Notifications
Clear all

Print Quality vs. Bed Adhesion  

  RSS
Fletch
(@fletch)
Active Member
Print Quality vs. Bed Adhesion

I received my print early this summer and I have printed a couple of things with varying degrees of success. Overall I am very happy with it but I am having issues with finish quality (as I call it). I have noticed others are getting really nice results and I am wondering what I could do to improve. So, without further ado...oh...all these prints were with the standard PLA that I received from Prusa.

Issue #1: I get what looks like rough drag marks as if the nozzle was too low and it leaves a "rough surface" on what should be smooth. When I noticed this, I did a live Z-axis adjust and it seemed to help but not completely...you can see in the corners that it still happens. (see issue1.png)

Issue #2: When running the V2Calibration.gcode file and using the finger test to see whether the first layer is adhering to the bed...I decided to raise the live z-axis adjust to try and eliminate the drag marks since that showed some improvement on the issue#1 above. However, it does not stick to the bed as well. The first layer was really good I thought but as you can from the residue on the bed that it pulled away from the bed on the corners. The print was generally pretty good but I am still getting these rough surfaces at the corners. This seems to be mostly with the fill and not with any border lines.
(see issue2-1.png, issue2-2.png, and issue2-3.png)

Clearly, I need to get the first layer of the print to stick better to the bed but looking under the microscope it looks flatter than it should but it sticks better than my last print. In short, I don't know much about tweaking the Slicer settings so I am basically just using the defaults but I have to assume that there is something I can do to improve the surface quality. Dimensionally I am very happy with the results. If I can just figure this out, I will be good.

Thanks in advance for any help or suggestions you might have.

Posted : 28/10/2017 6:06 pm
Fletch
(@fletch)
Active Member
Topic starter answered:
Re: Print Quality vs. Bed Adhesion

One other thing I noticed while preparing for my next print...In the picture issue2-1.png, the "residue" left on the bed has created an actual raised surface that I can actually feel with my finger. It feels like a really small bump with a smooth transition (mostly on the corners). I have not printed but maybe 5 o 6 prints in this general location and have never seen residual like this. I cannot even clean it off with alcohol.

Any thoughts? Is this bad?

Posted : 28/10/2017 6:41 pm
AJS
 AJS
(@ajs)
Noble Member
Re: Print Quality vs. Bed Adhesion

I highly recommend you read this thread:
https://shop.prusa3d.com/forum/original-prusa-i3-mk2-f23/printer-random-y-axis-travel-during-print-please-h-t6348.html

to get your Live-Z adjusted better. Cleaning the bed with pure IPA is usually good enough, but if you have some oils on it, a cleainging with pure Acetone is helpful.

The PEI sheet will self heal some once heated again. I would not sweat it too much.

--ajs

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 or loss. If you solve your problem, please post the solution…

Posted : 28/10/2017 7:19 pm
Fletch
(@fletch)
Active Member
Topic starter answered:
Re: Print Quality vs. Bed Adhesion

I am not sure how that link has anything to do with my questions or problems. I appreciate it though. I just saw some other 3D prints on the forum that looked like they didn't have this roughness or dragging issue and wondered if somehow I have something set wrong.

Posted : 28/10/2017 11:49 pm
AJS
 AJS
(@ajs)
Noble Member
Re: Print Quality vs. Bed Adhesion

If you prints are pulling up in the corners, or coming loose, you either have your Live Z set incorrectly, or your bed is dirty.

That link points you to a way to very precisely set your Live Z so the corners won't curl up. If they don't curl up, you won't get those dragging issues, and your print quality will be much better.

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 or loss. If you solve your problem, please post the solution…

Posted : 28/10/2017 11:54 pm
AJS
 AJS
(@ajs)
Noble Member
Re: Print Quality vs. Bed Adhesion


If you prints are pulling up in the corners, or coming loose, you either have your Live Z set incorrectly, or your bed is dirty.

