With a build volume of 320 x 320 x 400 mm, the Mingda Rock 3 3D printer offers a large format FDM printing experience that is typically not found at the sub – $500 price point, with many common aftermarket upgrades installed at the factory. The silent stepper motors, dual Z leadscrews, and direct drive extruder all come together to create a machine that is able to print large parts quickly, quietly, and repeatedly.
Mingda Rock 3 Specifications:
– Extruder: .4mm Nozzle
– Heated Bed: 0-90 degrees C
– Build Volume: 320 x 320 x 400 mm (12.6” x 12.6” x 15.75”)
– Materials: 1.75mm Filament (PLA, PETG, TPU, etc.)
– Connectivity: USB / SD Card
– Interface: 3.5” Color Touchscreen LCD
– Dual Z Threaded Rods
– Direct Drive BMG Clone Extruder / v6 Clone Hot End
– TMC2208 Silent Stepper Motors
3D Printer Assembly and Review
The Mingda Rock 3 ships with all required tools and hardware for assembly and doesn’t require any wiring, soldering, or any complex process beyond the abilities of a beginner. The base of the printer has the Y-axis pre-assembled, with the belts pre-tensioned and all of the wiring connected internally. The base of the Rock 3 measures 22” x 16.5”, so you’ll want to make sure you have a large enough surface to accommodate it.

(Photo: Andrew Sink)
The Rock 3 includes an SD card, USB cable, allen keys, a leveling card, and a basic assembly guide to get the user off to a quick start. Assembling the printer is similar to other aluminum extrusion machines; just attach the X/Z gantry to the base, secure the bolts, and connect the endstops and Z motors.
Direct Drive Extruder

(Photo: Andrew Sink)
One of the key features of the Mingda Rock 3 is the extruder and hot end assembly. The Rock 3 uses a Bondtech BMG clone extruder coupled with a v6 clone hot end. This is an interesting configuration, and is typically found as an aftermarket upgrade on most machines. This lightweight configuration allows for faster travel on the X-axis while not requiring the long retraction moves typically associated with a Bowden extruder setup. Just like the Mingda D2, the Rock 3 has a color-changing LED attached to the assembly that lights up the area directly under the hot end, and is useful for seeing how the layers are adhering.
Large Volume 3D Printing

(Photo: Andrew Sink)
The build volume of the Rock 3 is 320 x 320 x 400mm (12.6” x 12.6” x 15.75”) which allows for the printing of large parts in a single print. Leveling the platform in the X/Y plane is achieved by adjusting the four large thumbscrews at each corner of the build platform manually. The build surface is a flexible magnetic mat that adheres solidly to the magnetic base, and is easily removed by peeling it off. Parts are easily removed from the mat by gently bending and allowing the part to pop off.

(Photo: Andrew Sink)
First Prints – Mingda Gcode Files
The Rock 3 comes with an SD card that includes a quick installation guide, a .exe installer for RepetierHost 2.1.6, several STL files, and a folder with pre-sliced .gcode files for test printing. For my first print, I printed the “Round vase.gcode” to see how these files were prepared. For this test print, I used Fillamentum “Vertigo Galaxy” PLA material.
Just like some of the test prints included with the Mingda D2, this file was prepared with a large raft, many solid layers, and took nearly 12 hours to print. It was also sliced with each layer reversing direction after completing, which caused a seam up the side of the mode. I would definitely recommend skipping the included demo prints, as the quality isn’t representative of what the machine can accomplish, and the 12 hour build time is excessive for a first print.

(Photo: Andrew Sink)
Slicing Software: RepetierHost vs PrusaSlicer
The Rock 3 ships with RepetierHost 2.1.6 by default, which can be a little confusing for new users who are expecting a more well-known printer preparation software like Cura. I personally use PrusaSlicer for almost all of my printers, so I used the included gcode files to create a profile in PrusaSlicer that would work with the Rock 3.

(Photo: Andrew Sink)
To test out the slicer software, I printed the Apollo Astronaut by Charlie1982 at .2mm layer height using Printed Solid Jessie ‘Beige 500’ PLA. The model printed out clean and without issues, and the built-in supports snapped off easily but left visible marks. The printed model has some light banding and other visible artifacts, which indicate the machine will require some dialing in with the new slicing software.
3D Printing with Full Z Axis Height – Filament Runout Sensor
While running some test prints, I noticed a strange design issue on the Rock 3 that needs to be addressed if you’ll be printing parts at the full 400mm Z height. The filament run-out sensor is located on the X/Z gantry, and is located behind the extruder assembly on the Y axis. This means that filament passing through the runout sensor also needs to curve forwards towards the extruder assembly, which causes an S-curve shaped pinch point when the extruder raises on the gantry. If printing a model above 350mm, this curve can be challenging for brittle or composite filaments, and the runout sensor is actually lower than the filament input when the gantry is maxed out at 400mm. There are two easy solutions: A) disable the filament runout sensor and B) bypass the sensor by placing a piece of filament in it and run the material directly into the extruder. A better solution would be to develop a bracket that pushes the sensor up in Z and forward in Y, which would allow the sensor to be used even with full height prints.

(Photo: Andrew Sink)
Should you buy the Mingda Rock 3?
The Mingda Rock 3 offers a lot of features that are useful to any potential user who is hoping to print large items with a direct drive extruder and easily remove them from the build platform. The silent stepper drivers and dual Z leadscrews help to push this printer to a higher level of performance, but experienced power users may be disappointed with the lack of an automatic bed leveling device. The manual leveling process works well and is relatively quick but could likely be removed altogether with the addition of a probe to measure Z offset distance. Aside from a few minor design quirks, the Rock 3 is a great value considering it’s sub-$500 price point, and includes upgrades that will benefit any user who purchases one.

(Photo: Mingda)
Source & Links
- MINGDA Official Website
- MINGDA DIY 3D Printers – D2, D3, D4
- MINGDA Rock 3 FDM 3D Printer on Amazon (affiliate link)
- MINGDA D2 FDM 3D Printer on Amazon (affiliate link)
Read More & Compare: Desktop 3D Printers
Choose a desktop 3D printer that is right for you. Build volume, FDM or SLA, well-known brand or a start-up – all to consider. The table helps to compare and make a comprehensive decision. It is regularly updated and maintained.
2 thoughts on “Mingda Rock 3 3D Printer Review: Large Volume 3D Printing Under $500”
Hi, ive bought the Rock 3 some days ago and now i wanna ask you if u could share your PrusaSlicer profile for this Printer with me ?
Hi Jari!
Happy to share my PrusaSlicer profile with you. I uploaded my configuration to my personal blog, you can download it from the link below.
http://sinkhacks.com/prusaslicer-profile-for-the-mingda-rock-3-3d-printer/
This should include my settings for ‘.2mm Quality’, which is the baseline print settings I use for most prints. You can adjust it as needed to increase or decrease speed, resolution, etc. The Rock 3 is a large volume printer, so you may find it works better to print at a thicker layer resolution to make large parts faster.
Please let me know if the slicer settings work for you, and be aware that they may need some modification to work with your specific printer. I think they’re a good place to start, and it should help you to create the perfect profile for you application!
Thanks,
Andrew Sink