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3D Printer General Chat

Discussion in 'Hobby Engineering' started by Spanos, May 26, 2021.

  1. Spanos

    Spanos Member

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    Recently bought myself a second hand creator pro and just been printing benchmarks and little doodads to improve the printer. I've been trying to learn how to 3D print, and pretty much the only thing I've learned is that each print seems to require different settings!

    I'd been struggling a little with the first layer adhesion on PLA. I adopted what seems to be everyone's recommendations for first layer settings but wasn't having great success. First layer thickness was 0.4 mm to match nozzle width and an extrusion multiplier of 150%. This wasn't working, so I stuffed around a bit until I changed the thickness to 0.2 mm and all was well in the world again. I think there was just too much filament coming out and was ending up smooshing the extrusion against itself.

    Anyway, figured a general chat would be good instead of thread crapping the other 3d print threads.
     
  2. tumutbound

    tumutbound Member

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    Different filaments need different settings, even different colours of the same filament brand might need different settings. Welcome to the wonderful world of 3D printing !
    There are a couple of good Youtube channels to check out for this sort of thing. Teaching Tech and CHEP are both worth a look. If there's a forum for the Creator Pro, check it out also, they will have found what works.
     
    m3k likes this.
  3. SCorpion2

    SCorpion2 Member

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    True. To be honest, I probably should have trusted my eyes in this case. The printer was putting down rows of filament which would pull the adjacent layers up. I knew I should have adjusted the layer thickness. haha. live and learn.

    I just printed half a soap travelling container. I did the top half and used a big 8 mm fillet for the external corners. This introduced a big bridge, which it handled ok but looks a bit crappy. See below 20210526_211014[1].jpg

    The next half has the same external fillet, but this time, I put a 30 degree chamfer in and then filleted the chamfer. Think it should work a lot better.

    I'm actually having just lots of fun tinkering and learning at the moment. I have plans to make spare car trim in the future, but I need to just keep making these sort of things to get gud.
     
  4. m3k

    m3k Member

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    yea fillets are really ugly on underside- i often just chamfer undersides

    for pla stiction-

    clean clean clean bed- With isopropyl- and make sure your first layer is very flat and even

    sometimes if stiction is too great using a gluestick (pva) and smearing it around with a damp rag is awesome for getting it to have just the right amount of stiction

    obviously heating the bed between 40-60c is good if it wont stick then increase temp- but be aware it can cause elephant foot the hotter you go. you can always counteract it with adding a chamfer to the bottom of your designs

    -mesh bed leveling is pretty-much required for most beds that arnt glass or high end milled tooling plates- because as beds heat up they tend to release internal stressors unevenly and can lose flatness, especially on larger printers.

    so yeah there's alot to think about and learn about. but its a great hobby/empowering tool. and i really think there should be one in every home where somebody is capable to use CAD because.... the amount of things that you can print - probably even considering all the plastic you waste- has a net positive on the environment-.. TECHNICALLY PLA is derived from corn which makes it carbon neutral even if you dump it in landfill?? LOL i mean assuming production and shipping doesn't add alot of co2 :S :p but yeah

    i really love how manufacturers are posting 3d printable fixes and mods to their products instead of tooling up ABS injection molding and potentially adding to pollution shipping all these parts individually when you can buy locally sourced plastic and just download and print on demand with theoretically carbon neutral plastic LOL i mean there's a lot of holes to be poked in that utopia concept but i mean its heartwarming none the less.

    back to stiction

    u dont want to go too large with layer height
    the best ive found is 0.2mm first layer with MAYBE 150% extrusion width if ur having issues, on a 0.4 nozle i like generally making the extrusion with 0.45 anyway it tends to make prints smoother and stronger, simplify 3d automatically rounds up to 0.47 actually. and its... quite nice....

    but yeah its really about getting the bed hot enough to keep the plastic a bit tacky and when it cools down it makes releasing the part easier.

    and getting your first layer height to be accurate can be hard- there are alot of ways to do it but in my opinion the best is enabling babystepping in your firmware and dialing it in by eye
     
    Last edited: May 26, 2021
  5. SCorpion2

    SCorpion2 Member

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    I'll have to try the damp rag and gluestick option one day. I often use glue stick but the print is almost always jammed on the plate. I watch others remove their prints and they just grab them and yank them off. I have to pry every print off with a paint scraper. haha. If the bed is cool, no chance of removing the print at all.

    I'm going to look at changing beds some stage in the future to something that suits filaments that I can use in/on the car. Initially was thinking glass, but I should probably think about what filaments I am actually going to use and then decide. What does everyone use in cars these days? I'll have to see how level my bed actually is now, I've never printed a test. I don't think its warped as my first layer is always good now with the reduced height but it'll be worth finding out anyway. I got some white PLA with the printer that I've been tearing through. It was contaminated I think as benchies I was printing had layers of brown through it. haha.

    I've found 0.2 mm first layer works great. I've made the extrusion width a bit wider at 0.6 mm. it looks able to provide the best inter-layer strength going by other peoples tests and things. I wish I could babystep on the creator pro, would have had much less failures while i was learning. It was easy to see that I needed to adjust the height of the bed. I've made up a bracket for a dial guage to use to level the bed instead of the old piece of paper method. Havent tried it yet as I havent bought a digital dial gauge yet.
     
