[Résolu] Difficulting printing in Sainsmart PRO PETG  

RE: Difficulting printing in Sainsmart PRO PETG

here's the .zip with the .3mf file and the two .stl files I got from thingiverse

RE: Difficulting printing in Sainsmart PRO PETG

The first layer looks great and adhesion is totally fine.

RE: Difficulting printing in Sainsmart PRO PETG

I haven't looked at your .3MF yet but your first layer is definitely high you should consider lowering your live Z.

RE: Difficulting printing in Sainsmart PRO PETG

@swiss_cheese

during the course of the day I've had this all the way down to 0.0 and stepping up to -0.005, -.010, etc   I've also upped the extrusion multiplier to 1.2 in order to get the perimeters and first layer lines to lay down together.  I just need a fresh set of eyes on my config lol.  I have printed with this stuff before, but with the clears,  this one, the taulman3d and a sunlu clear, I've never had great success with the first layer being nice and tight.

RE: Difficulting printing in Sainsmart PRO PETG

Ok, your .3mf is kinda a mess, I'm going to suggest you select a default generic PETG profile and not change everything, just as an example of what I'm referring to you are using a 0.4 nozzle with a 0.8 everything and a 0.1 layer height this is going to clog the hell out of your nozzle, and your images show that. the profiles are pretty clean and well rounded as they come from the factory and I think you should try using them as is with maybe a temperature adjustment for the PETG your using. it looks like you went hog wild with this profile.

RE: Difficulting printing in Sainsmart PRO PETG

@swiss_cheese

Yes, I've been tinkering with it all day.  Sometimes it's easy to get off into the weeds.  Printing another project for my wife in PLA at the moment, I need some success, and I'll will try to go back to the generic profile again. 

Thanks!, I'll let you know how it goes.  probably tomorrow.

RE: Difficulting printing in Sainsmart PRO PETG

your welcome and good luck

RE: Difficulting printing in Sainsmart PRO PETG

@swiss_cheese

alright, I stopped that one, it had just gotten started and wasn't even on the infill of the first layer.   I just loaded from the default profiles, so going to give this a shot.

Thanks!

RE: Difficulting printing in Sainsmart PRO PETG

Lol so far adhesion issues right off the bat.  part of the reason I changed the first layer to be so high.   would setting .3mm layer height for first layer and .1mm for rest be ok?  That thicker first layer + glue seems to work on my pei sheet pretty well.

RE: Difficulting printing in Sainsmart PRO PETG

clean the sheet, very well, reduce your live Z it's to high from the images you shown. then since your using smooth PEI add a squirt of original Windex if avalable, just wipe it on then off just like cleaning a window. if your Z s correct you should have great adhesion. 

RE: Difficulting printing in Sainsmart PRO PETG

Ok after a very frustrating day.  I'm still not really any closer.

Here's updated .3mf zip.

I could NOT get a good adhesion with windex.  it almost did, but some of the first layer perimeters simply dragged. I played with various zOffsets.  the only way I could get any stick on the first layer was to set it to be .3 height and .8mm width(first layer only).   I also ended up going back to tape + glue after several scrubs of the plate and windex applications.  With the tape and a -.043 zOffset it started to look good but as it started to print the start of that curved bottom you could start hearing what sounded like the nozzle hitting the perimeter when it jumped from pot to lid and back.  I'll attach pictures of where it starts to hit and where I stop the print.   I'll meditate on this some tomorrow.  

RE: Difficulting printing in Sainsmart PRO PETG

First layer, which I know seems too high, but even then the nozzle seems to bump against the model.

RE: Difficulting printing in Sainsmart PRO PETG

And here's the point at which I start hearing what sounds like the nozzle hitting the print.

The only type of adhesion I've not tried is hairspray.  The settings were reverted back to the generic profiles that come with prusaslicer and only slight changes made.  

first layer .8mm
100% infill
240 on the nozzle temp

I'm spent.  I'll try to dig into this some more tomorrow, but a second set of experienced eyes would be appreciated to see what I'm missing.

Thanks!

RE: Difficulting printing in Sainsmart PRO PETG

I hate to admit it, but I think I was missing a fundamental understanding of the zOffset!  lol   I feel silly, but I was misunderstanding the negative nature.   I discovered this when folks were saying you're zOffset is too high.  I tried another filament I had just used today to print a part.  That failed on this model too.  That got me looking really closely at things.  Long story short, I discovered that -0.142 is what I should have been using instead of -0.043 lol 

I'm going to try to do a print of this with this new found knowledge.  I'll let you all know how it goes!

RE: Difficulting printing in Sainsmart PRO PETG

Did some more tuning in the other filament, Paramount3D PETG, and at .2mm layer height my zOffset ended up being -0.172.

Currently printing the makeup pot in this filament at 0.2mm layer height and it's printing beautifully.   After this I'm going to switch to the sainsmart again and figure out the zOffset for a .1mm layer height and try this again.  This has been a very instructive process.  I find these failures are the best teacher and I appreciate folks time in this!

RE: Difficulting printing in Sainsmart PRO PETG

Posted by: @ssill2

I hate to admit it, but I think I was missing a fundamental understanding of the zOffset! 

That's the main reason I emphasize the importance of Live-Z calibration and PEI cleaning before even remotely suggesting adding any sort of goop to "improve bed adhesion". If you don't get the basics right, you're going to have ongoing problems. I have no idea why this triggers puerile responses from some folks claiming persecution of their favorite goop, but you really need to get the basics right. Then you can try enhancers.

lol   I feel silly, but I was misunderstanding the negative nature.   I discovered this when folks were saying you're zOffset is too high.  I tried another filament I had just used today to print a part.  That failed on this model too.  That got me looking really closely at things.  Long story short, I discovered that -0.142 is what I should have been using instead of -0.043 lol 

Not your fault. If you search around on the Internet, it's easy to get even more confused. On many printers, you raise the bed to reduce the 1st layer gap. On the Prusa, you lower the nozzle towards the bed. I try to remember to always say "lower the nozzle (make Live-Z more negative).

I'm going to try to do a print of this with this new found knowledge.  I'll let you all know how it goes!

The 75x75x0.2mm square from Jeff Jordan's "Life Adjust" procedure is an effective and quick way to judge your 1st layer results. Good luck with it. This is definitely a hobby that will keep you learning things.

RE: Difficulting printing in Sainsmart PRO PETG

@bobstro

yeah.  I'm a software developer and this epiphany is akin to the first time you understand pointers in C lol.   It changes the whole ballgame!

Of course with this knowledge,  I get the attached.  Flawless lol.

I created a 1 layer .2mm tall model similar to the one you mentioned.   This afternoon I'm going to do the same for .1mm and figure out the zOffset for that layer height and this filament.  I feel like a whole new world just opened up for me lol.

Thanks! 

RE: Difficulting printing in Sainsmart PRO PETG

It's as though I never said anything at all, am I even here? 🤔 

RE: Difficulting printing in Sainsmart PRO PETG

@swiss_cheese

You ARE! 🙂  I appreciate you looking at this problem.  with .2mm layer height working I'm now trying .1mm.  I've figured out my zOffset using the live z to be -0.370 or so.   I also slowed down my print speed slightly.  currently trying the same model above.  I started getting artifacts after what looked like a pretty good start.  If I can get the .1mm working in this green paramount3d petg, I'll switch back to the sainsmart petg and do the whole zOffset thing for that one too.