A Newbie Who Is Totally Lost  

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zac.w
(@zac-w)
Active Member

Hello all,

So this is my first attempt at 3D printing. As far as I can tell everything is put together correctly - I get no error messages or the like. Im up to the manual Z Height calibration, and I've been lost for a week. Keep in mind I do not know terms or phrases very well with regards to 3D printing. I have read through the forums, watched YouTube videos, and more. I've tried heights from .3 to 1.3. Above 1.2 seems to be best - the initial 3 lines it does look good. Then the PLA starts to curl up to the nozzle and its all downhill from there. Id love to be able to pick some of you veterans' brains about this - I've been involved in CAD for years and would love to be able to print stuff at home instead of the cost and long wait times of Shapeways or similar services.

Im running standard PLA temps (I've seen some people recommend running more like 230/60 instead of the default 215/60, but I don't even know how to go about changing that). My board is clean. I believe I have the standard board not the fancier one - they were sold out of the higher end one when I bought my kit. I also have a spool of PETG I could try to test things with, but since the printer is asking for PLA for calibrations and testing I haven't touched it.

Please help

~Zac

Best Answer by 3Delight:

My pennies worth...

  • Make sure your PINDA probe is the right amount higher relative to the tip of the nozzle the tip of the nozzle.
  • Make sure the temperature set either in PrusaSlicer or on the LCD menu system is right for the PLA you are using.
  • Do the self test.
  • Do the calibration routine, and get the Live Z height right.
  • Try printing the Prusa logo plate and watch the first layer carefully.

Issues...

  • If the filament is curling up as it comes out the nozzle it can be because the side that it is curling towards is cooling quicker than the rest causing it to bend upwards.  This often occurs when extruding filament with the extruder raised up high and the part fan on.  Just use the pliers supplied to pull it away.  If it is leaking out of the nozzle constantly even when not printing this can mean that the hotend temperature is too high.
  • If it's curling up while printing the the likeliest cause is the Live Z is to high and there is too big a gap between the bed/last layer allowing the filament to curl up before it is laid down.
  • If the filament is not sticking to the smooth sheet, 9 times out of ten it is down to either a dirty bed or to higher Live Z.

Notes...

  • To make the gap bigger between nozzle and bed/previous layers REDUCE the Z value (Eg. from 0.715 to 0.689)
  • To make the gap smaller increase the Z value (Eg. from 0.715 to 0.765)
  • The PINDA probe should be about 0.8mm to 1.0mm higher than the nozzle tip.
  • Clean the bed with detergent and water, and dry it with a lint free cloth.  Use the rough side of a washing up sponge to gently scrub it.

Suggestions...

  • Post a photo of the front view of the extruder/nozzle after homing the printer so we can see the position of your nozzle and PINDA.
  • Post a picture of a failed print.
  • Post a video of the filament starting to curl.

 

Posted : 15/08/2020 8:14 am
Neophyl
(@neophyl)
Noble Member

Hi and welcome to the forum.  From your description of your printing surface it sounds like you have the smooth sheet.  That is actually way better for printing PLA than the textured in general.  Its less picky and its easier to judge your first layer with.  Both sheet types use a PEI surface, the smooth is a sticker that is applied using I think 3m adhesive and the textured is a powder coated application onto the thin steel sheet.

There are better and easier methods to dial in the correct z height offset, and as getting that correct and absolute bed cleanliness are the 2 most important factors to getting successful prints then its best to learn that method.

This thread https://forum.prusaprinters.org/forum/original-prusa-i3-mk3s-mk3-assembly-and-first-prints-troubleshooting/life-adjust-z-my-way/   details the process and has some ready to go gcode you can use.  However its pretty simple in essence.  You print a 75x75mm square that is 1 layer thick (0.2mm).  As its printing you adjust the z height and as the lines are next to each other you can see them start to merge together as they print and eventually you get no gaps between them.  If you start getting rougher 'wave' like patterns it means you have gone too close and the nozzle is pushing material in front of itself.  When you have it perfect you should be able to remove the little square and tug on it without the strands separating, leaving a thin square of solid plastic.

It usually takes a couple of goes initially but you can very quickly get the hang of it.

