I’ve been having some continuing issues with getting the first layer to print consistently since I got the printer a couple of months ago. I also had some strange and inconsistent X/Y layer shifts in a print 2 weeks ago and couldn’t figure out what was going on. I did check and recheck all the bolts in the gantry and basically went over every bolt that I fitted during assembly with nothing being loose to a point where I would image it having an impact.
But last week I had a print fail spectacularly with the print not adhering to the bed and the printer ended up shutting down with a giant blob of PETG on the nozzle.
During disassembly I noticed that the entire Extruder Unit had some play. So I took it off the X/Y carrier that is mounted on the linear bearing and found that all 4 countersunk machine screws had backed out.
I ended up taking them out one by one, applied a medium strength thread locking compound and reassembled the carrier.
I’m currently waiting on some spares before I can reassemble the the extruder unit and start with a fresh calibration.
I’m pretty sure all my print issues are related to this carrier slowly loosening off and therefore throwing out the previous calibrations and Z height adjustments.
I am a bit perplexed to find that it’s only these 4 little machine screws that hold the entire assembly onto the linear bearing and that they were not assembled with a thread locking compound as a precaution to loosening off!
Hopefully this might help others having consistency issues with first layer etc. … worth checking those 4 screws!
