[Chiuso] Print Issues (with picture)  

Re: Print Issues (with picture)

Im struggeling with first layer settings as well, since two days now.
It looks on your print as its way to close to the build plate.

I have the similar problem. I live adjust the Z axis until the first layer seems to stick just fine, but with that setting the second layer are plowing through the first layer, so I have to live adjust it and raise it a bit... Really strange.

I just did the Extruder Calibration:
And I adjusted my Steps/mm some, it extruded 94 instead of 100mm filament, after I changed the Steps/mm value in the FW it looks better, but I have the same issue with my first layer...

Re: Print Issues (with picture)

I'm at my wits end, I spent most of today trying to get it to work and still nothing. I even took a chunk of it apart and re-aligned the bolts, and the results are the same. I started thinking maybe it's the PLA, so I opened up my new pack of ABS and tried it, and the result is pretty much the same. I changed the heatbed and extruder settings in Slic3r for the batman logo to work on ABS, and this is what I got.

The corners and certain parts you can see that are white underneath is where it is coming off the heatbed. I had to stop the print when the right side completely peeled off. Do I have a defective heatbed? It looks like both the PLA and ABS issues are happening in the same spots on the heatbed when you compare them.

Re: Print Issues (with picture)

Hi Damian,

this is a bit strange, trying to figure what could be the issue.

Could you explain with more detail how you clean the heatbed ?

Re: Print Issues (with picture)

What do you use to clean the print surface? We found out not all the brands of windows cleaners work equally. You can try using IPA for cleaning or even the glue stick to get the first prints going

Re: Print Issues (with picture)

I'm using plain old windex, but I tried with liquid dish soap also and no difference.

I finally gave up trying to print the batman logo and loaded up a model with a circular base, and added a raft for better adhesion. It started fine and after 2 hours in it was late so I went to bed hoping it would continue to print well. I woke up with a huge mess of ABS filament and the object on the floor. (Last image in link) I tried printing it again after I cleaned the mess, seemed fine for the first hour, so I went to the hardware store for something, came back half an hour later and it was printing a huge glob in one spot on the model. (Second image in link) It didn't even get as far as the first time around without messing up. I tried printing this same model earlier with PLA and it got further until the supports Slic3r created got snagged on the extruder and snapped off, so I had to stop the print. (The blue PLA in the image)

Point being, it seems this printer is getting worse each time I use it, if it's not the adhesion to the heat bed it's some random screw up that I wouldn't even know where to begin diagnosing. I'm trying one final print of this model, and I lowered the z height a tad for better adhesion and used the glue stick, but I have no confidence in this working either. How is it that it can print okay for more then 2 hours on a rather uncomplicated circular object then just totally mess up twice now? I'm wasting a LOT of filament as you can see in the background of the image, just trying to tune this printer or having it fail in the middle of a print.

Also, the last time I stopped the print the extruder did not return home, so I guess the latest firmware did not really fix that issue either.

http://imgur.com/a/BoXU6

Re: Print Issues (with picture)

To follow up, the print did actually finish and the only changes I made were lowering the z height slightly, raising the nozzle temp 5 degrees, and using the glue stick.

It seems all the problems I'm having are being caused by the heatbed. I read that every new layer of ABS likes to pull on the layer below it and tends to warp if not secured properly. I looked at the 2 failed prints and sure enough they base was warped because the heatbed did not them down. This makes sense because if the sides warp eventually the nozzle will hit the plastic on whichever layer it's currently at and the print gets knocked off the heatbed.

Now the question is why is this happening? One of the selling features of this printer is a "Hassle free PEI print surface" which I was told does not require a glue stick. What I noticed with the heatbed is that it tends to retain the outlines of previous prints. If I run my fingers on it, it does not feel perfectly smooth, and when I print something with a larger flat surface area, I can see imprints on the bottom of it from previous prints I have made. It made me realize this is most likely why it seems the prints are getting worse. When I assembled the printer initially, quickly tuned the z, and printed out the batman logo it came out great with no problems. Now with all the slight hills and valleys from all the prints I've made, new prints are having a harder time sticking to the PEI heatbed, so even if my Z height is great, it doesn't matter if the filament pulls off because it goes over a valley somewhere on the heatbed while on it's first layer.

