Traces Too Thin?

Lately the traces in my prints have been too small in diameter to fill in solid layers and join up with each other even around the perimeters. The image below shows some bad gaps and even holes in the top layers of the print. This is PLA, 3 mm, 3 solid layers and 3 perimeters.



The PLA is about 3 weeks old, and I have definitely seen some signs of moisture in the material--puffs of smoke and sputtering, oozing including oozing some water. I suspect that the absorbed moisture is somewhat to blame for the bad trace outputs, but please advise if there is something I should check.

D

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[DMillerRepRap.blogspot.com] -- 3D Printing Blog with Pics, Videos, etc. -- Please view and leave your comments and advice!

Print a single wall test piece and measure it, compare to the expected value and adjust the esteps.

I would run to the Dollar Tree (if in the USA) and get a couple of those big closet dehumidifiers and some LARGE sealable boxes (only a dollar a piece so get a few extra for your extra reels). Stick the reel of PLA and the dessicate/closet dehumidifiers (opened of course) in the box and let it sit there for 2 or 3 days. Once you have done that see what happens and store your PLA in that box with the dehumidifiers/dessicates and it really should help.

Edited 1 time(s). Last edit at 09/09/2012 08:33PM by Dark Alchemist.

have you checked the diameter of the feedstock you are using, also it may be possible your extruder has been grinding the feedstock, take apart your extruder and clean the griping area of bolt.

also is your bed really level? temp changes and moisture have made beds not level before. if you have wood base this may be an issue, otherwise also check that bolts are tight, and that rods are straight.


feedstock may be moist, but i have has some pla outside of package for over 9months. it is clear pla, and from makerbot. I don't know if some other brands are same or not. usually i have moisture issues with abs. abs absorbs up to 1% in volume of moisture a few days

from google [www.curbellplastics.com].

Wow, 1% per day? The place I live sits at about 40%-50% (50%-100% outside) humidity every single day and only a handful of days a year do we have little humidity (20%-30%).

I guess the box and the closet dehumidifiers from the Dollar Tree (I mention them only because they are a dollar but can buy anywhere for up to 8 dollars) are absolutely needed for the ABS and I doubt would hurt for PLA either.

The advice about the dehumidifier is good. To get rid of the moisture in the filament quickly, you can put it in the oven at around 150 C, or 300 F for a couple hours. That is what I do to get rid of the moisture in Nylon weed trimmer line so that it can be extruded.

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I am a printrbot owner who refuses to pay for expensive filament anymore. I started using Nylon weed trimmer line, which is about a third of the price. Instructions are here:
[reprap.org]

If yu use slic3 - you can follow this single wall cabration method - [github.com]

I bet you PLA is moist, but I doubt that is the "end all" of your troubles

I printed a single wall calibration object last night and did find that the wall thickness was well below what it should be. Adjusted the steps per mm setting in Marlin and reprinted and it appears to be much better.

I plan to make a few more calibration prints tonight and then print out a few parts overnight.

The frustrating thing is, I calibrated my esteps before and thought things were great but I must have made a mistake--compounded by not re-slicing objects before I reprinted some older pieces. Then when I stated printing a few newly sliced parts I started seeing the thin traces. Long story short, too much work done late at night with my eyes getting heavy, so mistakes were made. Live and learn . . .

D

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[DMillerRepRap.blogspot.com] -- 3D Printing Blog with Pics, Videos, etc. -- Please view and leave your comments and advice!

This is also the sort of problem I see when I set the extrusion multiplier too low in Slic3r.

After following the advice above and recalibrating my extruder steps per mm my print quality is back to what it should be. Turns out the possible water absorbtion by the PLA was not a significant contributing factor, although I'm sure it's having some effect.

Thanks again everyone!!!

D

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[DMillerRepRap.blogspot.com] -- 3D Printing Blog with Pics, Videos, etc. -- Please view and leave your comments and advice!