My Prusa i3 Mk2 has _never_ printed right. Please help!
I bought a kit several months ago and have never got it to print correctly.
My current problem is that the printhead starts to drag, especially in the back-left corner, around 1cm into the print. Does anyone have some suggestions, because I'm getting pretty depressed about my investment.
Thank you sincerely and humbly in advance for your time.
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
Is your z frame perpendicular to your bed ?
Are both Z frame motors stiff to turn when powered ?
You must always recalibrate when either of the Z motors have been moved.
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
I didn't know that about recalibration, I will give that a try, and check the perpendicularity of the axis as well.
If this fixes my issues, I owe you a big one. I think I am not very smart for waiting so long to try looking for help here on these forums.
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
I didn't know that about recalibration, I will give that a try, and check the perpendicularity of the axis as well.
If this fixes my issues, I owe you a big one. I think I am not very smart for waiting so long to try looking for help here on these forums.
Well, its a quality in itself to first try and solve problems yourself, but its also good to seek help if that doesn't get you anywhere.
There are a lot of people with a very firm understanding of the MK2 here, and I bet you get it running soon 🙂
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
If can explain a little better what I meant about the z motors being moved -
The 2 z motors always turn alike. If you accidentally or deliberately move one of them the x axis will not be parallel with the bed. Often this stops the bed probing from working.
The calibration instructions tell you to keep moving the Z until both motors are skipping at the top to set an assumed equal distance from the bed for both sides and from that point onwards the motors will always turns equally.
If you turn one side or the other side independently it will appear to the bed probing as if the bed isnt level - I'd be surprised if this caused the nozzle to hit the bed - just either fail to probe or adjust its bed mapping.
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
andrew,p2 is right. You must raise both Z axis screws via the motors to the top of the frame. The noise is scary but is good. In original calibration. I repeat as I and others have said before, you will do no harm to the 3D printer. Both sides must top out and hit the ends.
Nigel
Life is keeping interested and excited by knowledge and new things.
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
On the one hand, I uncovered two problems thanks to the advise here: my Z-Axis frame was not fully seated on one side, so that is now addressed. Also I had the guides on the top reversed (the left one was upside down and on the right, and vice-versa). These problems are now addressed!
On the other hand, I ran a print last night and it still did not come out "full height" and there are clear signs that the print nozzle was dragging (the top is very rough). I am not going to rule out that there was a problem generating the gcode, so I'm printing something else to see if there is the same problem.
Can anyone think of any other reasons the Z-axis would not be moving up properly, especially after the first .5cm or so?
Thank you all again for your encouragement and advice.
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
I've attached an image of some prints. The left (smaller) print is a small sub-section of the larger print I am attempting. It came out great. The one on the right (larger) is the print from last night. You'll notice it's significantly shorter, and it's very rough at the top, almost like the z-axis is just stopping after a certain point.
Both were made from the same model, with the only difference being I cut out 90% of the model to make the smaller piece. My next step will be to regenerate the gcode to see if there is a problem there, unless someone can think of a problem with the printer I could troubleshoot.
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
I wrote a longer reply but it dissapeared when my mobile hot spot dissapeared...
so lets try a short reply...
is this worse on low power mode?
if you turn the power completely off, does the X carriage move up and down by hand?
if not it may be due to the screws on the ends of the X carriage, smooth rods (right hand side) being too tight or too loose
other issues may be more difficult to address!
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
Are you using the 'Z Hop' slicer profile?
if so... try the colour profile...
I normally use Simplify3d, but in the past... when I tried Zhop in Slic3r it seemed to lose vertical alignment!....
the surface roughness on the larger piece is possibly due to over extrusion because the printer thinks the extruder is moving higher than it actually is moving! and therefore the extruder is pushing say 10mm height of plastic into an 8mm high model...
regards Joan
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
Are you using the 'Z Hop' slicer profile?
if so... try the colour profile...
I normally use Simplify3d, but in the past... when I tried Zhop in Slic3r it seemed to lose vertical alignment!....
the surface roughness on the larger piece is possibly due to over extrusion because the printer thinks the extruder is moving higher than it actually is moving! and therefore the extruder is pushing say 10mm height of plastic into an 8mm high model...
regards Joan
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
Thank you for the reply!
It is difficult to tell in the pictures I posted, but the overall height of the smaller print is correct, whereas the larger print (where the scraping occurred) is "smooshed", and is only about 2/3 as tall overall as it should be. I can't yet tell if the smooshing takes place only in the last third of the print, or if it starts happening at some level.
I just did a "Marvin" print and it looks pretty good! This means that either there is a problem with my slic3r settings, or a problem when I print objects with large footprints (maybe something that only shows up a couple hours into a print?)
Thank you again for all of the feedback and suggestions. What a great community.
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
When I originally got my printer, I never could get the slic3r program to install properly. (I don't remember if it comes on the SD card, or if I downloaded it from the website). Either way, I ended up downloading slic3r from from slic3r.org, and I've been trial-and-erroring the settings since the beginning.
I just went downloaded the Prusa version, and I have a test print going on one of my own models with the "0.15 OPTIMAL" slic3r presets, and it's going great so far. If this print finishes ok, I'll re-slic3 the model that's been giving me the most issues and see how that goes.
I don't think I can truly express how grateful I am for all of the help you all have given me (and probably are yet to give).
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
Well you should better install the Slic3r version included in the driver package, there are specific settings embedded and some additional features:
here: http://www.prusa3d.com/drivers/#_ga=1.45582884.1220107311.1455720235
I'm like Jon Snow, I know nothing.
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
Holy cow, I'd say there must be some special settings! I'm used to gcode generation being almost instant. I'm sitting here going on 30 minutes now on my most recent attempt with one of my models, with the Prusa-supplied version using the "0.15 OPTIMAL" preset (is it frozen? is it thinking? Dare I abort?). The progress bar hasn't budged in at least 10 minutes.
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
after a print where one side seems to not move up as much as the other, can you verify this by moving Z to the top - without maxing it out and compare the distance from top of both sides - remember calibration starts out with the tops of both z sides being exactly level with the top.
If one side is lower then the other then you need to determine why - duff motor ? slipping screw ? stiff screw causing motor skipping etc.. etc...
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
Brian, I'd like to echo what Joan said. It looks like the Z axis is not moving as much as it should, leading to over-extrusion (thus the rough surface) and making models too short. Possible causes:
- Is the electrical connection to the Z steppers intermittent? The Z motors should be active at all times when the printer is on, making them difficult to turn by hand. If either one is easy to turn while the printer is on, there's an electrical problem.
- Can the motors move freely? With the printer off, you should be able to slowly raise and lower the X carriage by pushing it up or down (with a bit of careful force). If it binds somewhere, you probably need to realign something.
Re: My Prusa i3 Mk2 has _never_ printed right. Please help!
Stop printing your complex large own model and print something small.
"Benchy" for example.
Even better, print the frog (or something else) that came as .gcode file with the printer on the SD card.
That will show you if the printer works properly or not, when it is being fed a good file.
If you design and slice your own file, then there are many more possible problems to troubleshoot.
So narrow it down until you know that your printer works 100% fine, then produce your own .gcode files.