Frequently Asked Questions (V400,Super Racer, QQS Pro)

V400 FAQ

1.What type of motherboard is used in V400?

The V400 uses the MKS nano v2.1 motherboard with klipper firmware.


2.What is the type of driver used in the V400 and what is the range of current passing through it?

V400 using 2226 driver with 1.5-2A current.


3.What is the belt type and length and width of the V400?

V400 belt model GT2, width 10mm, single length 1458mm.


4.What are the nozzle types and available nozzle models for the V400?

The nozzle used in V400 is our own designed high melt nozzle, the profile size can be adapted to the crater nozzle, but the printing speed needs to be reduced when printing. v400 supports 0.2/0.3/0.5/0.6/0.8 caliber nozzle, but the configuration parameters in cura4.13 should be modified simultaneously.


5.What is the maximum temperature that the nozzle and hot bed of V400 can reach?

The nozzle can reach up to 300 degrees and the hot bed can reach up to 110 degrees.


6.How many ways are there to print on the V400? What are they?

There are 2 types of printing methods, namely U-disk printing and WEB-side printing


7.What kinds of print model file formats does the V400 support? What are they?

There are two formats, gcode format and ufp format (ufp format can show the model thumbnail).


8.What are the hot-side fan and motherboard fan models for the V400?

The hot-side cooling fan is 4010, the hot-side turbo fan is 4510, and the motherboard cooling fan is 6015.


9.Are the V400's heating rod and temperature sensor the same as the SR's?

The V400 heating rod and temperature sensor use a longer wire than the SR heating rod and temperature sensor, and the V400 heating rod has a power of 60W, which heats up faster and warms up more.


10.How to check the LOGO/LED light of V400 is not on?

Open the upper case of the machine, exchange the LOGO and LED jacks on the adapter board in the state of disconnection, turn on the machine and turn on the LOGO/LED lights to see if they can light up and down normally. To determine whether the LOGO / LED light problems or adapter board problems.


11.V400 machine can't connect to WiFi, what should I do?

1.After entering the wrong password, the network cannot be found. After reboot, you can delete and re-enter the password to connect.
2.It shows connected, but there is no ip address. The interface is: eth0 (network cable connection), you need to reboot the system to wlan0 (wireless connection), wait a while and the ip will appear.
3.There is an ip address, but the web side is inaccessible and shows an error. This indicates that the ip address has changed and you need to reboot to show the new ip.

    Note: The connection must be made under the same LAN, after the PAD is successfully connected to WIFI, it will always be the same IP as long as the WIFI is constantly on.


    12.What should I do if the nozzle hits the hot bed when the V400 is descending?

    1.It may be caused by incorrect leveling steps, please re-level it.
    2.It is possible that the configuration file is modified or damaged, please replace the original configuration file.


      13.How to adjust the nozzle scraping model when printing?

      1.Reduce the extrusion flow by ten percent
      2.Replace the Gyroid Infill Pattern
      3.Properly reduce the printing (idle) speed


        14.How to adjust the model does not stick to the hot bed?

        1.Adjust Z0. If Z0 is too high, the model will not stick to the hot bed, and if Z0 is too low, the model will warp. (If the first layer has excess extrusion need to reduce the starting layer flow)

        2.Properly increase the first layer printing temperature and hot bed temperature

        3.Add skirt to the model
        4.Apply solid glue to the platform


          15.How to adjust the V400 machine with uneven adjustment?

          1.First of all, make sure that the machine is installed firmly and without skew.
          2.Make sure the order of leveling is correct
          3.No impurities under the pei board
          4.No obvious resistance when sliding the slider, and keep the same tension of the three belts.


            16.What should I do if the klipper has stopped on the V400pad page?

            Whether this happens before or during printing, please open the web side of the machine on the computer page after connecting to WiFi to view the detailed error message. And send the error message to our after-sales service to solve it for you.

            Super Racer FAQ

            1.What motherboard does SR use?

            SR uses two different motherboards, SKR V1.3 and Robin Nano V3.0. If your printer is using Robin Nano V3.0,there will be a U disk interface, just like in the photo NO1.

            2.What stepper driver block does SR use?

            4 TMC2209

            3.What is the model of the SR belt? What is the length of one single belt?

            The model of the SR belt is: 2GT 10mm. The length of a single belt is 1250mm.

            4.What firmware does SR use? Where can I get the source files?

            SR uses an open source firmware based on Marlin 2.0.8, you can download the source file from FLSUN's official website.

            5.What type of nozzle does SR use?

            0.4mm volcano nozzle.

            6.What are the models of the three fans on the SR hot end?

            Two 4010 turbo fans and one 4010 cooling fan.

            7.What is the length of the SR ptfe tube?


            8.Why does the printer continue to print for about 1 minute when the filament run out?

            This is deliberately designed to prevent the filament from getting stuck in the filament detecting sensor, which may damage the filament detecting sensor when auto return the filament.

