QIDI X-Max (2019) Known Issues and How to Fix Them

The QIDI X-Max is a 2019 enclosed FDM printer with a 300×250×300 mm build volume, a 300 °C hotend, a 120 °C bed and two swappable extruders. It's discontinued, but plenty of them are still running. This guide covers the problems that are specific to this machine, with step-by-step fixes — not the generic advice that applies to any printer.

Don't mix it up: this is the original X-Max on a Cartesian frame with dual Z lead screws, not the fast CoreXY QIDI X-Max 3. They have different electronics and different quirks.

Heat Creep and Clogs with PLA and Special Filaments

The classic symptom: the factory test file prints perfectly, but your own models jam after a few layers. You open the extruder and the gears are packed with plastic, as if the filament melted before reaching the heat block. It's not under-heating — it's over-heating: inside the enclosure an ABS print pushes chamber temps to 59 °C, the hotend heat sink can't keep up, and you get heat creep — filament softening too early.

Silk, clear and glow-in-the-dark PLA suffer the most — they melt at a lower temperature, so they clog more often. X-Plus and X-Max owners on forums all reach the same conclusion: when printing PLA and TPU, remove the top acrylic cover and open the door so the chamber doesn't turn into an oven. There's even a factory sticker that says so.

The X-Max ships with two extruders: a standard PTFE-lined one (good to about 250 °C) and an all-metal high-temp one (up to 300 °C). The standard one is more prone to heat creep, so for nylon, polycarbonate and carbon fiber you're better off swapping to the all-metal extruder — it has no PTFE liner to degrade at high temps.

1. Print PLA and TPU with the door open and the top cover removed
2. Clean the nozzle and extruder gears, and do a cold pull
3. For silk and clear filaments, drop the temperature 5–10 °C and reduce retraction
4. Make sure the heat sink fan is spinning and free of dust
5. For nylon, PC and carbon fiber, fit the all-metal high-temp extruder and a hardened nozzle

Extruder Flat Cable and Adapter Board Failure

The print stops mid-job, the hotend stops heating or shows a jumping temperature, and sometimes the printer just freezes. Often it's fine at the start and throws an error a few minutes in. The usual culprit is the extruder flat cable: it flexes constantly with the head and eventually wears through. QIDI itself states that most of these temperature errors are caused by the print head cable or the adapter board on the carriage.

1. Power off and inspect the flat cable for kinks and wear near the carriage
2. Wiggle the cable connectors on the adapter board and mainboard — a loose or corroded contact breaks the signal
3. If the printer freezes, re-slice the file and power-cycle first — a corrupt G-code also stalls the print
4. If that doesn't help, replace the extruder flat cable
5. If the error returns, replace the extruder adapter board on the carriage

Hotend Not Reading Temperature: Thermocouple and MAX6675

Unlike most printers, the X-Max measures hotend temperature with a thermocouple, not a thermistor. Its signal is amplified by a dedicated MAX6675 chip on the board. Failure symptoms: wrong temperature on screen, an "ADC out of range" error, a MINTEMP message, or a heating failure. Sometimes the reading sticks at room temperature or jumps around.

The tricky part: a frayed thermocouple wire can short and burn out the MAX6675 amplifier itself. Then replacing only the thermocouple won't help — owners on forums swapped the thermocouple, the breakout board and the cable with no luck until they got to the chip. So work through the diagnosis from simplest to hardest.

1. Let everything cool and inspect the thermocouple wire for wear near the hotend
2. Check that the thermocouple sits properly in the heat block and its connector is seated
3. Replace the thermocouple with the OEM part — this fixes most cases
4. If the error persists, it's the MAX6675 amplifier chip on the board; easiest to swap the whole hotend or get a tech with a soldering iron

Z-Wobble and Ghosting from a Heavy Print Head

Repeating waves at even intervals show up on vertical walls — that's Z-wobble. The X-Max has two independent Z lead screws, and screw runout is transmitted to the bed through the top bearing. On top of that, the swappable extruders are heavy: at speed they cause noticeable ghosting around sharp corners. Reviewers noted back in the X-Max review that the massive head forces you to live with some ringing.

1. Lower speed and acceleration — the heavy head needs gentler settings, which removes a lot of the ghosting
2. Check and lubricate the lead screws, and make sure both Z screws are at the same height
3. Community fix: remove the top bearing on the lead screw and rely on the stock coupler, so the screw no longer transmits runout to the frame
4. Print and install an Oldham coupler — there's a free model on Printables

Bed Leveling Drifts and Springs Sag

Over time the first layer starts to drift: too squished in one corner, lifting in another. The X-Max uses assisted manual leveling — a probe guides you while you turn the corner screws. The soft stock springs gradually sag, and the two independent Z screws can drift apart in height, so the setting holds worse and worse. For the first layer itself, see our dedicated guide.

