Need help calibrating
Hello!
I completed my build early this morning and I've spent all day with very mixed success printing. I believe I have multiple issues, but I'd appreciate some input from others.
I'm not very confident that I'm calibrating the Z-axis correctly. At times I think I'm too close, and others not close enough. I'm adjusting the bed to where I can slide the card under the extruder but touches. It seems to take me ages to get all four corners adjusted. I'll get to where I think one is right, then I'll adjust another one and then it seems the first one isn't right anymore. For a while I was having an issue where the Y-adjuster wouldn't rest on the Y-carriage. I could press it down and the adjuster would touch the carriage, but as soon as I removed my finger it would jump back. Completely removing the heat bed and placing it back down on the carriage seems to have resolved that issue for now.
The print won't consistently stick to the glass either. I'm not sure if this is related to the level issue or not. Right now I can't get anything to stick for anytime at all. In the morning I intend to to buy some hair spray if I can't find any specialty spray at Micro Center. At one point I thought I had everything perfect and I had a print going for a little over an hour. At some point after the hour mark, and 24% in to the job, the print came unstuck to the bed and naturally a complete mess was made.
I've attached a photo from the first layer of a recent print. I think the box on the right is perfect, but the box on the left obviously has some issues. Any ideas on what is causing that? I tried to get a good picture of the line that is printed close to home with the printer first starts, but the prints were to blurry to see. What is happening there though is the line looks find at the start, but seems to get flat towards the back. Does that indicate that my bed is not level and closer towards the back of the bed than it is in the front? Also, The extruder often hits the clips that are holding the glass down when the job starts. Is there something I missed that will prevent that?
Thanks for the help!
Re: Need help calibrating
First off are you calibrating with the bed heat on? Everything needs to be at the proper temp for you to calibrate the bed. Be careful working around the extruder and the bed. Also make sure the 2 Z-axis have the spacing because one side can get higher than the other.
Also you need to use some glue or ABS juice for good adhesion plus never touch the bed because it will leave oil from your fingers on the glue.
Re: Need help calibrating
To add to Scott's comments, make sure that your frame is square - that all 4 feel are in good contact with the table.
This is a major cause of calibration issues. If it's not square, get that sorted and calibration will be much easier.
Having said that, initially most people find calibration difficult to start with, but you will learn and it will get easier. After many hours of frustration, I now calibrate in about 10 seconds.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Need help calibrating
Well, I've touched the glass give or take 50,000 times, so that's probably not helping. Thanks for the "don't do that" tip! I'm doing a small print right now, but when it's done I'll take the calipers and measure both sides of the Z-axis to verify that they're the same. I did use a level yesterday and it seemed right.
Thanks for all the help!
Re: Need help calibrating
I've been running for a couple of weeks now and using the printer daily. I've had a lot of really great prints, but I'm still not at 100%. If I print something that uses most of the bed, I have issues with parts sticking. So here's what I've tried:
* I checked the X-axis. I noticed that while all four felt corners touch the table, so did the Y-axis frame. I loosened the X-axis bolts and managed to move the frame a bit. Now the frame doesn't touch the table.
* I checked both Y-axis to ensure that they were level. One side was off by a couple of millimeters, but using my calipers I'm pretty sure that they are corrected now.
* I applied pressure on cross sections of the frame to help ensure that it was straight. There was no movement at all.
* these adjustments of course meant that the bed needed to be re-leveled. The bed was now sitting quite a bit lower than before, so I had to raise the bed with the adjusters quite a bit. After calibrating each corner I now again have the issue where one corner pops up when pressure is applied to the opposite corner. Right now I've used a couple of wire ties to hold them down and it seems to be printing well this way, but this is obviously less than ideal. What should I check next? Is it possible that my heat bed is warped? I feel like I'm in an abusive relationship. I love this printer and most of the time we get along great, but sometimes it sucker punches me in the gut.
Re: Need help calibrating
Hi scoco,
Just a quick question, why is not the frame supposed to touch the table ? I'm reading as much as I can to learn, but haven't seen any mention anywhere recommending that.
Regarding your issue, I am experimenting more or less the same, with heatbend bending, but I have a way better situation now.
What I have done was to loosen the screws maintaining the HeatBed, made it heat it up to 100 °C, let it some time so that he could dilate as needed, and while maintaining hot, then I tightened the screw again. I believe one of the issue is that the dilatation of the HeatBed is not the same as the support plate, and since everything is build while being cold, the screws are not well positioned, that could generate mechanical tension during heat.
I'm like Jon Snow, I know nothing.