3D Printer General Chat

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

  1. OP
    OP
    Spanos

    Spanos Member

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    Well, it now has 3 discrete layer shifts in this print. its still good, its still good!

    I don't think it is the heads crashing into the print or anything that is loose. The shifts are occuring almost in a pattern, but not quite, so I think the pattern might be a red herring. I suspect it must be a broken wire somewhere. 20210906_082454.jpg
     
  2. apsilon

    apsilon Member

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    Hoping someone can explain something for me. I have the smooth and textured sheets for my Prusa and really love the textured finish that sheet provides so bought myself the recently released satin version as well. Obviously need to set up the live Z for it so measured it with calipers simply to get a starting point. Found it was 0.06mm thinner than the textured sheet so figured the Z value for the textured sheet would be a good starting point and just go down a touch from there but right away I was getting rippling on the top surface which I believe is an indication of being too low. Came back up and settled on a value 0.02mm higher than the textured sheet that looks good. I'm a bit stumped as to why a value 0.02mm higher for a sheet that's 0.06 thinner appears right and the same value as the thicker sheet produces ripples?
     
  3. theSeekerr

    theSeekerr Member

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    Note that you're talking about a total difference of less than 0.1mm here, so you don't need a BIG effect to explain what you're seeing.

    In this case I think it's as simple as "the low parts of the rough textured surface are more than 0.1mm deep so you need a good amount of additional smoosh to get in there and achieve good adhesion"
     
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  4. apsilon

    apsilon Member

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    That seems entirely plausible. I'm focusing too much on the overall thickness of sheet as measured but as you say this only takes into account the high points of the texture and not the lows.
     
  5. CQGLHyperion

    CQGLHyperion Member

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    A lot of the time the Z offset can be backwards as well.
     
  6. OP
    OP
    Spanos

    Spanos Member

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    Disaster!

    So the odd y-axis shift completely failed out at the top of the print. So that's 150 m of filament in the bin!

    I pulled the sides off the printer this morning and checked the tightness of the belts and inspected all the pulleys. They are all fine which is not unsurprising since I've had hassle free printing from this machine for aaaaaaaaaaaaaaaages.

    I'm printing another benchy this morning to see if I can get the error to replicate again, but I doubt it will.

    So, I'm a bit unsure where to look now.

    I'll probably print another test print for the full height of the machine to see if it is height related.
     

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  7. Butcher9_9

    Butcher9_9 Member

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    Overheating stepper or driver maybe.
    Bad stepper driver maybe.
    Everything running smoothing at all heights, nothing binding?
     
  8. OP
    OP
    Spanos

    Spanos Member

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    I did consider an overheating stepper. The big failure at the top happened overnight (I print outside) when ambient temperature was about 5 or 6 degrees though.

    The benchy im printing at the moment is printing fine. I'm going to print a tall, narrow tower tonight and see if it does it nice and smoothly or if it triggers something.
     
  9. garfield2k

    garfield2k Member

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    question for ppl running multiple printers and a raspberry pi with octoprint/klipper etc.
    they both support multiple mcu's so should be able to run mutiple printers from a single pi device, would there be any potential drawbacks doing so? can the pi handle 2 printers both printing at the same time? anyone here run that sort of setup?
     
  10. Butcher9_9

    Butcher9_9 Member

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    I only have one printer but for Octoprint I could think of a couple assume you don't get separate octoprint instances.

    Cameras - They hit the CPU pretty hard ( at least for my Pi3) , 2 might be an issue unless you run very low res.
    Plugins - Some plugins might affect both printers at he same time. (IE Power relay control, emergency stop etc)

    I hear that Klipper can run on a Pi Zero with mainsail / fluid so a very low entry cost if you needed a second Pi.
     
  11. garfield2k

    garfield2k Member

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    some valid points. might do some more research. cameras would have to be usb i guess.

    as for pizero and mainsail or fluid -they work if no webcam. currenlty got pi3 with octoprint on the ender and mainsail/klipper on a pi4 on the v0. was thinking of converting the ender to klipper and maybe using the one pi to control them both. might be easier to keep it the way it is - knowing me ill have 2 printers not working if i try to play with it :lol:
     
  12. Butcher9_9

    Butcher9_9 Member

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    If you already have 2 PIs I would just keep them separate.
     
  13. Benno1988

    Benno1988 Member

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    Folks. In Cura, if I load in a model, slice it, and change all the settings to what I want (layers, temp, retraction, speeds etc) and generate the Gcode.

    Is there a way for me to save all those settings, so next time I load in a different model, all those settings are already set the same?

    Thought I might be able to generation a profile or set them to the printer, but seems like all the things that you tweak in the "Custom" part go along with that model?

    Only been using it a day, I imagine there is way.
     
  14. garfield2k

    garfield2k Member

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    you can save it in the profile drop down menu where you made all the changes.
     
