Final Layers Uneven in Corners  

Re: Final Layers Uneven in Corners

the lifting is definitely causing that....should not need a brim but if it helps then hotter and slower for the first layer are your friends.

Re: Final Layers Uneven in Corners

the lifting is definitely causing that....should not need a brim but if it helps then hotter and slower for the first layer are your friends.

Thanks for the advice. As it stands the slicer seems to do that for the first layer already, would it help to do it for additional layers?

Re: Final Layers Uneven in Corners

How does the first layer of the print look? I would try to stop the print after the first layer (or print things like this: https://www.thingiverse.com/thing:2886087 - There's a lot to choose from), and take a look. I had a lot of issues getting the first layer printing consistently across the entire bed. If it's not then the print will curl or sometimes the whole model comes undone.

You can pretty easily tell if this is the case by printing a first layer around the same area you're having lifting and see if there is a change in pattern for the first layer. It might be too squished or not squished enough compared to the other areas in which case you might have to tweak some of the bed leveling settings available or maybe re-run the calibration.

The other option is to move the print somewhere else where it doesn't hit that spot. I found on my MK3 (now MK3S) that I had issues on the upper left and then most of the right side of the bed. I think this has to do with pinda noise. Also found it more consistent to always let the pinda heat to 35C or 40C before doing the calibration otherwise you keep on getting different results.

Also found that my bed plate was hard to get really clean. A simple ISA wipe didn't always work. I had to wash it with soap and then ISA to get it to really work especially the first time.

Re: Final Layers Uneven in Corners

How does the first layer of the print look? I would try to stop the print after the first layer (or print things like this: https://www.thingiverse.com/thing:2886087 - There's a lot to choose from), and take a look. I had a lot of issues getting the first layer printing consistently across the entire bed. If it's not then the print will curl or sometimes the whole model comes undone.

You can pretty easily tell if this is the case by printing a first layer around the same area you're having lifting and see if there is a change in pattern for the first layer. It might be too squished or not squished enough compared to the other areas in which case you might have to tweak some of the bed leveling settings available or maybe re-run the calibration.

The other option is to move the print somewhere else where it doesn't hit that spot. I found on my MK3 (now MK3S) that I had issues on the upper left and then most of the right side of the bed. I think this has to do with pinda noise. Also found it more consistent to always let the pinda heat to 35C or 40C before doing the calibration otherwise you keep on getting different results.

Also found that my bed plate was hard to get really clean. A simple ISA wipe didn't always work. I had to wash it with soap and then ISA to get it to really work especially the first time.

Thanks for the reply.

That is the odd thing, the first layer is (to my eye) perfect. However I think it may be that part of the bed, it seems to happen in the upper left quadrant more than other places.... Any tips on that, I preheat before leveling so I think that marks off your first suggestion

Right now I have a print going at 90% speed with a brim, so we shall see.

Re: Final Layers Uneven in Corners

Hmm... if the first layer seems even then I'm not sure. A few thoughts:

* Maybe your Z adjustment is overall too high or too low. If you have some sort of adhesion problem I found you get the curling problem at the edges (until the entire thing comes lose). Since you only have it on one corner this might not be it...
* The upper left is where the heating element is. I wonder if the bed there is slightly hotter. Maybe try reducing the bed temp a little (e.g. from 60C to 50C). But it seems to have happened to you elsewhere too...
* How much is your infill on the model? Curling happens more if you have a lot of solid layers on top of each other. You could try to reduce your infill and or bottom layers. Could also try to print at a cooler temp. on your "Other Layers".

Re: Final Layers Uneven in Corners

I was at 15% infill, for them all.

I will say I just pulled my most recent batch off. Going at 90% speed, with a brim did a treat. They came out fine.

So a few theories of mine, I did worry the first two like a new parent, so it is possible with my comings and goings I was generating drafts that impacted cooling.

I also dont have an enclosure, so they were at the mercy of the room, while not cold to me, was at 20C or so.....

