massive webbing? or something else?

Hi, my printer arrived just before the holidays with a broken printer bed, i got a replacement within a week, so lets start the joy.
I calibrated, and printed the 5mm calibration cube several time with the PLA that came with the robot and reasonable good success for the first print. I ordered some new filament and printed a piece of ABS with good result. I then went back to make a piece out of PLA which i bought and that is when my problems started! After some tuning and tweaking i managed to get the filament extruding, but it didn't quit work out, the layers dont stick to each other and i got massive amount of webbing, or sometimes just the bottom layer. (see picture with black filament). After that it got even worse, i couldn't even get a first layer right, as if the extrusion flow was not consistent enough. Yesterday evening tried for the xxth time again, recalibrating , adjusting temperatures, adding some washer rings to the springs to get more pressure on the filament, with no luck (= no first layer). Then i changed back to the ABS (grey picture) again and in the beginning no luck, i used a needle to peek into the extruder nozzle and noted that the filament flow was much better now. The first layer is printing again (after calibration) and now i am back to the webbing again. As i am now getting a bit frustrated..... I think am ready for some hints on how to continue!

What causes this effect? is it temperature or inconsistent extrusion flow? Is my first layer not thick enough?

Any comments are welcome!

 

What temperature are you trying to print the ABS at?

 

Hi Matt and Mike,

tnx for the reply's, i think i found the problem. As Matt states the flow was inconsistent I noted that before but couldn't find why, as i just bought other filament i started playing with temperatures and recalibrating and as the flow was not consistent i added more washers on the springs to force the filament in (which resulted in a dirty hobbed bolt).
The trick with peeking a needle in the nozzle solved it, so i conclude that i had a partly clogged nozzle for the last two weeks, scraping it and applying more heat and pressure to the filament couldn't resolve it, luckily the needle did.

Mike i was running the ABS (grey) at 240 degrees, last night i switched back to PLA and now running my first prints again. I first ran the calibration cube in red PLA , which ran fine till half way (see picture), the top is missing here. i've also seen this in one of my previous test runs What could cause this?

then quickly printed the bed calibration tools on low resolution and a part of the glow in the dark haunted graveyard that both printed fine but i saw a lot of webbing between the parts. Both materials are PLA running at default temp settings (200 first layer, 190 other layers, heatbed 60 for the first layer and 55 for the other ones) the calibration tool was on low resolution and the graveyard on medium.


I think i am almost there and I guess it is a matter of fine tuning now, playing with temperatures and speed? what is the best thing to try first?
I also think i saw similar pictures of webbing somewhere on the forum, so i have to dig into that and see how is was resolved.

BTW What is meant with filament snag?

tnx for your help

 

Is that piece on the right supposed to be that misshapen? Is it possible that the hobbed bolt isn't gripping strong enough and both under-extruding and under-retracting? Under-retraction would cause this kind of spider webbing.

 

Thanks for the feedback
I have played with several settings, started with colder temperatures but that didn't help much. Then i tried increasing retraction length setting with no luck. Finally i increased the retraction speed from 30 mm/s to 33 with success, the webbing was completely gone, but the filament mechanism is very noisy then (due to play in the wheels), so i decreased to 32 mm/s which gives good results for my printer.