Prints pulling up at corners

[jimc]

yes, in your process settings, gcode tab, global offsets. they should be all zero. you dont want to set the z-stop on the machine when your applying an offset to it in the software. you need to set the machine correctly first. i personally never use the software to make bed gap changes. i prefer to do it on the machine. this way i dont accidentally load a profile setting and have some kind of offset applied and wonder why things arent going down right. i found that taking the z-stop bolt and putting it from the bottom up with the jam nut on the bottom as well then a nylock nut on the tip with the threads just set into the nylon. the nut will contact the switch. this let me get the bolt setting really close and i can make quick adjustments with a small 7mm wrench just by rotating the nylock nut slightly. every 1/2 flat on the nut will move the bed .05mm

[naturalstate720]

to set your bed gap, in s3d be sure your first layer height and width is set to zero. also be sure your gcode offsets are all at zero. start with a .005" feeler gauge and adjust the z-stop bolt with the extruder at bed center so that you have a light drag. do a test print and on the first layer see if the extrusion edges are touching. do the extrusions look round? they should look ever so slightly flattened. if the are round then you need to go tighter. if the extrusion is too fat and really wide then you need to increase the gap.

How can I make the first layer height & width zero?
It only let's me go down to 1%, it can't go to zero? Or am I looking at the wrong place? This is under the 'Layer' tab under 'First Layer Settings'. Currently I have:

FIrst Layer Height: 90%
First Layer Width: 100%
First Layer Speed: 50%

[naturalstate720]

In another post I think I read that 100% is 0. That's pretty confusing. Is that correct?

[jimc]

huh? 100% is not 0, it is 100%. if you made a first layer height and width zero then you would have no first layer. put those settings to 100% and leave it alone.

[naturalstate720]

Then why did you say set them to zero?
This is what you said in an earlier post " in s3d be sure your first layer height and width is set to zero."

[jimc]

Haha oops. The gcode offsets are zero. The height and width are at 100%. Sorry about the typo and confusion

[SouthSideofdaSky]

For what it's worth, I have been printing PLA with the following temperatures and bed settings and haven't had any issues with the prints pulling up at corners in a long time:
- Extruder temperature 215 C
- Bed covered with blue painter's tape, and ALSO heated to 70 C at beginning of print, decreased to 50 C at layer 5
- Bed fan at 100% at layer 2
- Plus the z height set correctly. Like jimc said your first layer should look somewhat flattened on the bed. Whether you achieve that perfect height in the software or the actual machine, is kind of up to you.

Like someone else said, 3D printing is an imperfect science so sometimes different things work well for different people. Part of the fun is figuring out what works best for you.

[naturalstate720]

I honestly feel like throwing this thing off the balcony. I've been d*cking around with this thing for two weeks spent dozens of hours reading a myriad of posts and don't feel like I'm getting anywhere. Already been through an entire roll of filament without any models that we are happy with.

I spent like three hours trying to get the zstop bolt perfect, what a pain. I can't fathom why it was designed to be so hard to tighten. I realized that the bed is not level (ready to print out of the box?) and got it leveled with .006 feelers.

Sprayed the sh*t out of it w/ hairspray. Prints are now not even sticking at the beginning. I never had that problem before. And now I've got problems with the nozzle, that I never had before. When it starts to print it's like two peices of thin filament are coming out of nozzle. I try to pull it out with tweezers and it becomes one before it starts to print the skirt.

I don't know where to go from here.

[Bratag]

I honestly feel like throwing this thing off the balcony. I've been d*cking around with this thing for two weeks spent dozens of hours reading a myriad of posts and don't feel like I'm getting anywhere. Already been through an entire roll of filament without any models that we are happy with.

I spent like three hours trying to get the zstop bolt perfect, what a pain. I can't fathom why it was designed to be so hard to tighten. I realized that the bed is not level (ready to print out of the box?) and got it leveled with .006 feelers.

Sprayed the sh*t out of it w/ hairspray. Prints are now not even sticking at the beginning. I never had that problem before. And now I've got problems with the nozzle, that I never had before. When it starts to print it's like two peices of thin filament are coming out of nozzle. I try to pull it out with tweezers and it becomes one before it starts to print the skirt.

I don't know where to go from here.

Ok Ive read through this thread now and there are some good points in it. If you are getting a split filament then you could possibly have a nozzle blockage, not unlikely given how much stuff you have been spraying on the print surface etc. Do a cold pull of the nozzle and make sure its clear - or run through some cleaning filament.

Ok now on to my questions.

1) Are you still printing on glass, if so ditch it and get a MIC6 aluminum plate, there will be an outcry here how you don't need it , but my large flat prints were significantly less warpy after
switching to mine, because the heat distribution is far more even and WAY less prone to variations due to atmospheric changes like the AC switching on.

2) Leveling the bed is crucial - I personally think more so than getting the distance of the print head correct. You can adjust the print head distance using gcode offsets , you can't adjust for an out of true bed. One tip that helped me a bunch when leveling the bed was to tighten all the leveling bolts as far as they can go, set the Z-stop distance in the nearest corner of the bed and then level (I am assuming by now you know the order of the corners you should level through). This way you are only ever loosening the bolts and don't get into an endless loop of tightening and loosening. The feeler gauges are great but don't underestimate the good ole eyecromiter (can't remember who coined that term), I slide the bed back and forth and watch the print head, you will get adept at seeing variations in the bed.

3) Check out the beta auto leveling thread. I will never go back now that I have it installed. While it might be possible to get better results with a God like leveling of the bed, the auto leveling works very well in 95% of cases and guarantees accuracy and speed of model -> finished print.

I can understand your frustration and believe me when I say we have ALL been there at some stage. The early printers (at least the ones I had) had bed leveling systems straight out of a nightmare and many a four letter word was said after a print lifted from the bed after 4 hours or so.
You just gotta have faith that it is possible to get the bed level and get good prints. check out some of the showcase prints for proof.

PS: I suppose it was determined that the actual glass is not buckled?

[naturalstate720]

And sorry to sound like a weenie.

Well I'm in the middle of a print right now. Printing a building that we need to do for work around 5" x 2". It's sticking and I pulled off the double plastic nozzle extrusion before skirt was laid down and it seems to be going down nicely and packed together on bottom layer, kind of squashed.
Looks like a support got knocked over, but maybe I have the diameter too small on those.

Now I'm noticing that the fan isn't coming on. I know I didn't change any fan settings. And temp is still set to 60.

Thanks for the response Bratag.
I'll look into the plate. I've seen that auto bed wizard before. But thought I read that it wasn't as good as doing it manually. I feel like we got the bed leveled good earlier though, but I'll check it again.

I can already ever so slightly see one of the corners not sitting flush on plate. But maybe this is because fan is not on. I do have a desktop fan blasting right next to it though.