1. Heat the bed and nozzle to printing temperature and run assisted leveling from the menu
2. Check the gap with a feeler sheet at all corners and the center
3. Make sure both lead screws are at the same height before calibrating
4. Swap the stock springs for stiff ones (a 9N leveling nut and spring set) — they hold the setting much longer

Magnetic Bed Coating Wear and Lost Adhesion

The double-sided magnetic bed is handy — you pop prints off by flexing the sheet. But the coating wears out: parts stick less, the surface polishes to a shine, and the sticker tears at the edges. More often than not it's not wear that kills adhesion but bad cleaning — skin oils and, especially, acetone, which eats the texture.

1. Wash the surface with warm water and oil-free soap, then dry it fully
2. Never use acetone on the textured surface — it damages it
3. Refresh polished PEI with fine sandpaper or steel wool, then wash off the dust
4. Replace a torn sticker; for high temps fit a steel HF plate or a PC plate

The Outdated QIDI Print Slicer

QIDI Print is a fork of an old Cura release (4.x). It looks dated, has few settings, and lacks acceleration and jerk control. Worse, the closed firmware is partly incompatible even with it. The good news: the X-Max works great with modern slicers once you build a profile for it.

1. Move to a current OrcaSlicer, PrusaSlicer or fresh Cura and build an X-Max profile (300×250×300, 0.4 nozzle, moderate speeds for the heavy head)
2. Print from a USB stick — that way you don't depend on the slicer connection at all
3. For network printing from a third-party slicer, add port :10088 to the printer's IP
4. Don't rely on the QidiPrint plugin for Cura — it's been abandoned for about four years and errors out on recent versions

Flaky Wi-Fi and Dropped Connections

The X-Max's Wi-Fi is weak: it won't connect, drops the link, and the slicer keeps losing sight of it. Crowded 2.4 GHz networks make it worse. Luckily the machine has a wired LAN port, and printing from a USB stick doesn't depend on the network at all.

1. For reliability, connect the printer over a LAN cable instead of Wi-Fi
2. For third-party slicers, add port :10088 to the IP
3. As a fallback, print from a USB stick
4. Keep the printer close to the router and move it to a free 2.4 GHz channel

Closed Firmware and the Tricky Klipper Path

The X-Max firmware is closed and proprietary, running on a Chitu V4.6 board with an STM32F407 processor. As a result M118 doesn't work, there's no proper acceleration or jerk control, and features can't be updated. Installing Klipper sounds tempting, but you can't just flash it — public Klipper doesn't match the board. Sven Eckelmann wrote a detailed walkthrough of the process.

1. Assess the risk honestly: without soldering and firmware experience, don't start
2. Klipper is flashed with an ST-Link v2 programmer and STM32CubeProgrammer over SWD, with a mandatory backup of the stock firmware
3. After the switch the stock Chitu screen won't work — you'll need a Raspberry Pi and a separate display (e.g. a Waveshare 5")
4. If you don't truly need Klipper, stay on stock and solve your needs with a modern third-party slicer

Bulky Print Head and Exposed USB Port

To fit two swappable extruders, QIDI built a large print head assembly. It blocks your view of the print start, especially small parts, and gets in the way when you fish dropped objects out of the chamber. And the USB port sits on the lower front panel — easy to catch with your foot and damage. These aren't failures, just quirks to get used to.

1. Watch the first layer from the side and through the door, not from the top
2. Retrieve dropped parts after the head parks, not while it's moving
3. Protect the USB port: don't kick it, and use a USB extension if you plug in often
4. Account for the heavy head in your settings — gentler acceleration, lower speed on small parts

What the Error Messages Mean

The original X-Max has no alphanumeric error codes like Bambu Lab or QIDI's newer Q-series — the screen shows plain text messages. Here's how to read the most common ones and where to start.

Common 3D Printing Problems

Beyond the X-Max's unique quirks, you may run into problems common to any FDM printer. We've covered each in a dedicated guide:

• Nozzle clogging: full guide — causes, cold pull, cleaning
• First layer setup — Z-offset, adhesion, bed temperature
• Fixing warping — especially relevant for ABS
• Getting rid of stringing — retraction, temperature, drying
• Choosing and drying filament — wet plastic means clogs and stringing
• Ventilation and ABS fumes — important for an enclosed chamber
• Regular printer maintenance — so problems don't come back

Also worth reading: thinking about an upgrade — compare it with the newer QIDI X-Max 3 and its known issues, and if you're choosing between brands, see QIDI vs Bambu Lab.

Frequently Asked Questions