11mo ago

Biqu B1 - Not heating the hotend

A couple of days ago the hotend wouldn't heat up and i got a couple of errorcodes/warnings in the display. The bed heats up just fine, so i ordered a new hotend parts (heater, thermistor and a new aluminum block). Changed all of this, but still the same error. I can se that the thermistor works because it changes values in the display when touching the thermistor-end. Any good ideas why the heater doesn't heat?

39 comments

Do you have a multimeter? I'm not familiar with your printer, but is it possible to disconnect the heater wires from the motherboard and check the resistance between them?
- Yeah, i have ohm'ed the heater. It actually was the same resistance as the one i thought was dead... I don't remember the value (I'm at work right now)
  
  You don't want to read the resistance of the heater. You want to find the voltage being sent to the heat cartridge.
  When you're able to, disconnect your heat cart and stick your multimeter probes in the socket (or touch the top of the cable screws), and heat the nozzle. Should read 24v IIRC. Based on your answer to my other comment, my assumption is the number will not change when you turn on the heater, implying board or mosfet failure.
Welcome to Biqu B1 world. Where nothing makes sense and you'll never be able to get a nice print.
Mine came with the same issue and nothing solved it. It's literally a piece of trash in my room. Saving for a Bambu. btw I have a Elegoo for years and it's perfecr
- out of curiosity, why would you not have gone with an Ender 3 over this non-brand thing? Or if you have Bambu money, that or another quality brand? It sounds like a recipe for pain and it's not cheaper than the super well (community) supported Enders.
  
  I'm a totally noob in the 3D printing scene. My brother has a Biqu B1 and I've printed some small things on his printer. Found a used Biqu B1 for sale for about $80. Yeah, not good research from my side... But, I've printed a well printed fucktopus before it died...
  
  Because I'm dumb. I don't have bambu money and a couple of years ago I didn't even knew about it. I read somewhere that biqu b1 was better and had less problems than the Ender and was noob enough to fall for it. I'm used to resin printer so I didn't knew enough about fdm and just went with biqu. Horrible decision
- That sucks. I have no clue about 3D printers and did no research before buying this one used. Worked OK for about 6 days.... Well 80 bucks...
  
  You can get a new board for <$50 (you don't need the same board that's in the printer), spend an hour or two learning how to move the cables from the old to the new, and still have a pretty good deal
Make sure the wires to the hot end actually trace back into the main board. And the mosfet is fine.
- It's just USB-C cable up to the hotend. Not sure how to check the mosfet..
I can se that the thermistor works because it changes values in the display when touching the thermistor-end.
Good information. You can probably remove thermistor from possible cause, but to be sure, you can tape the thermistor to your heat bed, and heat to a high temp, make sure that the "nozzle" temp is close to the bed temp
What is the behavior when you hear the nozzle? Does it immediately give error, or does it take some time? If it takes some time, is the temp changing on the nozzle at all, or it stays the same until error?
- When starting the preheat both the bed and the nozzle temperature starts at about 25c. There is no heating at all. The printer takes about 10-15 sec to conclude with the error message.

39 comments