Anyone have thoughts on why I have visible lines at certain lighting angles on my first layer?
It’s bit hard to capture exactly with a camera, but you can see it in the middle of the picture. It’s only visible at certain angles.
I’m using a textured PEI plate. Bed levelling before each print. Tried cleaning plate, adjusting Z offset and first layer temperature to no avail.
Going to try playing around with flow ratios now, but figured someone must’ve had this issue before.
If you feel you’ve ruled out slicer settings have you examined mechanical ones?
Did you try change the orientation of the model by some random angle not aligned with 45 degree boundaries? If you did, has the angle moved. If the angle moved and stayed in the same plane as the bed, then I would examine your rods and make sure they are clean. There’s a wiki page for cleaning the carbon rods but only use IPA not any lubricant. If after that, I would look at lube on the pulleys. Then after that, take a look at belt tension.
For other ideas, check here if you haven’t already done so.
For lube on the pulleys, are you talking about the pulleys under the printer? Where do you put the lube, just on the axle?
I have a noise during z hops coming from the bottom, but it only happens during the first few layers. I posted here and somebody said they used oil on the pulleys.
I don’t know what settings you’ve changed in your slicer, try setting the Initial Layer Height to .3. It will give you a little more squish 
Did you ever find a solution for this? I have a brand new X1C that has the same issue. I’m really bummed about it.
Hi, I never found a solution. Monotonic Lines seems to be a bit better. I mostly notice this on prints with circles. I don’t get visible layer lines on say something that’s a flat square.
That’s crazy you never found a solution! Did you ever reach out to Bambu support? My printer is brand new, so I’ll definitely be sending it back if they can’t get this fixed. My entire reason for buying this was the perfect layers and stress free printing, I haven’t had either so far.
My print I need is just a big square too, and I have those terrible lines. I’ve spent literally 20 hours trying to remedy this with no success. Did you printer always do this? I have never had a good bottom layer, in the almost week I’ve owned it.
You should be able to post a picture now of the part that you have having issues with. This should help to diagnose the issue.
Those look like standard first layer lines from a flat plate. If you want to hide them further you should look at using a textured plate.
One tip I would suggest is to use “only one wall on bottom layer”. That will help to clean up the first layer.
Also have you calibrated your filament so the flow is correct?
I have the textured plate that came with the X1C, but I have to use the smooth carbon fiber for a part that I sell.
I would be very disappointed if the X1C can’t print on smooth surfaces well because my Ender 3 can do it perfectly on the exact same PEI sheet. There’s no lines at all like that.
I have done multiple flow calibrations, even buying multiple different kinds of PETG, drying it to the moon, then calibrating flow for them. To no avail or real change at all.
Pressure advance didn’t seem to change that exact issue either.
It seems like there’s wildly too much over extrusion but only around the walls. That’s what’s so weird. The flow rate change doesn’t touch that, just changes what’s in the middle, if that makes sense. But no setting I’ve found changes the amount of material extruded right before a wall.
