hi, i just recieved my obxidian nozzle and im really having a lot of trouble working through the calibrations for polymaker petg polylite pro. I have a good tuned profile for the regular but i cant seem to get the advantages of the obxidian nozzle.im having trouble figuring out what to change.
Which test am i supposed to do and does anybody have a baseline i could start from?
thanks
I think for the first tests, I used one of my profiles for the stock hotend, increased max flow to 35³mm/s and reduced nozzle temperatures by 10°C. Zhat already worked really well with matte PLA and PETG HF. I repeated some calibrations in Orca Slicer, but the differences weren’t big.
Which problems do you see with which filament?
Bambu has now profiles for the E3D obxidian hotends.
But even without them it is not that hard to tune into the right numbers and settings.
Start with the default profile you have and that worked well for the normal hotend.
Calibrate the nozzle temp, flow ratio and k-factor.
Run a max flow rate test and use the result to set your max flow rate.
That gives you a working base profile.
Some filaments can be tricky and making full use of the theoretical speed improvements is not always possible.
Best to start with a good quality profile to then work on the speeds and things like retraction values and acceleration settings.
I prefer to start with a moderate max flow rate of around 25 to tune the setting for best print results.
After that I increase the max flow rate to test result values and won’t really have to touch the speed settings much at all.
Already prints much faster with the default speed values.
If you are after the best possible speed AND quality use some simple test models like pointy stars and thin single walls.
You can get the max print speed that worked from the preview of the max flow rate test.
But that is an ideal number that won’t work on many models.
The key is to find a good balance between max speed and lower acceleration values.
If the printer get very noisy and rattles it means the print result won’t be ideal and the wear and tear on the machine is high.
Tuning for speed…
The smooth area discontinuity feature can be a real helper here!
The speeds from the default profiles should not cause too many issues if you ramp the max flow rate to 40 or even a bit higher.
But when can you or do you use these high volumes ? 
First culprit is the combined infill - this sucks up the most filament.
It is also a great time saver when printing with low layer heights, so it makes sense to tune the infill speeds first using combined infill at a layer height of 0.1 or 0.8mm.
Pay attention to detail as you have to use an infill area large enough to allow the print head to get to the max speed you play with!
Without this attention and just using small test cubes you might end up with weak or failing infills.
Perimeters/walls matter and the highest speeds are reached with the inner walls.
You want these to come out acceptable enough for your needs.
Go too high on the speeds and especially models with finer details might suffer as the outer wall might not be printed as good as possible.
For the outer wall speeds don’t be shy to make a compromise.
It is better to go a bit lower that what the max suggests as there is always a model that will throw you off later.
Check the wall closely and if the last speed increase made it look worse go two steps back.
Top layers and infill…
You can go surprisingly fast here but not always does it make sense.
Like tiny holes with too high inner wall speeds create loud noises and vibrations the same can happen with top layers and their infills if tiny.
That is where the acceleration setting can come for the rescue.
If only those fine details make your printer sound as if it is falling apart try to lower the acceleration values a bit.
And yes, I still prefer to manually calibrate new filaments to get the best possible result.
Don’t forget to consider layer height and line width as parameters. They are very effective for making use of the increased flow and taking less time.
E.g. for bigger parts that need to be sturdy, I would recommend to change inner wall line width to 0.6 or even a bit more. That way you can reduce the number walls needed for the same wall thickness.
To prevent degradation of outer walls, set wall print order to outer/inner/outer.
But another thing im trying to understand is for example once a filament is tuned, are you supposed to turn off auto calibration at the beginning of the print? and if yes, for what setting that you input the value should compensate for removing the dynamic flow calibration?
what im asking is what value does the flow calibration at the beginning calibrate for? Which setting?
Also, i been comparing the presets of hf vs regular nozzle
Thanks
ploymaker PETG im having some trouble. polylite PLA pro is a bit better but i feel like im not able to take advantage of the hf nozzle
What is it that you expect to gain ?
I calibrate every new roll of filament from a new batch or supplier.
And when I change to a new but established roll I still check the calibration matches.
Go ahead and do some basic math to calculate the area of 0.4mm hole.
Then check the volume for this area if the cylinder is 0.2mm high.
You can use your line width if you prefer…
Point is that with such small volumes a little bit off on the flow ratio can cause a lot of trouble.
If you want to see how good the hotend is than do a few test prints with the Bambu profiles and then just select the normal nozzle in the settings and do a full manual calibration of filament and print settings - the later either for speed or for quality or both.
You will find that what you established will be quite different to the Bambu defaults for the E3D.
I can max out the 500m/s limit of the machine using PLA if I have to…
But I am more after the quality the E3D provides and usually am not in enough of a hurry to rattle the printer apart just to get a bit faster print.