I'd like to know if others have noticed the same thing happening after having used the printer for a while.

Re: Print Issues (with picture)

I'd like to know if others have noticed the same thing happening after having used the printer for a while.
No. I've been printing on MK2 for 3 weeks almost non-stop and the surface of the bed is almost untouched except few scratches caused by my clumsiness.
But I haven't printed from ABS yet. Will try today maybe tomorrow.

Re: Print Issues (with picture)

Hi Damian

Ditto what David said.

Printing ABS requires a more stable environment than with PLA and I wonder if you are having issues with drafts? ABS likes a nice still warm environment (like Josef's print farm) otherwise it will start lifting at the edges of the lower layers.

It may be that it is sticking to the PEI and when it lifts it is pulling the PEI up with it; the heat and pressure is then deforming the PEI to the shape of your model.

Try putting a large box over the printer while printing; cut out a window in the front so that you can see what is happening. And make sure the part fan is turned off throughout the print.

Peter

Re: Print Issues (with picture)

I don't have any drafts where the printer is, it's the corner of a finished basement with closed doors/windows. It would be one thing if it was just the ABS, but even the PLA doesn't stick like it used to anymore. Doesn't seem to matter if I lower the Z to squish the PLA more to the bed or raise it higher. It used to stick, so how else can I explain why it doesn't anymore? and why the heatbed is PEI is no longer perfectly smooth?

Re: Print Issues (with picture)

Hi Damian,

I've been printing with PLA, ABS and PET, and have no sticking issue, not used Glue tube nor ABS juice.

I had issues at the beginning that was fixed by spending some time to make all axis perfectly perpendiculars, and by finding the right Z-Offset. I have some marks on the PEI, two circular due to the first calibration gcode printed too close, and a horizontal scratch. But this does not prevent my actual print to stick to the bed, and it seems to gradually fade away.

The area shown on your batman prints are a bit strange. They are not geometrical enough so that it could be explained by axis issue. The only thing I could imagine is an issue with what you use to clean the surface, which may leave some unwanted substance, or which alter PEI. Did you use the provided isopropilic alcohool pads ? Did you use something else ?

Re: Print Issues (with picture)

Hi everyone 🙂

Sorry, but what is the Z-offset and how it is used? 🙄 I have MK1 and do not use it. But i have been waiting for MK2 upgrade kit 😀 wanna know beforehand.

Thank you!

Re: Print Issues (with picture)

I've been printing on MK2 for 3 weeks almost non-stop and the surface of the bed is almost untouched except few scratches caused by my clumsiness.
But I haven't printed from ABS yet. Will try today maybe tomorrow.
Tried ABS. Almost the same as PLA. Sticks like hell. Printed about 10cm long part, it tends to warp on longer ends, but only about 1/2 mm. It sticks so well I can even lift whole printer by holding printed part. The part can be removed easily after cooldown. Almost invisible traces on surface of the bed completely disappear after next heating.
I'll try to eliminate slight warping by increasing bed temperature and decreasing HE temperature. Now it's 255/100, I'll try 240/110.
Conclusion: PLA and ABS works for me, no glue, no juice, just clean dry heatbed.

Edit: ABS need change of Z-adjust. For PLA I have -0.355, for ABS I had to go down to -0.470. Maybe Z-probe has some temperature dependency.

Re: Print Issues (with picture)

I have the same problem with the blisters. After some of the prints, I could also feel tiny hills and valleys with my finger tips, like destribed before.

Only it did not manifest yet into a real problem for me, but so far, the small blisters seem to have levelled out again a bit after heating up the heat bed for the next print. Now, I usually use brims to help the stuff stick to the bed, which worked fine. But, yes, I did have the ABS come off a bit when not using brims and when printing larger things.

