | ||
| Kinematics (bedslinger i3 / CoreXY / other) | Cartesian bed-slinger of the Prusa i3 family - Prusa's MK4 announcement records that the MK3S+ Y-axis profiles and heatbed were carried over[1] | CoreXY; Hybrid CoreXY and IDEX are configuration options[2] |
| Stepper motors (frame size, step angle, brand if known) | 400-step (0.9 degree) stepper motors, stated by Prusa to prevent vertical fine artefacts[1] | Not documented |
| Stepper drivers (exact model e.g. TMC2209; UART/SPI; sensorless homing?) | Trinamic TMC2130-LA silent stepper drivers on the xBuddy board[1] | Not documented |
| Speed & Acceleration | ||
| Max acceleration (claimed, mm/s²) | Not documented | Size-dependent: 15,000 mm/s2 at 300 mm, 12,000 at 400 mm, 8,000 at 500 mm (manufacturer claims)[2] |
| Extruder | ||
| Type (direct drive / bowden) & design name | Nextruder direct drive with a planetary gear system, 1:10 gearbox ratio; aluminium heatsink, all-metal hotend, no PTFE tube in the filament path[1] | Full-metal skeleton toolhead, new in the 4.1[2] |
| Gear ratio & drive gear material | 1:10 planetary gearbox[1] | Not documented |
| Hotend & Nozzle | ||
| Hotend design (proprietary/standard; quick-swap mechanism?) | Quick-swap nozzle system, 0.4 mm default, other diameters supported[1] | Not documented |
| Max nozzle temp claimed AND firmware max temp limit (both values) | 300 C claimed max hotend temperature in Prusa's MK4 announcement table - note the MK4S product page publishes 290 C for the same hotend family[1][5] | 350 °C maximum nozzle temperature (manufacturer claim)[2] |
| Stock nozzle size & sizes included in box | Not documented | 0.4 mm hardened steel and 0.6 mm included[2] |
| Heated Bed & Surface | ||
| Max bed temp claimed AND firmware limit | 120 C max heatbed temperature[1] | 120 °C maximum heatbed temperature (manufacturer claim). The 400 and 500 sizes get 8 mm thick beds in the 4.1[2] |
| Bed surface (material, texture, coating), single/double-sided | Magnetic heatbed with removable PEI spring-steel sheets; compatible with the MK3 sheets (smooth PEI, satin, textured PEI, PA nylon)[1] | Not documented |
| Leveling & Z-Offset | ||
| Auto bed leveling: probe technology (inductive / strain gauge / load cell / touch probe) | Load-cell sensor: fully automatic first-layer calibration with the nozzle as the probe, plus automatic mesh bed levelling over the print area[1] | Not documented |
| Filament Handling & Detection | ||
| Filament runout sensor (type, location) | Built-in Hall-effect filament sensor supporting automatic filament loading[1] | Not documented |
| Cooling & Air Handling | ||
| Part-cooling fan(s): count, size, ducting design | Not documented | Improved part cooling, listed by Rat Rig as one of the 4.1 changes[2] |
| Electronics & Power | ||
| Mainboard model & MCU (exact chip markings if teardowns exist) | Custom 32-bit xBuddy board with STM32, designed and built in-house, with a separate extruder breakout board[1] | Not documented |
| PSU (brand, wattage, rail voltage) | 240 W Delta PSU with hardware power panic[1] | Not documented |
| Firmware & Openness | ||
| Firmware base & current version (Klipper fork / Marlin fork / proprietary) | Open-source Prusa Buddy firmware. The source tree (prusa3d/Prusa-Firmware-Buddy on GitHub) explicitly covers the Original Prusa MINI/MINI+, MK4, XL and CORE One and was last pushed to in August 2026. Updates are applied from a USB drive, through Prusa Connect or through the Prusa mobile app[6][5] | RatOS 2.1 (Rat Rig's Klipper distribution)[2] |
| Connectivity, UI & Camera | ||
| Display: size, type, touch? | 3.5-inch 65k-colour graphic screen[1] | Not documented |
| On-device UI capabilities (model preview, per-object controls, etc.) | On-device colour UI with one-click printing and status LEDs; Prusa Link is integrated and Prusa Connect adds remote printing[1] | Not documented |
| WiFi (band/standard), Ethernet, USB ports, SD/flash-drive | Ethernet built in, optional ESP Wi-Fi module delivered with the printer, USB drive; print files can also arrive over LAN or the internet via Prusa Connect[1] | Not documented |
| Calibration Routines & QoL | ||
| Assembly level & time from unbox to first print | Not documented | Self-assembly kit; the 4.1 ships pre-made cables that need no crimping, with rewritten step-by-step build documentation[2] |
| Materials Support | ||
| Officially supported filament list | Prusa's launch table says "any thermoplastic including Nylon and Polycarbonate"; the enclosure is still needed in practice for ABS/ASA-class materials[1] | PLA, PETG, ABS, ASA, TPU, PET, PA, PC, PVA, PLA-CF, PETG-CF, ABS-GF, ASA-CF, PA6-CF, PA6-GF, PAHT-CF, PPA-CF, PET-CF[2] |
| Safety | ||
| Thermal runaway protection (verify in firmware source if at all possible) | xBuddy hardware overcurrent protection disconnects heater and heatbed power when total current exceeds 15 A; firmware is open-source and auditable[1][6] | Not documented |
| Reliability, Support & Ecosystem | ||
| Warranty length & support reputation (evidence, not vibes) | 2-year warranty for consumers in the EU, Liechtenstein, Switzerland, Norway and Iceland; 1 year for EU enterprises and 1 year for the rest of the world, which includes the United States. A printer bought from a reseller or privately carries 1 year from the original delivery date and is handled by the reseller. Prusa advertises 24/7 chat and e-mail support in seven languages[7][5] | Not documented |
Manufacturer claims, independent measurements, packages and test conditions retain their source wording. FDM linear speed and resin vertical speed use different units and are not directly comparable. Unknown values are marked “Not documented”. Prices and source dates remain historical snapshots; check the linked guide for product details. Differences highlight text, not a universal winner.
Sources for this comparison
- Prusa blog - Original Prusa MK4 is here (published 29 March 2023), including the MK4 specification table and launch prices blog.prusa3d.com · 2026-08 · doc
- Rat Rig V-Core 4.1 product page ratrig.com · 2026-08 · vendor
- Prusa blog - The Original Prusa MK4S is Here! (published 12 August 2024) blog.prusa3d.com · 2026-08 · doc
- Prusa 3D printers category listing with live e-shop prices, Aug 2026 prusa3d.com · 2026-08 · vendor
- Original Prusa MK4S 3D Printer product page (Technical Parameters + CORE One+/MK4S/XL comparison table) prusa3d.com · 2026-08 · vendor
- GitHub - prusa3d/Prusa-Firmware-Buddy (firmware for MINI, MK4, XL and CORE One) github.com · 2026-08 · doc
- Prusa Knowledge Base - Warranty help.prusa3d.com · 2026-08 · doc