Models become brittle and fray
A few weeks ago, out of nowhere, my models started to lose their complete layer to layer adhesion. The models look great when they are printed (see first picture). As soon as you press them together a little (not hard, minimum force between two fingers) the individual layers separate from each other (see second picture):
I have already tried a few things:
1. adjusting the printing parameters for better adhesion (temperature high, extrusion rate high, etc.). Hardly any improvement
2. Took another filament roll (several different ones, including one previously in its original packaging (Prusament)). Did not help.
3. took the complete hotend apart and cleaned it. No change.
4. installed a new hotend (original) including heating cartridge and thermistor. Since then I've had an extreme stringing problem (I'll have to do it again), but regardless of that, the models are no better.
I'm slowly running out of ideas. Help would be very welcome. Many thanks in advance.
Try slowing the print - use the LCD menu - use 50% first to be certain.
Sometimes speed mods and tailored presets swap too much strength and precision for speed. - so, if it helps you may need to reduce print-move speeds.
- I would use cubic fill for that sort of part.
Cheerio,
RE: Models become brittle and fray
I don't have any of these modifications. My printer is a normal Mk3S+. I also don't print with any strange settings. I use the default settings that are pre-set in Prusa Slicer and have always used them. I have also tried it with 80%. Unfortunately, that didn't help either
RE: Models become brittle and fray
I expect the nozzle is (partially) obstructed. If you have a caliper you can measure the diameter of the extruded filament. When using a 0.4 mm nozzle this has to be about 0.45 mm. If this is ok then perhaps the transportation of the filament is somewhat hindered.
Good luck!
RE:
Strange issue. To check if you have underextrusion because of a partial nozzle clog or any other reason, weight the finished print and compare the value obtained to the weight of the print reported in Prusa Slicer ( a variation of +- 5% would be acceptable ).
BTW. The filament on these pictures isn't, by any chance, Prusament PLA blend lime ?. If it is, that explains the poor interlayer adhesion, at least for this specific print. Prusament PLA blend filaments are awful in this aspect.
If the hotend has been replaced then partial clogging is unlikely.
The walls look thin,; try adding another perimeter or two, functional parts generally need more than trinkets.
Cheerio,