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  1. #11
    Super Moderator curious aardvark's Avatar
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    petg can be tricky.
    It also sounds like your bed is not level or the print head gantry is not level.

    Welcome to the wondeful world of ender printers.

    I've done relatively few pet-g prints, and those always on Printbite - so that doesn't help you much.

    A print adhesive might help. Magigoo is pretty good - I think dimafix is better - but not sure if that's still available.
    But I have no idea if either are good for pet-g.

    What might be a better option would be a hi-temp pla.
    Either one that you 'cure' in a 'cool' oven or the more expensive variety that doesn't need curing.
    Both can hit a glass point of 100c or higher.

    And if that's still not hot enough - stop living on mercury ;-)

    Also if you use a non-heat-absorbent colour like white - I still don't see how a print can exceed 65c outdoors.
    Glass points for abs and pet-g aren't that much higher either - I think abs is around 75 and pet-g 75-80 (I'm not using silly fahrenheits. any temperature system where 0 is a bucket of ice and salt and 100 is the inventors wife's armpit - is a bit arbitrary for my liking ;-) )


    From a weather point of view - sometimes we have way too much.
    For the last week it's been hots and dry - today, temp dropped by about 15c and it's been raining all day.
    Great for the garden - but not brilliant if you're camping.
    The one thing we lack in our weather in england is predictability.
    Weather forecasts are getting better - but anything much over a couple of days is always going to be suspect. And people tend to plan things further ahead than that.

    That said I've got friends in california where weather is TOO predictable :-)

    I suspect that no matter where you drop a human, in a few months they'll always complain about the weather ;-)
    Last edited by curious aardvark; 08-16-2020 at 08:01 AM.

  2. #12
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    Hi This thread started about ABS of which I have a little knowledge. Perhaps I can help, despite a student profile definition I am a scientist and development engineer of more than 50 years experience and back at the beginning of lockdown was asked by the scientific consultancy I am a member of to look into bring 3d printing in house to reduce the disruption caused by the delays of sending out 3d prints to a bureau. As a result we purchased a basic machine(a ender 3pro-sorry curious Aardvark)p and set up and controlled experiment as to what we could do with it. We wanted to be able to print in ABS and Nylon routinely.

    As part of that we tried a very large number or build plate materials and adhesion aids - bat thats another story!! we also bought a range ABS filaments to try ( I know that is only possible when you have a company cheque book !) . In the case of ABS filaments we tried 3 filaments with a couple os standard models that we already had had made by SLS in nylon. We found that with a model with an area in contact with the bed plate of 53 x 53 mm and sharpish corners we had reliable printing with only one of the materials which was 3dfiloprints ABS X and that the reliable ( almost 100% success) with either Enders accessory Glass plate with printed on texture or Fufnol Whale Grade SRBF sheet sanded with 220 to remove the shiny surface both best with a thin layer of ABS juice.

    print Settings

    layer Ht 0.3 initial
    Layer body 0.2
    Build Temp 245
    initial Temp 250
    Build Plate 80
    These temps used building onto a 1mm Tufnol Sheet clamped to the Creality glass bed (plain side)

    Fan ON

    Speed printing 70mm/s
    initial 35mm/s
    we use a skirt to start the extruder and work in a perspex enclosure with no additional Heating.

    I hope that helps.

  3. #13
    abs separate in UV, or so they state.. you should take a gander at PETG for this part on the off chance that it is just warmth/sun that is driving no PLA. The part looks straightforward without a great deal of little projections. PETG would be great, I use it for outside camera mounts. No walled in area, not distorting yet not an edge as ABS but rather entirely tough curves a great deal before it breaks.

  4. #14
    Thank you Gambo for the detailed reply.

    I'll give it a try once my printer is functional once again!A while ago, I took apart the printer due to a jam, and periodic mis-printing.


    The epoxy/ceramic around the nozzle, and the Teflon wrap was chipped away and no longer part of the print head.When removing the nylon tube, I didn't take note of the depth within the print head.


    Now I'm noticing the PLA gets jammed as shown in the image below, almost all of the time. The distance of thetube between the nozzle has been adjusted between a 1/4" and completely touching.


    The bed to nozzle adjustmentis one sheet of paper at all four corners (checked twice). Also used feeler gauges. I've tried a higher bed to nozzle calibration thinking it was too tight.For whatever reason, the filament jams itself almost instantly, however when pre-heating the nozzle & bed, I can handfeed the PLA through the entire assembly and it exits with ease.


    Where do I begin troubleshooting? Is the printer no longer able to print without the white epoxy and Teflon wrap (heat sink)?
    Attached Images Attached Images

  5. #15
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    The tube which incidentally is made of PTFE tube should go right to the bottom of the heat sink, you may have to push it a bit further through the screw fitting at the top. being short will not help filament flow.

