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Inconsistent flow ?
 
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Inconsistent flow ?  

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Brandon
 Brandon
(@brandon-2)
Active Member
Inconsistent flow ?

Not sure what is causing this, but I recently replaced the nozzle thinking it was a partial clog. I am cleaning the bed with very high alcohol content wipes and I believe the bed is very clean...

I am using hatchbox PLA and temp on print is 215/60. I found with earlier prints that 215 seemed to work better than 205...

Any help or recommendations would be appreciated.

Posted : 28/03/2019 9:45 pm
bobstro
 bobstro
(@bobstro)
Illustrious Member
Re: Inconsistent flow ?


[...] I am cleaning the bed with very high alcohol content wipes and I believe the bed is very clean...

Adhesion problems are usually caused by 2 main problems:

  • A dirty PEI print surface. Even if you don't think this is the cause, it's always a good idea to make sure your PEI surface is clean before trying any other fixes. Take it to the kitchen sink and give it a good dunk with Dawn (original formula, no vinegar or hand softener variants) dishwashing soap or your local equivalent (e.g. Fairy in UK). Use a clean paper towel to clean it off, and another to dry it. Avoid using any sponge or cloth that has been in contact with grease. Above all else, avoid touching the PEI print surface. Once it's good and clean, you should be able to use 91%+ isopropyl alcohol between prints, 100% acetone when that fails, and another dunk when acetone fails.

  • . If you have not already done so, try using Jeff Jordan's "Life Adjust" procedure for calibrating your Live-Z setting. It is much easier to use and understand than the on-board routine.

    • Try those 2 steps. If you're uncertain of the Live-Z results, post pics here of the 75x75 print bottom and you'll get quick help. Looking at the pic, I'm going to suggest your Live-Z adjustment is too high (not negative enough). In general, start high (less negative) and work lower (more negative) in large increments (e.g. 0.1mm) until the filament starts to stick on its own. When it's right, you should be able to gently rub it without it coming loose. Then start lowering (more negative) the level until there are no gaps between layers.

    After you've done those 2 steps, if you're still having problems (I see what you mean about it petering out on the right), update and we can proceed knowing that it's not an adhesion or Live-Z problem. You swapped nozzles, so a partial clog is unlikely. Idler tension perhaps?

    My notes and disclaimers on 3D printing

    and miscellaneous other tech projects
    He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan

    Posted : 28/03/2019 9:57 pm
    Brandon
     Brandon
    (@brandon-2)
    Active Member
    Topic starter answered:
    Re: Inconsistent flow ?

    I can't really even get through calibrating my z-setting...

    Towards the end of the print I squeezed the filament going into the hot end and applied a downward pressure... that seemed to fix the problem. I need to figure out how to adjust the filament feed into the hot-end....

    Posted : 28/03/2019 10:58 pm
    Brandon
     Brandon
    (@brandon-2)
    Active Member
    Topic starter answered:
    Re: Inconsistent flow ?

    Fixed - I removed the idler tension bolts and then tightened back up (only much less tight). They were overtightened and likely squeezing the filament and prohibiting a smooth feed.

    Printed out the life adjust with a z adjustment of -.500 mm and everything is looking smooth.

    Posted : 28/03/2019 11:02 pm
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