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  15. OP
    OP
    Spanos

    Spanos Member

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    Started printing a second copy of a wall mounted bike rack. The first one I sliced into three parts and it took about 100 hours all up to print. I was using a matt black PLA and was really happy with the print with almost no defects at all.

    Before printing the second copy, I had changed filament over to a different filament and printed some other bits and pieces. So I chucked the black back in and let it polish up for two days in the filament dryer. Pulled a heap of moisture out of the PLA!

    Anyway, started the print and went out for a few hours. Came back to a spaghetti monster and a totally clogged nozzle. I was pretty confused because I didn't have any troubles at all with the first 100 hours of printing, so why this time?

    Printed a bed level test and I'm getting missing layers. yay. So i checked the nozzle and it seemed fine, even ran different filament through with the test print and no issues.

    Anyway, at a whim, cranked the temperature up to 220c for the black PLA and its happy days again.

    So now I am printing a temp tower to work out which temperature it should be printing at again.

    Filament is such a fickle thing, even the easy stuff. Even after proving that the print settings were great for over 100 hours of printing, I am now having to recalibrate.

    gotta love that 3D printing!
     
  16. OP
    OP
    Spanos

    Spanos Member

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    Measured the steppers today in the middle of a 3 hr print. Both the x and y steppers were at about 40 degrees and the chamber at about 30 degrees. So, definitely no dramas in the heat department.

    In fact, I haven't had the shift again since the first time it happened. go figure.
     
  17. apsilon

    apsilon Member

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    Think I may have messed up my hotend. I wanted to try a vase mode print with a 0.8 nozzle so heated it up, removed the 0.4 nozzle and let it cool to a point where I was OK screwing the new nozzle in with fingers specifically to ensure I didn't mess up the threads. Got it in finger tight and heated it up again to do the final tightening and when I was done the nozzle doesn't look level so I'm worried I've cross threaded it anyway. Running a print anyway and it's not leaking and seems to be printing fine but I still think it's going to be a problem. Suppose I should order a spare to keep on hand. Still need to dismantle for maintenance and to do the upgrade from mk3s to mk3s+ so when I do that I'll run a tap through and clean up the threads if necessary but worried that will result in it being too loose. Only ~$20 for a new block so not the end of the world but it's still annoying.

    Think I need a second printer rather than trying to swap nozzles regularly. Getting a lot of friends and family asking for vases and bowls and stuff that can be printed with vase mode but the walls are a bit thin for my liking with the standard 0.4 nozzle. Tempted to try a mini printer but would also like something larger. Would also like a resin printer for high detail stuff. Don't know where I'm going to put it all though.
     
  18. mtma

    mtma Member

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    Ah I change nozzles on hot heads using a hobby cross spanner like this. About 185 degrees after stabilisation usually has everything soft enough.

    The nozzle shape goes right into the largest hex and it's shallow so can't slip down into the spanner, and with the plastic sufficiently heated it's not that tight (also it only the cross provides just enough leverage to make it firm enough)

    Though they're made of some kind of zinc diecast (at least the Tamiya kit ones are) and heat up really quickly so it's not a great solution, if you could find a driver or socket and put something in it to hold the nozzle up it could be easier. I just basically do it really quickly with as minimum contact time with the nozzle in block as possible.

    The annoying thing though is that the heat block (I have an e3d v6 one) relies entirely on being rectangular to allow you to hold it from spinning but isn't really protruding with ducts around it and it's made of the softest aluminium they could find so mine is a bit mauled.
     
  19. apsilon

    apsilon Member

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    I have a heap of those from Tamiya kits over the years but I was using a 7mm socket and finger ratchet. The thing is I knew I was dealing with soft materials which is why I elected to allow it to cool so I could thread in just using fingers and only had to do the final nip up by tool so I'm not sure what happened. It threaded in easily so I don't see how I cross threaded it using my fingers (mine's also the E3D V6 as it's a Prusa). Agree it's a bit of a pain to hold the block in place. I was able to grab it with a small Knipex plierwrench. Anyway the 3 hour print finished without incident and without leaking so maybe it's OK. It sure appears to be slightly skew to me though. I'll see when I swap nozzles again but I may not do that until I have a spare in hand just in case. I almost did order some spares the other week when I ordered the other print sheet. In hindsight I should've as it's now going to cost more postage.
     
  20. OP
    OP
    Spanos

    Spanos Member

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    Gah, second failed print on the same object. Looks like the nozzle is clogging. It prints wonderfully until it clogs so I am thinking it is heat creep. just another excuse for a hot end upgrade :)

    Probably just gonna do a MK10 microswiss upgrade. cheap and cheerful, the creator pro is probably a bit old now to use as a base for upgrading. the newer prints look like they have some really good basics straight out of the box.
     

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