  6. #16
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    Bed calibration is not likely to cause your problem! I don't know how thick you paper is but the paper I use is 0.08mm of 0.003" in old money. The normal slicer setting raises the nozzle 0.3mm for the first layer so there should be plenty of room for the plastic to flow.

    one thing I have found is that if the nozzle is much further away from the bed than that first layer adhesion is poor or none at all. I level in the normal way with a sheet of paper but check the ht of the nozzle over the bed with feelers gauge made of 0.002" and 0.003" ie 0.05 and 0.08mm steel shim stock. If the ht of the nozzle at the point of printing is outside these limits I adjust the whole bed up or down to correct.

  7. #17
    Super Moderator curious aardvark's Avatar
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    to make abs worth printing - and personally I don't think it's worth the hassle. you need to reduce how each layer cools.
    So even an 'unheated' (rather, not temperature controlled as it's heated by the : bed, print head and any other parts that get warm during use) perspex enclosure will help tremendously by keeping the entire print at the same temperature and avoiding each layer cooling and shrinking seperately.

    Actually printing abs is pretty easy - my first 6 months printing | used nothing else but abs on a non-enclosed machine.
    I swore a lot more and was never really happy with the prints - but by using a raft I never had any adhesion issues.
    Often there were issues removing the raft from the base of the print - the longer the print the harder it is to do.

    Once I discovered that everything I'd read online about pla was pretty much 100% wrong. I never touched abs again. No more stink in my workshop - no more rafts and crappy prints. Stronger better looking prints and when I added the sheet of Printbite - no more glue or adhesion hassle :-)
    At that point printing became a joy rather than a chore.
    And the printers began to 'breed' (currently have 6)

    When you consider that abs stinks. shrinks, is not great for anything that will be in direct sunlight and really is not well suited to 3d printing, then pla and pet-g are usually much better choices.
    And there are so many other specialist filaments around that you can pretty much tailor the filament you use to any specific task.

    But if you are going to persist in using abs - then keeping the model at a constant temperature as close to the build plate temp as possible and cooling the entire part at the same time, so that shrinkage is consistent across all layers, is pretty crucial.

    @Gambo - odd choice of printer lol
    But thanks for the information - any actual hard information and methodical approach, is always welcome :-)

  8. #18
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    Thank You Aardvark.
    Actually the choice of the printer was very deliberate. for our experiments we wanted a very simple machine and I had seen several used by an acquaintance in his business and they seemed to be just the job and not badly made. Actually I got suckered by an internet seller who actually sold me a knock off of the Creality Ender 3pro. Apparently a CTC A13 or thats what it was labeled. It was the worst piece of junk I have seen in a long time if I had been I hobbyist I think I would have give up there and then. I still have the junk in the corner of my Lab as a reminder to always read Internet ads very carefully. I the event when we got the Creality Ender 3pro we have been using every day since the beginning of March with no problems.

    As to Using ABS I agree that ABS can be a difficult material to print but for one of our requirements we needed the material to be resistant to dilute metal solutions but at pH13 when we tested PLA it delaminated between layers before our eyes. We also tried Poly Acetal which worked fine. Even so we decided to go with ABS but we use the low warp ABS product ABS-X from Mitsubishi Chemicals in Holland sold under several companies own brands we get ours from 3dfiloprint. Using that material we have made dozens of parts without failure using the settings above.
    I hope this helps someone.

  9. #19
    Super Moderator curious aardvark's Avatar
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    have you tried pet-g ?
    Not sure about alkalines but it's resistant to most chemicals. Also prints much easier than abs - almost no layer shrinkage and does not stink the room up :-)

    Yeah - the chinese will even rip off each other :-)
    And yep the crealuity machuines I've seen in the 'flesh' - as it were - have looked like solid well made machines. I just wish, they'd gone with the original i3 design. You only have to look round here at all the 'I have an ender 3 with problems' threads, to see why that would have been such a good idea.

    Yes they work - but they could have worked great, printed 3x faster and had significantly fewer issues.
    I saw a youtube video recently with the title: 'the first 24 modifications I made to my ender 3'.
    Crazy.
    This is not normal.
    I think I've added half a dozen mods to my delta including print area cooling fan duct - the replicator clones just ptfe tubing in the hotends and extruders and cooling fan.
    Nothing at all to my mini delta.
    My ctc - cheapest i3 on the planet - that's had a few - but still nowhere near double figures.
    And the sapphire pro corexy - that'll probably end up with just the one - moving the extruder so it's a near direct drive - rather than a bowden.

    The point is that a decently designed 3d printer - no matter how cheap - should not need dozens of modifications to just make it work at an acceptable level.

    But, I'd be interested to know if pet-g is alkaline resistant.

  10. #20
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    No I have not tried PET-G yet though I will at some stage. unfortunately PET-G is attacked by strong alkaline solutions so it is not usable for the current project. The best material for our purpose would be Poly Acetal ( Delrin POM ) but at the moment supplies of Poly Acetal filament are rather limited and the one we could get hold of was far too variable for our use once supply returns to normal we will have another go at it. Mean while we seem to have "dialed in" ABS and Poly amide so we will be using those for a while. On of our other on going project involved strong organic solvents hence the Nylon.

    I have seen all the cries for help with ender 3s I wonder how many of them think they have the Genuine Creality Ender 3 but have a second rate knock off.

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