Maybe our PEI does not stick properly to the heat bed? Maybe too much air left below the sheet? In the 'Change The PEI Sheet' manual, the final sheet looks totally black, while I can see the heating wires on my heat bed. Like in your picture. Is that normal? Or is that a problem?

Re: Print Issues (with picture)

Same here. Anyone found a solution?

My prints used to stick like a charm (PLA) but now nothing sticks (even the Batman on the SD card) unless I go slooooooow.
I'm thinking of replacing my PEI sheet. But it's only 3 months old (11 days of printing according to the stats). How long is it supposed to last?

Re: Print Issues (with picture)

@ProsimKrmitVeprovym & alexis:
when you've found the optimal z-live adjustment level, the print should stick at the pei sheet like hell 😈 (even if it was already 3 month in use), especially when you clean the pei sheet regular with acetone or acetone based nail polish remover + ipa (ipa alone won't remove grease and fat from your fingerprints reliable).

💡 when you suddenly encounter problems with seemingly altering z-live adjustment values and nothing likes to stick at the bed, make sure the nozzle and the heatbreak both are sitting tight in the heater block when the hotend is at it's maximum temperature. furthermore: make sure that the whole hotend sits tight into the extruder body and that there is no temperature bridge of molten filament (maybe remainders from a clogged nozzle) between the heater block and extruder body.

➡ sometimes you may have some blisters at your pei sheet after a print with a large first layer surface and hot printbed -> these blisters vanish after some days and several heating cycles, so no need to be concerned.

Re: Print Issues (with picture)

I too had problems at first. I was using buildtek on my other printers and stuff sticks too well....

I messed and messed with z live adjustments, better not perfect.
I sanded the PEI sheet with 600 wet/dry sandpaper much better.
Tried glue stick stuff sticks well with that.

What I do now is clean the bed with the wipes and use a brim on most parts, cured the problem 100%

So if I was to buy another prusa I would sand then clean brim if needed.

side note this is all with pla.

Bob

Re: Print Issues (with picture)

To follow up, the print did actually finish and the only changes I made were lowering the z height slightly, raising the nozzle temp 5 degrees, and using the glue stick.

It seems all the problems I'm having are being caused by the heatbed. I read that every new layer of ABS likes to pull on the layer below it and tends to warp if not secured properly. I looked at the 2 failed prints and sure enough they base was warped because the heatbed did not them down. This makes sense because if the sides warp eventually the nozzle will hit the plastic on whichever layer it's currently at and the print gets knocked off the heatbed.

Now the question is why is this happening? One of the selling features of this printer is a "Hassle free PEI print surface" which I was told does not require a glue stick. What I noticed with the heatbed is that it tends to retain the outlines of previous prints. If I run my fingers on it, it does not feel perfectly smooth, and when I print something with a larger flat surface area, I can see imprints on the bottom of it from previous prints I have made. It made me realize this is most likely why it seems the prints are getting worse. When I assembled the printer initially, quickly tuned the z, and printed out the batman logo it came out great with no problems. Now with all the slight hills and valleys from all the prints I've made, new prints are having a harder time sticking to the PEI heatbed, so even if my Z height is great, it doesn't matter if the filament pulls off because it goes over a valley somewhere on the heatbed while on it's first layer.

I'd like to know if others have noticed the same thing happening after having used the printer for a while.

This has definitely rang a bell for me, I have noticed my prints get worse and harder to dial in. Question is, what to do about it?

Re: Print Issues (with picture)

Hi guys, I printed this castle for the first time at 70% speed on low power mode and the first half turned out fine. The top has a beading pattern and falls apart easily. What could be causing this?

Re: Print Issues (with picture)

Hi guys, I printed this castle for the first time at 70% speed on low power mode and the first half turned out fine. The top has a beading pattern and falls apart easily. What could be causing this?

I just got done solving this problem. It was hell. Anyways, your issue looks exactly like mine.

Do this test:

Move the extruder near where ot fails most often. Then run a long extrusion command like load filament. While it is extruding, move the cable harness around.

It your motor starts acting up, it's an issue with your extruder motor cable breaking. I had to solder together the cables where they were bending to fix the problem.