  6. tumutbound

    tumutbound Member

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    I print on 4mm glass using hair spray, not glue.
    Prints stick very well and will self release when the bed cools down.
    This is with PLA but I have used glass with kapton tape for ABS.
     
  7. SCorpion2

    SCorpion2 Member

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    I'm leaning towards glass at this stage too. not sure what it'll be like with flexible filaments or nylon though.
     
  8. tumutbound

    tumutbound Member

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    It's OK with TPU, standard hotend doesn't handle nylon but once the direct dirve extruder and E3D hotned fitted, I'll give it a try.
     
  9. m3k

    m3k Member

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    the black diamond coating stuff on glass is legit.
     
  10. SCorpion2

    SCorpion2 Member

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    Yeah, I have to do the same upgrades too. The upgrades imprinting at the moment are to get the enclosure a bit more air tight to keep the heat in.

    I've seen that. Everyone seems to just grab perfect prints off without wrestling with it like I do!
     
  11. Butcher9_9

    Butcher9_9 Member

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    Glass works well for PLA with no glue (or at least ceramic coated side of mine does). 60C
    PETG you have to use a very light but consistent coat of the glue stick (I use the damp tag trick on the non coated side) , PETG bonds too well to glass and will rip parts out otherwise. 80C
    For ABS I use ticker layer of Glue stick (Non coasted glass side). 100-110C

    For overhanging fillets and chamfers the thinner layers are generally better down to about 0.12 (after which heat from makes things worse). Thinner layers means a smaller % of that layer is overhanging for a given angle (IE a 45% angle with a 0.4 width and 0.4 layer would have no support for each layer while a 0.2 layer would have 50% support and a 0.1 would have 75%. )

    For layers stick to less than 80% of the nozzle diameter, 50-60% is best normally.
     
  12. garfield2k

    garfield2k Member

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    ive had better results with pei sheet on spring steel. bought from alie with a smooth side and textured side. so far has been much better with pla, petg and abs. but definitely dial in you bed temps as other have suggested.
     
  13. SCorpion2

    SCorpion2 Member

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    So, I've set my path width setting to be 150% of the nozzle diameter and I think it's ruining my surface. 20210529_150618[1].jpg

    There is a whole bunch of 'zits' on the surface which only showed up after I changed the path width setting. Also, you can see just above the chamfer/fillet (the photo has rotated 90 degrees), that the print is a little wider near the chamfer/fillet than the rest of the straight wall.

    So I did some googling and found the following link. How to Get the Perfect Line Width Settings in 3D Printing - 3D Printerly. It looks like some software lets you set path width for different parts of the print like the wall, infill, top/bottom etc. Now I reckon I'm starting to get to the limits of what FlashPrint can do so now I'm looking at improving the slicer software. Whats everyone using? Simplify3D?

    I also probably need to change path width with layer height rather than just sticking with a set value.

    Also tried a bed levelling test. haha.

    20210529_113455[1].jpg
    this is after levelling the bed a few times. The old paper under the nozzle really isn't cutting it so I've just splurged and bought a dial gauge and vernier caliper so now I can start calibrating and levelling this printer properly. There is probably some bed warp which I'll have to check for once this current print is finished.
     
  14. apsilon

    apsilon Member

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    Being new to 3D printing myself one tip I picked up was to level the bed with it heated to your normal print temperature as it will be different compared to when it's at ambient.
     
  15. SCorpion2

    SCorpion2 Member

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    Thats a great tip. I'll have to see if it is warped at temp too.
     
  16. mrbean_phillip

    mrbean_phillip Member

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    Yep, agreed on the hairspray for PLA, I have a small Prusa here with an original PEI bed, but prints don’t stick well, a squirt of my wife’s Tresemmé spray works every time though ;)
     
  17. Butcher9_9

    Butcher9_9 Member

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    I would personally stick with 10-15% extra max. (I use 0.44mm on a 0.4mm nozzel)

    The mention of 150% in earlier posts was extrusion amount and that was only for the first layer.
     
  18. m3k

    m3k Member

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    yea i go from 0.4 to 0.48
     
  19. OP
    OP
    Spanos

    Spanos Member

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    I've dialled it back to nozzle width + layer height. Its working really well.

    I also pulled the extrusion multiplier from 109% back down to 90%, but now the top layers have holes in it. I'm working my way back up and i'm guessing it'll probably end up around 100% I'd say.

    I've reduced the print speed for the external surfaces from 50 mm/s to 12.5 mm/s too. This completely eliminated the ringing that was happening but introduced a bunch of zits that extend for about 20 mm from the start of the layer. My next attempt is to increase the print speed and dial in the retraction speed and distance. It was on 1.5 mm retraction and 30 mm/s retraction speed. The surfaces will be as perfect as they can possible be once i've got the print speed and retraction settings sorted. I've never had stringing or oozing so I've never had to play with the retraction.

    I'm definitely pushing up against the limits of Flashprint now. I'm thinking of buying Simplify3D. Anyone recommend anything different?

    Next thing I have to dial in is the dimensional accuracy and that should be about all I can do with PLA. Then i get to start all over again with different filaments!
     
  20. tumutbound

    tumutbound Member

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    For a slicer, have you tried Cura or PrusaSlicer?
    I use Cura at the moment because I have it dialled in for the job I'm currently doing but slowly migrating to PrusaSlicer.
     

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