That link points you to a way to very precisely set your Live Z so the corners won't curl up. If they don't curl up, you won't get those dragging issues, and your print quality will be much better.

Or, more likely I am complete idiot, and pasted the wrong link. Let's try that again.

http://shop.prusa3d.com/forum/prusa-i3-kit-building-calibrating-first-print-main-f6/-before-you-ask-troubleshooting-video-updated--t472.html#p39190

This link might be much more useful. Sorry. Computer did what I told it to do, not what I wanted it to do.

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 or loss. If you solve your problem, please post the solution…

Posted : 28/10/2017 11:55 pm
Fletch
(@fletch)
Active Member
Topic starter answered:
Re: Print Quality vs. Bed Adhesion

Thanks Aaron...this new link was much more informative. I was busy this week and did not get a chance to check back with the forum or do anything further. I will review this link in detail. In the meantime, I was trying to finish a project for my daughter's Christmas present (from last year). I can do it now that I have a printer. Anyway, I still have the same issues but the prints are functional. The last thing I was doing today was to try and make an adapter to attach my LCD monitor (with the broken stand) to a nicer stand. It is a bigger print than I have done before but weirdness prevails. I have attached a picture showing the progression of the print. I opted to quit this print after the first layer because I wanted to get a good picture of the problem and I realized that I made it too thick and wanted to make a change in my model.

Some thoughts on the previous comments...
1. I have tried to adjust my Z-axis (without Aaron's instructions...just on my own). The first pictures I showed were after I "raised" the z-axis and the result was lifted corners. My previous prints did not exhibit this behavior.
2. I clean the bed thoroughly with IPA before every print
3. I have done several things to calibrate my extruder. I think it is OK in that I am measuring a part with a single layer and it is within a couple of tenths of a millimeter. However, I cannot get a consistent 100mm length of filament to go through the extruder. It does not make any sense to me but dimensionally my prints seem to be OK.

Thoughts on my attachment:
1. The print started off with this wavy raised lines that look like something was dragging or like fabric that is allowed to pucker when it is not stretch tight during sewing. Then when it does the other side it looks close to perfect.
2. What causes those raised edges where two lines come together around a cutout? That was the only thing wrong on the second half of my print progression. I am theorizing that when lines come together from the opposite direction that the empty space is likely less than the line width that the filament is laying down and therefore you get an overlap. I just have no idea how to correct this if it is even the right explanation.

Again, I will go through the post you sent but I just thought I would throw this out if anyone has seen anything like this before. Thanks again!

Posted : 05/11/2017 12:00 am
AJS
 AJS
(@ajs)
Noble Member
Re: Print Quality vs. Bed Adhesion

A few things to check. (Go through the post I sent - really it will help and does not take long to do).

1) Check the tension on your extruder screws. Looks like they might be too tight and you are getting variable extrusion.
2) Looks like it needs a good XYZ Cal.
3) start the machine with your PINDA probe higher (or change your start GCODE to do this for you.)

M115 U3.0.12 ; tell printer latest fw version
G21 ; set units to millimeters
G90 ; use absolute coordinates
M83 ; extruder relative mode
M104 S170; Extruder to 170
M140 S[first_layer_bed_temperature] ; set bed temp
G28 W ; home all without mesh bed level
G1 X0 Y0 Z125; home X axis Lift to 125
M190 S[first_layer_bed_temperature] ; wait for bed temp
M109 S170 ; wait for extruder temp to hit 170
M104 S[first_layer_temperature] ; set extruder temp
G80 ; mesh bed leveling while rising in temp
G1 Y-3.0 F1000.0 ; go outside printing area
M109 S[first_layer_temperature] ; wait for extruder temp if needed
G92 E0 ; reset extrusion distance
G1 X100.0 E9.0 F1000.0 ; intro line
G1 X200.0 E12.5 F1000.0 ; intro line

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 or loss. If you solve your problem, please post the solution…

Posted : 05/11/2017 6:12 pm
Fletch
(@fletch)
Active Member
Topic starter answered:
Re: Print Quality vs. Bed Adhesion

Thanks Aaron! Stay tuned...

