I’ve having trouble keeping it consistent all throughout the print. I get some layer lines really visible at random layer heights which changes its location when I print the same model several times, so it is not always at the same place.
What should I do to overcome this and have a clean consistent print?
nope. more likely stress build-up caused by sharp corner.
essentially model design problem.
Have you tried this with a normal or high flow hardened steel nozzle to rule out model design causing it?
I have tried with a normal 0.4 nozzle and it printed better but not perfect. I haven’t tried printing with 0.4 hardened steel though, I only tried the Tungsten 0.4 HF. I’m thinking maybe it’s the speed since HF prints faster than a normal nozzle but then I thought about it and it should all be inconsistent starting from bottom till top and not only on random layer heights. So I still haven’t figured it out.
The ones that came with the printer are hardened btw.
because what you’re seeing is caused by stress build up. HF only allowed it to be printed quicker and making the stress worse.
Again, even though the printer’s hardware allows faster printing speeds, it doesn’t really mean that you should..
But from the bottom till half way up it was fine with no issues, after that the layer lines are visible ( just like in the picture) and then went back to normal again at the top part of the print.
which is why it’s a stress build up. stress build up causes it to break, then the energy is gone and tries to build up again.
just like how earth quakes happen, stress build up, then erupt, then go quiet.
So basically just print it slower for better results yes?
yes,
also tungsten has a slightly more stickiness compared to hardened steel, so it’s going to be a little bit more stringy/draggy. but it won’t cause what you’ve seen here.
the design of the model itself needs some change tbh. the sharp corners are terrible for stress build up. too many walls would be causing enormous stress as well.
in short, Fillet on XY plane, Fillet on Z when facing upwards, Chamfer on Z when facing downwards.
I totally agree with you!
However, sometimes esthetics also play a part in the design.
Design for FDM is a skill on itself.
Usually these type of issues are caused by having a max volumetric flow rate that is set too high for the material and temperature. I would try slowing things down first.
I think it is the HF Nozzle using high Volumetric Flow Rate. Using a Normal 0.4 Nozzle always gave better results with the same model being printed. So yes indeed it is speed that is causing this.
