How do I get reliable prints?  

RE: How do I get reliable prints?

Hi Scot, 
important thigs are 
Good Mesh Bed levelling  (Stet to 7x7 mesh bed levelling using LCD Display (Settings>Mesh Bed) and choose 7x7   to test 49 points instead of 9 points on the Build Plate

Really Clean Build plate surface   
I use how water and dish detergent (Dawn, or Fairy Liquid )   rinse well with hot water and dry immediately with Paper towels, for PLA filament on PEI this should be all that you need in the way of surface preparation

then you need good Lize Z setting
I use the 'Life Adjust 'Z' My Way' Process in preference to the Prusa first layer tool... 
https://forum.prusa3d.com/forum/original-prusa-i3-mk3s-mk3-assembly-and-first-prints-troubleshooting/life-adjust-z-my-way/

these values are for My build plate, yours will probably be different,  but the small changes give a big difference in print quality

and 70C bed temp is good for PLA on PEI

RE: How do I get reliable prints?

Posted by: @scottblanc

I have spent a ton of time calibrating my i3 MK3S but am not finding a way to produce reliable prints. My print success rate is about 10%. Take this print I just tried where it started out fine and then half way through it just went haywire. Any ideas what the problem might be?

Joan said it beds, but:

Really Clean That Build plate Surface:  If it is not clean, it will not stick.  I use dawn and non-scratch scrubber.  Dry it completely before you put it on the bed and do not touch it with your dirty hands.  

Make sure your Live Z or Z offset is right:  I have to use the 'Life Adjust 'Z' My Way' Process also and it works.  You do not have this tuned in you will not get a good first layer.  

Once you do your Z calibration, post a picture of it here.  

RE: How do I get reliable prints?

I just can repeat what has already been said: You need a got first layer adhesion.

Here some hints from what I have already learned:

• Your example has a quite small area on the first layer. This is then critical in case adhesion is an issue. You may have more success if adding a brim or a very wide (10mm) near skirt (0.7mm).
• Prusa default setting normally are already at quite high temperatures. I do not know about your filament, but increasing the bed temperature could help to increase adhesion.
• Warping shouldn't be an issue for PLA, but it will be if your printer is not protected against flow, especially if the room is colder.
• I often have trouble when changing the filament. It seems that there is some detergents sticking on the bed for a longer time. I avoid changing frequently. I now take advantage of the Prusa magnetic solution using different bed for different filaments.

Hope it helps.