Posted : 07/11/2017 2:19 am
Fletch
(@fletch)
Active Member
Topic starter answered:
Re: Print Quality vs. Bed Adhesion

Update...(going step by step)
0) Belts are tight
1) Self test passed
2) My PINDA probe was a smigen over 1mm. So I used a metal spatula that measured 1mm and adjusted the probe so that the spatula would not go between the probe and the bed. I am guessing it is around 0.6mm from the probe tip. I did the XYZ calibration with no paper dragging and a perfect result.
3) This one I was confused on and read it many times but have some questions...
a) confirmed that the Live Z adjust was at 0.00 after the XYZ calibration
b) did the Z calibration
c) then I did the AUTO HOME
d) I don't know how I would know that the Z=0.15 after the home but I will take your word for it
e) I did the paper test while adjusting the live z axis adjustment. My result was a -0.570 the first time and then a -0.520 the second time (I will explain that later.
f) I backed off 50 and left it...so currently my live z axis adjust is at -0.470
4) I unloaded my filament and readjusted the screw lengths. Turns out they were a little longer than 14mm. While I was doing this the display kept telling me that the calibration was not entered. So, after I cooled things down I did another z calibration and live z axis adjust until I arrived at my present value.
5) then I downloaded the calibration surface from Jeff and printed it. As you can see it looks very uniform but the lines are not connected together. I was a little scared to adjust the z axis any further given that my paper was already dragging at -0.520 and I was at -0.470. So, just to clarify, you intention is that the live z axis adjust should be made until the calibration surface looks good correct????

On a side note, the lines are very uniform even though they are not connected. 🙂

Posted : 07/11/2017 4:28 am
Fletch
(@fletch)
Active Member
Topic starter answered:
Re: Print Quality vs. Bed Adhesion

Fortune favors the bold. I went ahead and live z axis adjusted to -0.600 for the first part of the print but it was hard to see whether I should go up or down. So I went up by 50 and here are the results (see attached picture). On the -0.550, there are some spaces between the lines if you hold it up to the light. There are no spaces on the -0.600 AND the thickness looks to be spot on. Would you say that this is good? I will try some more prints like the Prusa logo and the gears tomorrow.

Posted : 07/11/2017 6:11 am
AJS
 AJS
(@ajs)
Noble Member
Re: Print Quality vs. Bed Adhesion



5) then I downloaded the calibration surface from Jeff and printed it. As you can see it looks very uniform but the lines are not connected together. I was a little scared to adjust the z axis any further given that my paper was already dragging at -0.520 and I was at -0.470. So, just to clarify, you intention is that the live z axis adjust should be made until the calibration surface looks good correct????

On a side note, the lines are very uniform even though they are not connected. 🙂

Yes. You need to lower the Z value based only on the calibration test print, so the lines all connect and make a single uniform surface.

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 or loss. If you solve your problem, please post the solution…

Posted : 12/11/2017 10:53 pm
AJS
 AJS
(@ajs)
Noble Member
Re: Print Quality vs. Bed Adhesion


Fortune favors the bold. I went ahead and live z axis adjusted to -0.600 for the first part of the print but it was hard to see whether I should go up or down. So I went up by 50 and here are the results (see attached picture). On the -0.550, there are some spaces between the lines if you hold it up to the light. There are no spaces on the -0.600 AND the thickness looks to be spot on. Would you say that this is good? I will try some more prints like the Prusa logo and the gears tomorrow.

Yup, that looks good. And I think you will find much better bed adhesion and print quality with this new setting.

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 or loss. If you solve your problem, please post the solution…

Posted : 12/11/2017 10:54 pm
Share: