Tried everything, can't get bed level.  

Re: Tried everything, can't get bed level.

Babak

I have no problems with your comments. It is often the case that I am wrong and I have no issues with that being pointed out.

I think however in this instance we shall agree to disagree; I really don't have the time and energy to explain 😉

Peter

EDIT: Just a thought - the firmware we are using is identical yet it behaves differently on different printers. Why would that be?

Re: Tried everything, can't get bed level.

EDIT: Just a thought - the firmware we are using is identical yet it behaves differently on different printers. Why would that be?
General rule - if the software behaves differently on different printers, the only possible reason is that not all the conditions taken into account are the same. 🙂

Re: Tried everything, can't get bed level.

David

Absolutely. So if you make the 2 printers the same with regard to the user-changeable settings and there is still a difference in operation, then there is only build and environment left, and those two things are more difficult to assist with, so we start with the simpler things first.

Peter

Re: Tried everything, can't get bed level.

I am not sure whether the infrared bed sensor works better than the induction sensor. What is the trigger distance of the infrared sensor? How reliable is the infrared sensor?

The problem with the induction sensor distance is following:

The sensitivity of the induction sensor depends on its size and the size of the induction sensor target point on the print bed. If one wants to increase the gap between the print and the induction sensor, she/he needs to use a probe with a higher diameter tip (it contains half of a pot ferrite core with a magnetic coil) and a bigger sensor points on the print bed. Bigger sensor points mean less even heating of the print bed.

If you have problems with the PINDA probe knocking into the print, you may try the hat
http://shop.prusa3d.com/forum/improvements-f14/pinda-hat-mk2--t1020.html
and/or fixing the PINDA probe slightly higher. You should be careful though when mounting the PINDA probe slightly higher to make sure the print nozzle never touches the print bed during any calibration procedure.

Vojtech

Re: Tried everything, can't get bed level.

EDIT: Just a thought - the firmware we are using is identical yet it behaves differently on different printers. Why would that be?
General rule - if the software behaves differently on different printers, the only possible reason is that not all the conditions taken into account are the same. 🙂

Precisely.

In this case, I contend that the issue is variances in the induction sensing system in manufacturing, possibly in the print bed itself. Another reason could be that the firmware's mesh bed leveling is actually not working correctly, but other beds are flat enough that it doesn't matter, where as mine may have been manufactured slightly differently.

Moving the probe itself shouldn't affect this problem at all, as the trigger distance between the face of the probe and the bed should theoretically be the same no matter what the relative position of the probe is to the nozzle. The Live Z adjust is designed to account for the static offset, and the operation of the printer should not change if offset is -1mm or -.2mm.

Re: Tried everything, can't get bed level.

I've posting about this in the facebook group where others are experiencing this issue. Prusa sent me a new bed to try, which changed nothing. As the nozzle passes the mid point on the bed, it gets progressively less squished. I have tried the newest firmware and my axis are all perpendicular, perfect. Endlessly played with the probe height, washers under the bed, you name it. I actually did not yet try resetting the bearings under the bed, I'll do that.

Quite frankly, I feel that I've done my due diligence regarding this issue. I think there are enough people with this exact issue to say that there is in fact an issue with some of the MK2's out there. Honestly, I'd live with it if I could print trivial stuff like a 100mm quadcopter frame without the left side lifting every single time (yes, I clean my bed with alcohol). I've dumped hours of my time trying to solve this on a brand new printer and at this point I'm done. The way I see it, a replacement or refund is acceptable at this point. I am more than willing to send my printer back to Prusa mostly assembled for analysis, in exchange for another (prebuilt) unit.

Re: Tried everything, can't get bed level.

Having similar issues here on a prebuilt one. The only way I've gotten good prints so far is to move to a corner of the bed rather than the center, as the difference in certain areas is too much around the center. And the difference is clearly visible if I go to home on the printer and then move along the X axis, there's an obvious difference in the distance from the bed as the nozzle moves.

Also have tried 3.0.5 (which 1 time out of 20 or so attempts at calibration, bugged out on me and ruined my PEI at the bottom edge). I'm seeing slightly better results on the older 3.0.3, but not much.

Re: Tried everything, can't get bed level.

I am so glad others are finally speaking up more. I am becoming tired of Prusa's non-acknowledgement of this issue, and unanswered emails.

Re: Tried everything, can't get bed level.

I am experiencing the same difficulties and support from Prusa has been so incredibly unhelpful an condescending. I have spent the majority of three days trying to get my printer working again. I has disassembled and reassembled the entire printer TWICE with digital calipers. I have gotten ONE succesful print, and when I went to start the new job, it rammed the extruder into the bed. After waiting days for a response from support their only response was more or less "are you sure you put it together right?" The MK1 left a great taste in my mouth. After this nightmare I never want to do business with the company again.

Re: Tried everything, can't get bed level.

It's bizarre how some people are having all these problems, yet others (like myself) had no issues at all!?!? I wonder if a batch of them had an unspotted common fault? A few suggestions, which I'm sure some of you have already done:

Have you tried to find a way to check ALL the supplied parts are straight and flat?
Check all the fixing holes in the y-carriage and heatbed are the correct distances apart and line up.
When calibrating have you watched the light in the probe for whether it comes on/off at the right points/distances?

What's odd is those who have managed to print something perfectly once, then it goes again?! It suggests something is going out of alignment due to either vibration or possibly a motor problem?

Re: Tried everything, can't get bed level.

The problem is that printer design allows too many possibilities of mechanical imperfections. 0,1mm here 0,1mm there, add some software bugs and issue comes out.

Re: Tried everything, can't get bed level.

I think my bed is very slightly misaligned between right/left such that prints towards left will detach from bed unless I use glue stick on left side. With glue it sticks and prints turn out great with 3.0.2 fw.

Re: Tried everything, can't get bed level.

I think my bed is very slightly misaligned between right/left such that prints towards left will detach from bed unless I use glue stick on left side. With glue it sticks and prints turn out great with 3.0.2 fw.

Question: What Z Live Adjust value are you running at? And what firmware?

Thanks in advance

Peter

Re: Tried everything, can't get bed level.

I think my bed is very slightly misaligned between right/left such that prints towards left will detach from bed unless I use glue stick on left side. With glue it sticks and prints turn out great with 3.0.2 fw.

Question: What Z Live Adjust value are you running at? And what firmware?

I am using 3.0.2 fw with -.457 z live adjust but I adjust that slightly depending on filament.

Re: Tried everything, can't get bed level.

OK, thanks.

I was getting the same problem with early firmware and when I had used only the Live Adjust to set the nozzle gap.

Unfortunately, I am not sure what fixed the issue with me, because along with upgrading my firmware, I also reduced the live adjust down to zero by precise adjustment of the nozzle.

This is possible to fix and that it may not be a build issue. Just depends on how much time and effort you want to throw at the problem.

Peter

BTW, How's your Eiffel Tower? Mine is now printed; just waiting for clean-up and assembly.

Re: Tried everything, can't get bed level.

BTW, How's your Eiffel Tower? Mine is now printed; just waiting for clean-up and assembly.

New silver filament getting delivered today so my testing can continue. Can you post your Eiffel Tower in hall of fame section? I have some questions and would like to see final result.

As for bed leveling, I'm still aiming for perfect but it's close enough now that I'm happy. As long I use glue stick so left side "sticks" prints come out perfectly to my eye. Lots of learning. For example, I realized by setting nozzle to 215 for first layer and 205 elsewhere, prints come out even better than before for some reason. I just copy what the experts do like yourself. Thanks.

Re: Tried everything, can't get bed level.

I'm cautiously optimistic about 3.0.6 having fixed my issues. Only got one print started so far, but it's working so much better than the others I've tried.

Re: Tried everything, can't get bed level.

I have been having similar issues with getting my bed level. The i3 MK2 is my first 3d printer, so I expected a bit of a learning curve. I have checked and rebuilt my y-axis two times, and will prob do it a 3rd time trying to get everything perfect. I do believe some of the issues is in the actual design of the machine. No matter how perfect the y-axis is, the bed is sitting on bearings, fastened with zip ties, so I think its an uphill battle on getting the bed perfectly level. Plus as others mentioned the slots in the frame can introduce other calibration issues.

I do disagree with the complaint about PRUSA's email support. I have sent them several emails about various issues I have had, and while it did take them a couple of days to get back to me, they did respond. The fact that they are in Ukraine and still manage to respond in a couple of days, is fine with me. Also the forum support is amazing. There are many people on these forums who are helpful, and most of them respond in a matter of minutes!

Since installing FW 3.0.6RC2, some issues have been resolved like the X/Y calibration. However, I am still having the same left/right side of the bed that many if you guys are having, which I would assume would be fixed with Z-calibration, firmware update. I am hopeful that PRUSA will refine Z-calibration soon, like they have done on X/Y.

Part of the fustration with Z-calibration is everytime I run Z-calibration, different numbers show up for my 9 sensor points. Also the same numbers have a huge range, even when running the same calibration back to back. Some points can be 1.83, then that same point can be -2.32! Even when its somewhat close in range, I never get the same numbers. And this is all without me even touching the PINDA prob or making any adjustments. At this point I am terrified about touching my PINDA prob any more, because it least now, its not smashing into my bed creating divots and scares.

My biggest suggestion to PRUSA or any innovative members of this forum would be to create a modification for the bed to use bed leveling screws with springs in it like most other printers. I think with some manual adjustments of the bed, along with the PINDA prob, and X/Y/Z calibration together, it would solve the uneven bed issues.

I have been researching M3 screws with a built in spring, however, there isn't a lot of space under the bed, before any screws would start to hit the frame as the Y-axis moves back and forth. If someone can figure out a modification, I would love to try it.

~Kaizers

Re: Tried everything, can't get bed level.

Kai

Firstly, it's Czech Republic.

Secondly, it is known that running the calibration more that one produces strange results. This has been addressed in 3.0.6.

Thirdly, don't use springs on the bed; they introduce the potential for lateral movement.

The Mk1 had a bed fixed to the chassis with adjuster screws. Many new users complained about not being able to level the bed.

Personally, I have all 3. A Chinese clone with springs, a Mk1 and Mk2. The Mk2 with 3.0.6 is now working significantly better than the other two.

Peter

Re: Tried everything, can't get bed level.

I had this issue but fixed it with a magnetic shim.

http://shop.prusa3d.com/forum/original-prusa-i3-mk2-f23/calibration-problem-t940-s10.html

Check the link for what I did

I didn't mention in the other post the exact type of blade, but here you go, for reference.