Also on the subject of bed cleanliness imo the absolute best method is plain old dish soap (fairy/dawn or equivalent) and LOTS of HOT water.  IPA generally thins skin oils around and spreads them in a thin film.  You need to use a lot of it to completely de-grease a surface.  Dish soap on the other hand is designed to remove grease.  Rinse it off with lots of hot water and then don't touch the surface afterwards with your fingers.  Handle by the edges.  You can get fantastic adhesion.  As an example my favourite picture 🙂

Posted : 15/08/2020 8:47 am
stev-19 liked
zac.w
(@zac-w)
Active Member

@neophyl

Yea, I’ve seen people doing that. It’s 3am as of posting this and I’m up for work at 7, so I decided to shelve it for the night. I’ll definitely try that method though

Posted : 15/08/2020 8:52 am
GkMakeIt
(@gkmakeit)
Estimable Member

Have you tried this?

https://www.prusaprinters.org/prints/20306-first-layer-calibration

Posted : 15/08/2020 3:33 pm
zac.w
(@zac-w)
Active Member

@gkmakeit

That’s pretty much what @neophyl said to do. It’s on my list for this afternoon. 

Posted : 15/08/2020 3:36 pm
zac.w
(@zac-w)
Active Member

Alright, so I attempted to do that square test print. However, I still cant get PLA to stick to my sheet. It gets through the first four corners, but when it goes to start an inner fill square it just brings the whole thing with it. Thoughts? Just before I tried I thoroughly washed it with soap and water and dried it, and never touched the face of the sheet. 

This post was modified 1 month ago by zac.w
Posted : 15/08/2020 11:02 pm
GkMakeIt
(@gkmakeit)
Estimable Member

@zac-w

How about some photos to show us what the aftermath looks like? You know what they say, pictures worth a thousand words.

Posted : 16/08/2020 1:20 am
3Delight
(@3delight)
Moderator Moderator

My pennies worth...

  • Make sure your PINDA probe is the right amount higher relative to the tip of the nozzle the tip of the nozzle.
  • Make sure the temperature set either in PrusaSlicer or on the LCD menu system is right for the PLA you are using.
  • Do the self test.
  • Do the calibration routine, and get the Live Z height right.
  • Try printing the Prusa logo plate and watch the first layer carefully.

Issues...

  • If the filament is curling up as it comes out the nozzle it can be because the side that it is curling towards is cooling quicker than the rest causing it to bend upwards.  This often occurs when extruding filament with the extruder raised up high and the part fan on.  Just use the pliers supplied to pull it away.  If it is leaking out of the nozzle constantly even when not printing this can mean that the hotend temperature is too high.
  • If it's curling up while printing the the likeliest cause is the Live Z is to high and there is too big a gap between the bed/last layer allowing the filament to curl up before it is laid down.
  • If the filament is not sticking to the smooth sheet, 9 times out of ten it is down to either a dirty bed or to higher Live Z.

Notes...

  • To make the gap bigger between nozzle and bed/previous layers REDUCE the Z value (Eg. from 0.715 to 0.689)
  • To make the gap smaller increase the Z value (Eg. from 0.715 to 0.765)
  • The PINDA probe should be about 0.8mm to 1.0mm higher than the nozzle tip.
  • Clean the bed with detergent and water, and dry it with a lint free cloth.  Use the rough side of a washing up sponge to gently scrub it.

Suggestions...

  • Post a photo of the front view of the extruder/nozzle after homing the printer so we can see the position of your nozzle and PINDA.
  • Post a picture of a failed print.
  • Post a video of the filament starting to curl.

 

Posted : 16/08/2020 1:50 am
zac.w
(@zac-w)
Active Member

@gkmakeit

Pics were basically pointless. Imagine a blob of PLA strings.

@3delight

Since my last reply I actually was checking minute details and noted my PINDA looked a bit low. So I reset it and that actually made me be able to attempt to print. Ive just about narrowed down the Z-height now. I assume in the few months since I built this thing it sagged a bit or something.

 

Thanks everyone for the help, Ill try the 75x75 square next just to confirm; if I dont reply on here assume its all good now.

Posted : 16/08/2020 2:02 am
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