I plan on picking up one of the pop up photo enclosures, and work my way up to a Lack enclosure later, so hopefully that will fix that issue.

Re: Final Layers Uneven in Corners

Well I got an enclosure...(photo tent) and my latest print seemed to come out fine! I always keep it cooler in my place, so that may have been the issue.

Re: Final Layers Uneven in Corners

An enclosure will certainly prevent many issues related to temperature and drafts and is a good start in troubleshooting.

That looks like a pretty large print and it is not unheard of to have minor bed level variances at the edges of the print bed. Most users experience issues at the back left and front right corners. This seems to be related to the bed heating cable at the back left corner interfering with the mesh bed level in some manner....

I suggest you obtain/create one of the full bed first layer tests to see (9 squares at all edges and the middle) and see. It does not take much variance to see the bunching you were getting at the corners and it can be successfully mitigated by bed level correction in the calibration menu. There is a knowledge base article on it and it does work and not that hard to do, but it takes some experimentation. My bed has -5 left and -7 back bed level correction and it has really improved the surface on larger prints.

Be forewarned, bed level and correction is a rabbit hole that can turn into an obsession for some 🙂 🙂

Re: Final Layers Uneven in Corners

An enclosure will certainly prevent many issues related to temperature and drafts and is a good start in troubleshooting.

That looks like a pretty large print and it is not unheard of to have minor bed level variances at the edges of the print bed. Most users experience issues at the back left and front right corners. This seems to be related to the bed heating cable at the back left corner interfering with the mesh bed level in some manner....

I suggest you obtain/create one of the full bed first layer tests to see (9 squares at all edges and the middle) and see. It does not take much variance to see the bunching you were getting at the corners and it can be successfully mitigated by bed level correction in the calibration menu. There is a knowledge base article on it and it does work and not that hard to do, but it takes some experimentation. My bed has -5 left and -7 back bed level correction and it has really improved the surface on larger prints.

Be forewarned, bed level and correction is a rabbit hole that can turn into an obsession for some 🙂 🙂

I appreciate the suggestion! I will try that now. I printed a large object last night, and while it was better with my slower print and enclosure I still got a slight amount of warping at the end. I will reply with how it all goes!

Re: Final Layers Uneven in Corners

Well, I rand about 10 of these http://www.thingiverse.com/thing:1776031 , and I think I have it dialed in, back and left -10, right-7, front 0 and I am getting much better adhesion. I have a print running now, so time will tell if it is enough, or I need to tweak more, but I got my tests sticking pretty well, so I am confident.

Re: Final Layers Uneven in Corners

Right on! Glad you got it worked out.

Attached are some STL templates that you can import into Slic3r PE, duplicate, move around, enlarge, shrink, etc to generate your own Gcodes for future testing. I gleaned them from the 50 page life z thread in the assembly and first prints subforum.

Re: Final Layers Uneven in Corners

Well I ran into a strange issue, my bed level correction was reset. I have no idea why that happened. I havent had any power outages, and it just happened today.....odd.

Thank you for the files though! So on a 9 square would I just split the difference if I saw a front or rear corner having an issue?

Re: Final Layers Uneven in Corners

Truthfully, I am not really sure, but you could try it. It does not take much to level it out, but does have some guesstimation in it. There is a knowledge base article on it.

I did my bed level corrections a few months ago so I do not remember exactly. But I am at Left (3) Rear (3) Right 11 Front 7. I wonder if it could just be Right 8 Front 4 to get to the same place.... I have three sheets and this works for all three so I really do not want to mess with it 🙂 . (1 Prusa PC and 2 Thekinggs)

I would do the 9 square test and let it run to completion and look at all the squares. In areas where the squares are thin or gapped, you need more negative in bed level correction. In areas with waves or ripples you need more positive in bed level corrections. I would first focus on the worst areas, do a correction, run the test again and see, rinse and repeat until you are happy.