Rough print finish and dimensional inaccuracy
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@TRATOON Is the 800 steps/mm full steps or is it based on 16:1 ustepping? or some other ustepping ratio?
A Z axis with 800 full steps/mm moves1.25 um per full step of the Z axis motor(s). Your print layer thickness should be any whole number multiple of 1.25 um. A 200 um layer will be 160 full steps. A 300 um layer will be 240 full steps. A 100 um layer 80 steps, etc.
If 800 steps/mm is based on 16:1 ustepping, then you actually have 50 full steps/mm or 20 um. In that case you can still print in 200 or 300 um layers, but don't print in 150 um layers because 150/20 = 7.5 : not a whole number.
Pressure advance is one of the various ways of tuning the extrusion to fix certain types of problems, especially blobbing in corners. See: https://docs.duet3d.com/en/User_manual/Tuning/Pressure_advance
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@mrehorstdmd No it is just 800m/s no upstepping. So you are saying I set it back to 800m/s and I will be fine printing at 0.2 mm and 0.35mm as both of those are divisible evenly by 1.25um?
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@TRATOON Your existing configuration is using 16 microsteps on Z see:
M350 X16 Y16 Z16 E16 I1so the 800 (or 798.929 as you currently have it) steps/mm will include that, which as above means 50 full steps/mm.
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@TRATOON I'd say this was classic Z-banding, where the Z axis isn't moving the correct amount, due to not using a multiple of whole steps each layer. As @mrehorstdmd has pointed out, your Z steps per mm are Z798.929. Change it to Z800, and use a multiple of 0.02mm for your layer height. I'd be amazed if you can actually measure the 0.125% difference in height!
Personally I'd use whole numbers for steps per mm, and if you need to scale the print afterwards, use M579 to scale axes (but not Z). Though I think once it is printing nicely in Z, you'll find the X, Y and Z dimensions are more accurate. If Z scaling is noticeable, you will be better off scaling in the slicer, so you maintain the Z layer height.
Also, your Z axis is using two drivers (
M584 X0.0 Y0.1 Z0.2:0.3 E121.0), but you don't have an M569 for the second driver. Add this to config.g (check S parameter makes the motor go the correct direction):M569 P0.3 S1 ; physical drive 0.3 goes forwardsIan
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@TRATOON Since you actually have 20 um/full step (50 full steps/mm), you should not print at 350 um layer thickness because it is not a whole number multiple of 20 um. Try 340 um or 360 um...
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@TRATOON You mentioned 350 um layer thickness (and previously 300 um)... In my experience, best print quality is achieved when line width equals nozzle diameter and layer thickness is no more than 1/2 of the line width. You can get away with line width a little wider than the nozzle diameter, but never narrower. So you could print at 500-600 um line width, and use layer thickness up to 250-300 um with a 0.4 mm nozzle. I wouldn't try to print wider than about 0.6 mm, so I wouldn't try to use layer thickness grater than 300 um.
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@mrehorstdmd I just finish printing my part with a .2mm layer and .3mm for initial layer with a .4 nozzle and line width of .4. I also added the motor line as @gloomyandy pointed out and reset my steps for motors to 80,80,800. Now, my print quality is better, but there are still some ridges however I noticed they only occur on the left side of the x axis (facing printer from front). The corner thing is still mildly present and then there are these lines on the surface of print (circled). The face of the part in the image you can see was printed in the back of the printer. I calibrated only E-Steps, should I calibrate flow as well?
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@TRATOON The Hemera is a dual drive gear extruder- this might be of some help: https://www.youtube.com/watch?v=32dTLRNIYmw
Have you checked to make sure everything is bolted together solidly, and that belts are "tight but not too tight"? Look for any mechanical wobble, etc., and fix it.
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@mrehorstdmd How tight should the belts be I'm using exoslide so I will reach out to him to see if any of the exoslide parts can cause this problem, also what are some areas where wobble might be common?
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@TRATOON For smooth motion on the X and Y with our ExoSlide Ender 5 Plus kits (or any other setup) the goal is low friction on the slides, and decent belt tension. The ExoSlide carriages should all slide smoothly on the extrusions with the belts removed. The bearing treads should also all contact the extrusions (to prevent wobble), but not be overly preloaded as that increases friction. We have a guide install video on our website under Guides > ExoSlide Adjustment.
Are you using a metal or printed mount for the Hemera? If using the metal mount, ensure the washers under the M3 bolt heads are used. It should be snugly mounted to the carriage face.
Regarding the Z, the Ender 5 Plus can be over constrained at the ends of the travel where the Z rods don't flex. If you removed the Z lead screws, can the bed travel smoothly up and down by hand (especially near the top)?
Regarding belts, as mentioned above, the XY belts should be tight but not crazy tight that brackets are bending. On the X, I tension the X idler bracket with one hand and secure the bolts with the other. On the Y, I use a small screwdriver or allen key to pry the front idler brackets forward and tighten the bolts with the other hand. One last note on the Y belts, ensure they are not twisted when then return in the extrusion.
If all those steps check out, one troubleshooting step I would take is to reduce variables in the system, and temporarily install the factory hotend/bowen/extruder on to see if that cures it.
