I’ve recently gotten hold of a velleman k8200 and am having lots of issues.
I bought it built with upgrades: auto levelling, ramps 1.4 board etc.
It hasn’t printed from day 1. The printer homed itself and found its height. But the extruder was reading 700 degrees and wouldnt start a print, so i changed the thermistor. Little did i know , that was only the start.
None of the motors are now operating correctly. The extruder motor not work. Upon homing: The y motor simply goes back and forth a few steps with a huge deal of noise. The z axis goes a few mm in the air and stops. The x axis does not move but just makes a grinding noise.
Ive checked the micro switches, they seem fine. Ive checked all pins on the PCB etc seem fine. I;ve undid all the cable tidy and checked the solder joints - alot to check but they seem okay.
Ive read up on all the previous topics on this forum but as there is an issue with all 4 motors could there be a bigger problem on hand? Ive not checked voltage of motors with a multimeter but it did home itself and find its bed height before i changed the thermistor for the extruder.
If anyone could help that;d be amazing before i resolder and buy new replacement parts such as circuit board and micro switches.
There could be any number of problems that could cause what you are seeing. It is always trickier to diagnose if you don’t know for certain that the printer was actually working at some point.
If none of the motors will turn, you should start by verifying that your power supply is providing a steady 12V while the printer is running. Also, it can be helpful to connect the printer via USB to Repetier or Cura and look for any warning messages in the console output. Watch for thermistor errors, brownouts, or watchdog resets. This should also tell you what version of the Marlin firmware you are running.
Did the seller provide you with the source for the printer firmware? Usually this would have to be customized to match the printer it is running on, so that would be a good thing to have in hand. (I would refrain from re-flashing the Arduino at this point in your diagnosis.)
Since this is a RAMPS conversion, you are not using the stock Velleman controller. What kind of Arduino board do you have? An Arduino MEGA 2560 would be expected, but there are other variants that could be problematic. Also, can you tell if you have A4988 or DRV8825’s as your stepper drivers?
If you can post some close-up pictures of the printer and electronics, this may provide more clues.
Thank you so much for replying as i really am loosing faith.
I checked the power supply with my multimeter , its all good. I’m using repetier host to run the machine. Marlin firmware 1.1.6 . No major errors are standing out in the log.
The seller provided me with customized firmware which i uploaded via arduino. The arduino board is indeed a MEGA 2560. And i believe the stepper drivers are A4988’s. Please see we transfer link for image.
Also a video showing the lack of movement from all motors when i try to home each axis individually using repetier. I try to home the z axis first and the noise is awful. Would it be worth resoldering all wire connections?
The seller has been very supportive and i do believe the machine was working before i changed the thermistor. Just not sure what ive managed to wreck!
I’ve noticed a couple of things… The z axis is registering as home 200mm above the bed and won’t move lower when I press the x axis home button via repetier it just moves left. When I press the home button on the y axis it just jutters back and forth.
Aw lovely, thank you for that! I’ll go through all wires again. I I have really tried to check. If one motor / endstop wasn’t wired or mounted properly would that cause issues for all motors?
Brilliant. I had a look but then I fell asleep last night. But I’ll send through some photos of the ramps board too. I think I need new endstops. Honestly so much appreciate this forum and the support.
The type of micro switches used for the end stops are very reliable, usually rated for tens of millions of contacts. Unless they have all been physically damaged through some kind of abuse it is very unlikely that they need replacement. The wiring is much more likely to be the issue here.
On the Y axis, the symptoms are consistent with faulty wiring, a mis-aligned motor connector on the RAMPS board, a low control voltage setting on the stepper driver, or perhaps a loose set screw on the motor pulley. The fact that the motor continues to spin means it is not an endstop problem.
I would start by ensuring that all four motor connectors are aligned correctly on the RAMPS board, as it is very easy to be off-by-one when you connect these.
More photos will definitely help. You can attach pictures directly to your posts here, which is a better way to share them with other forum members.
when I press the x axis home button via repetier it just moves left. When I press the home button on the y axis it just jutters back and forth.