Stringy first layer raft and hard to detach model form raft

Hi

After 3 years or so of great usage, I have been encountering multiple problems with my M200 as of late.

At first, the extruder started skipping during raft printing. I replaced the extruder bearing as it was broken, I also cleaned out the entire extruder and motor assembly and replaced the nozzle with a new one. The problem is still present however and the first raft layer prints very fine lines and the skipping stops once the model begins printing.

Lately, the problems have gotten worse with the first layer of the raft being very stringy (see attached image) with bad adhesion to the build plate irrespective of the size of the part. I removed the build plate and did maintenance as per the guidelines on the zortrax site. That didnt help anything and now its also become very difficult to remove the parts from the raft.

I’m happy to replace parts if it will resolve the problem but I don’t know which ones need replacing. I was thinking the problem may be with the build plate since its quite old and/or perhaps the thermocouple isn’t heating up to the correct temp anymore. Not sure whether the ribbon cable could also possibly be at fault.

Any help would be much appreciated!

Hi,

If the extruder is skipping while printing first layers of the model or the raft only - most probably it indicates that the nozzle is too close to the platform. Increasing the platform-raft gap should help.

Can you provide calibration results after the platform maintenance? Despite the fact the nozzle is new - the hotend might be clogged with material residues. When was the last time you replaced the hotend? The heater&thermocuple also might be malfunctioning - make sure all the cables are firmly plugged into the PCB and that screws securing the component in the hotend are tight.

A lifespan of paricular components can be found in iur our maintenance guide.

Best regards,
Karolina