            9.What is the current of the extruder motor? How to modify the current of the extruder motor?

            The default extruder current of SR is 0.95A. Use Repetier to connect the printer, enter the command "M906 T0 E (value)", and then enter "M500" to save.For example, enter "M906 T0 E800" to modify the extruder current to 0.8A.

            10.What is the default steps of SR's extruder? How to modify the extruder steps?

            The default steps of SR extruder is 420. Use Repetier to connect the printer, enter the command "M92 E (value)", and then enter "M500" to save the steps of the extruder, for example enter the command "M92 E370" can modify the steps of the extruder to 370.

            11.What is the maximum printing speed of SR?

            When the printing speed exceeds 200mm/s, the printing quality will start to deteriorate, so we do not recommend setting the printing speed to exceed 200mm/s.

            12.What is the length of the SR parallel arm?

            315mm, the distance from the center to the center of the two fish eyeballs.

            13.What model of SR heating rod is?

            24V 40W.

            14.What model is the thermistor ?

            NTC 100K.

            15.What model is the SR power supply?

            24V 15A 360W.

            16.What model of SR motherboard cooling fan is?

            24V 6010 fan.



            QQ-S Pro FAQ

            1.Can QQ-S Pro install a second extruder?

            No, because there is no reserved installation interface for the second extruder on the motherboard.

            2.What are the specifications of the QQ-S Pro power supply?

            24V 15A 360W.

            3.What is the thermistor model of QQ-S Pro?

            NTC 100K.

            4.What is the model of the heating rod of QQ-S Pro?

            24V 40W

            5.What firmware does QQ-S Pro use?


            6.What is the length of each belt of QQ-S Pro and what is its model?

            The length of each belt of QQ-S Pro is 1486mm, and the model is 2GT 6mm.

            7.What kind of stepper drivers does QQ-S Pro use?

            4 A4988.

            8.Can QQ-S Pro be upgraded to other types of stepper drivers?

            Yes, QQ-S Pro can be upgraded to TMC 2208, TMC 2209, etc., but the firmware needs to be updated.

            9.What is the length of the parallel arm of QQ-S Pro?

            280mm,the distance between the center of the two fish eyeball heads.

            10.What are the models of the three fans on the QQ-S pro hot end?

            Two 4010 turbo fans, one 4020 cooling fan.

            11.What is the model and size of the QQ-S Pro heating block?

            E3D V6,and the size is 16*16*12mm.

            12.What is the overall size of the QQ-S Pro?


            13.Which filament does QQ-S Pro support?


            14.What is the maximum temperature of QQ-S Pro nozzle and hot bed?

            The temperature of the nozzle does not exceed 250°C, and the temperature of the hot bed does not exceed 90°C.

            15.What is the length of the QQ-S Pro PTFE tube?


            16.Can the extruder of QQ-S Pro be replaced with another type of extruder, such as BMG extruder, which parameters in the firmware need to be modified?

            The extruder of QQ-S Pro can be replaced with another type of extruder. You need to modify the pulse value of the extruder in the line ">EXT0_STEPS_PER_MM 367" to the pulse of the new extruder in the firmware configuration file.

            17.What is the model of the pneumatic connector?


            18.Can QQ-S Pro upload the latest Marlin? Does FLSUN have Marlin for QQ-S Pro?

            QQ-S Pro can upload Marlin, but flsun don’t have official Marlin firmware.



            1. What driver blocks does Q5 use?

            XYZ axis uses TMC2208, E uses 4988.

            2.Does Q5 support printing with WiFi ?

            Q5 does not support printing with WiFi because there is no WiFi module installed on the motherboard.

            3.What is the length of one Q5 belt?


            4.What model is the motherboard cooling fan of Q5?

            24V 4020.

            5.What is the length of the Q5 parallel arm?

            210mm, the distance between the centers of the two fisheye ball heads.

            6.Is it possible to install a second extruder on Q5?

            The Q5's motherboard has reserved ports for the second extruder, but we have not tested the installation of the second extruder on the Q5. If you are interested,you can give it a try.

            7.What model is the fan on the Q5 hot end? What is the supply voltage?

            The fans on the hot end of Q5 are 4010 turbo fan and 4010 cooling fan, they use 24V power supply.

            8.What is the model of the thermistor and heating rod of the Q5 nozzle?

            The thermistor model is NTC 100K, and the heating rod model is 24V 40W.

            9. What is the model of the Q5 power supply?

            24V 12A 240W.

            10. What the firmware does Q5 use?


            11.What is the length of the Q5 PTFE tube?


            12.What is the gear model on the Q5 XYZ axes motor?

            2GT 20 teeth.

            13.Why are the motor and synchronous wheel of Q5 fixed together?

            This can prevent the Q5 synchronous wheel from falling off the motor. If you need to replace the motor or the synchronous wheel, you need to replace all.

            14.Why does the print head fall down after the print is finished?

            You can download the latest firmware from our official website to solve this problem.