I’m not sure how to explain this but when printing the below, it comes out with the lines looking a bit clumpy at some location but I feel like it might be the design, that being said you can also see the lines don’t look uniform.
I’ve tried calibrating the temperature, pressure advance value, flow rate but to no avail. Always comes out similar. I have noticed it’s worth if I change the layer height and the lines go from bottom left to top right instead of bottom right to top left.
If you feel like you tuned all the parameters you mentioned well enough and the speed is reasonable, you should probably try the ironing for the best possible surface finish.
Thank you for your reply, I would say the only one I struggle with is flow rate, that didn’t really have one where it looked good. I had to use scratch method
I can’t even tell if this piece is over extruded or under extruded if I was to be honest. I think it’s over.
I’ve tried printing the top layer at 50ms but that didn’t help.
It’s weird to me how it’s worse in some parts than others though
I chose the 0.022 line and the -2 out of these pieces (original vs updated. Original looked like it had gaps) but how the box came out is atrocious and I have no idea why
Any help would be appreciated as I am either blind or not understanding something.
I understand, but I included it after as it seems to be only my metal blue filament and I had seen no layer reforms until I saw that scratch.
My black and galaxy purple seem to be fine. Although the top layer issues the same. Where the edges look different and the shorter the gap the worse it is.
It just seems if I try tune this it makes it worse… I am trying to dry the filament for 8 hours now to see if that helps. I also have a new plate and glue coming as well and last night I did a full cold pulls to see if that helps with the hardened steel 0.4 nozzle
I’ve not been very satisfied with the flow rate test in Orca Slicer honestly, as it’s very subjective and extremely difficult to tell with some filaments. I’d been using the method where you print a cube in vase mode and then measure the wall thickness with calipers, then divide the intended line width by it to determine flow rate.
Recently I discovered a new test that’s great for fine tuning (once you’ve done the vase mode cube mentioned before), and also if you don’t have calipers. Not to self-promote, but I made a remix of it to fix a couple issues too. I hope it helps you narrow down your issues. https://www.printables.com/model/985167-linkable-extrusion-test
Also, given the third image, looks like you might not be using monotonic infill for top/bottom surfaces. Might want to check and test that.
Monolithic is what you probably should be using, so I wouldn’t recommend changing that unless you want it for a specific thing. If you’re getting that pattern even with monolithic infill, then you might be right about it being overextrusion. Typically with overextrusion there will be raised ridges inbetween surface lines, because the filament has nowhere else to go. If the toolhead changes direction then the appearance can change because of that. You can also use that tendency it to get some neat patterning, like a sort of faceted look if you use concentric infill.
Thank you heaps! I will do the tests you suggested and see where it takes me I really do appreciate the help!
Would you recommend calibrating the flow dynamic or just let the printer sort that one out and just fine tuning the flow rate?
I know as per the images and. I looked under a microscope 0.022 was the best I could find using the tests but it produced noticeable bad results but not sure if that correlates with the flow rate being off as well (I’m somewhat new to this)
I believe the A1 has automatic flow dynamics which is for the “Pressure Advance” under filament settings, so you probably won’t need to fiddle with that. Flow rate is probably the only factor you’d need to play with. The defaults from the stock profiles are usually pretty decent but it can vary on a number of conditions.
There are instructions on the Bambu Lab wiki to manually enter calibration mode if you want to be sure about the pressure advance settings, though: Flow Dynamics Calibration | Bambu Lab Wiki
Thank and yeah it’s pressure advance but can confirm how orcaslicer and studio deals with that number is very different.
Did the same print from both with same values and they came out very different.
I’ll leave that on auto and calibrate flow rate, I dried the filament at 50 degrees for 8 hours overnight using a creality filament dryer so let’s see if that helps
I actually haven’t used Bambu Studio besides using it to set up my printer, though I find it odd that it would be using a different method for pressure advance, since both are based on Prusa Slicer and should be using the same method for that part.
It could be that something might not have been pulling the information for the profiles properly, not sure. I know some features are difficult to access if you aren’t logged into your Bambu Account, even if you’re using LAN-only mode. It’s weird.
Pressure advance, Flow are all subjective and hard to set with the standard calibration presets. Working with your metal/silk filaments makes it harder (silver is grrr fickle too). I’d be inclined to fine tune the filament to the model you’re printing moreso than to the squares and line methods in this case solely. Visually it looks like the PA is stopping short and the Flow is overextruding, try going down in PA 0.02 and Flow subtract .02 (eg if 0.97 go to 0.95). The drag lines at the hole section in the big rectangle print are notorious speed related I think, check your speed map in preview and slow it down as it’s probably too fast. Top layers about 80mm/s
I have slowed top layers but solid infill still had a high speed, is there a way to set the speed for particular layers? I’m assuming it would be done via gcode which I’m happy to add custom layers.
And for future I hate to ask this but whilst I can tell if something is over or under extruded, for a model to model print, how to you know if PA needs to be higher or lower?
The Pressure Advance slows the flow for hard stops at the end of a line, seen here by the edge few mm where the line thickness changes, shorter and less noticeable is better. Over-extrusion is shown by the raised sides as the filament is pushed out of the nozzle, similar to laying a line of silicone grouting when pushing too much it bulges around the sides too much, reducing that flow keeps it smoother, too little flow and it leaves gaps between the lines.
You can right click on the model in the prepare screen and select “Height Range Modifier”, then play with the object-specific print options. Just keep in mind to add more than one height range modifier you have to add it from the little +/- symbols at the bottom, rather than right clicking again. I had to see someone do it before I figured that one out… I think Bambu Studio should also have this feature? Not 100% certain though.
Thank you both so much! Am I safe to assume the following
If there’s a change in edge quality in the case it’s stopping too early like in the above prints it’s best to lower the PA value? I’m not sure what the opposite looks like but yeah.
Thank you both again and I’ll go through all this. First I’ll do the cube and print to get “standard” values then I’ll also calibrate to my specific print.
As mentioned before, pressure advance is most noticeable with corners or situations where the toolhead has to slow down and speed up again. So if you’re seeing lines separating at corners, you need to turn it down. On the other hand, if you’re seeing corners bulging, you need to turn it up. I find it’s a little tricky to tell which is which with infill, except in small areas (and then you have Small Area Flow Compensation, which is another can of worms entirely).
This is on both sides where the seam is but only seems to happen at the bottom. The seams not in connection of the baseplate are okay but not the greatest either.
I really do appreciate the help!
