Continuous vertical lines on shell
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@nophead said in Continuous vertical lines on shell:
Is the pitch of the lines related to the belt tooth pitch?
Do you have any toothed belts running tooth side inwards over smooth pulleys?
I'm not quite sure how I would relate the line pitch to the belt pitch, any tips?
I do have a smooth idler facing the teeth on the Y-axis (which is also the axis that shows the issue more), I have the correct toothed idler around, attaching it just ended up being a pain so I left the stock (smooth) one in there.
I wonder though why this wasn't an issue from the beginning when I got the printer, possibly softer teeth than my Gates belt now? Ie the teeth just being depressed enough that it didn't really matter?
@dc42 said in Continuous vertical lines on shell:
@nophead said in Continuous vertical lines on shell:
If the striations are vertically aligned doesn't that rule out the extruder? I mean wouldn't it be a remarkable coincidence to have a perimeter that was an exact multiple of the extruder microsteps or tooth pitch?
Isn't it more likely axis speed modulations?
That's a good point. But if it's axis speed modulations, why does it change with layer height?
Hm maybe something to do with some extruder jerk or whatever value leading to different speeds at higher flowrates? Pressure advance?
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@diamondback said in Continuous vertical lines on shell:
I'm not quite sure how I would relate the line pitch to the belt pitch, any tips?
The belt pitch is likely 2mm. Is the distance between ridges also 2mm?
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@phaedrux said in Continuous vertical lines on shell:
@diamondback said in Continuous vertical lines on shell:
I'm not quite sure how I would relate the line pitch to the belt pitch, any tips?
The belt pitch is likely 2mm. Is the distance between ridges also 2mm?
The pitch seems to be something like 1.2mm (averaged over 7 peaks), hard to measure...
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I have measured mine and it was the same distance which You measured.
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@diamondback How many teeth on your pulleys?
If it isn't related to belt pitch then perhaps motor steps.
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@nophead said in Continuous vertical lines on shell:
@diamondback How many teeth on your pulleys?
If it isn't related to belt pitch then perhaps motor steps.
Both idler and pulley have 20 teeth on both axis.
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I have found the solution. You need to use teeth idlers instead of flat.
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@petrzmax said in Continuous vertical lines on shell:
I have found the solution. You need to use teeth idlers instead of flat.
Glad this worked for you
I'm in the middle of switching my idler to a toothed one as well, need to fabricate a custom screw first though, the idler is 5mm ID and the attachment is an M4 screw.... -
@diamondback I'm in fabricating phase aswell. The research I made told me that it should make ghosting less visible and get rid of this lines. Unfortunatelly i have not standard derlin idlers so I will need to print idlers. I hope they will be good quality. If they will not I will need to buy metal ones and redesigns some parts which I'm trying to avoid.
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@petrzmax This is how I first solved the problem: http://hydraraptor.blogspot.com/2011/06/half-belt-hack.html
For Mendel90 I just put a half twist in the return path of the belt because toothed idlers were not commonly available then.
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@nophead Thanks for the idea! I will try to give it a go, but I'm on CoreXY and ther might be a problem with twisting them. Never tried twisting them before
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@petrzmax Not sure it will work on core XY because the you can only put the twist in a stretch that doesn't contract to a short length, ideally constant length like above. I am working on an H-bot design and concluded I needed toothed idlers.
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Ok, got my idler changed now to the correct toothed one, but that didn't do much I'm afraid...
So back to extrusion related issue I guess. Anything I can try to adjust software wise before taking the Titan apart?Maybe someone can take a look at my config.g in the first post and see if there are any obvious issues
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If you print something with different outside dimensions do you ever get diagonal lines? I can't see how the extruder can create vertically aligned striations.
How many shells are you using. With single wall I sometimes see striations from the infill pattern through the wall.
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I use F608 bearings for idlers in my corexy printer with the toothed side of the belts riding on them. I get no such vertical ridges. Maybe you need to use larger diameter pulleys. F608s are 22 mm in diameter.
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@nophead said in Continuous vertical lines on shell:
If you print something with different outside dimensions do you ever get diagonal lines? I can't see how the extruder can create vertically aligned striations.
How many shells are you using. With single wall I sometimes see striations from the infill pattern through the wall.
I'm usually using 3 shells at .4mm, the lines are always perfectly vertical, sometimes there are diagonal lines on top of that, not sure where those comes from.
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@diamondback What happens on diagonal sides?
If it was somehow a flow rate variability synchronised between layers I would expect it to look exactly the same.
If it is due to variations in linear speed due to motors or belts I would expect the pitch to increase on a diagonal because each axis is moving slower for the same linear speed.
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@nophead said in Continuous vertical lines on shell:
@diamondback What happens on diagonal sides?
If it was somehow a flow rate variability synchronised between layers I would expect it to look exactly the same.
If it is due to variations in linear speed due to motors or belts I would expect the pitch to increase on a diagonal because each axis is moving slower for the same linear speed.
Just tested, straight vs diagonal do differ quite a lot. I'm currently test printing something without micro step interpolation.
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@diamondback Let us know about the results!
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Nope, no changes... Tried different micro stepping for both axis and the extruder, with and without interpolation, nothing...
Is it possible that my motors are just crap? (or not well selected for the task at hand)
I'm running these steppers on both axis and the E3D Pancake on the Titan.
(Used to be one of the ACT ones as well but I significantly reduced the X carriage weight a while ago and switched to that small stepper then)
