New roll, clog in the middle of a 24h print...

This morning I installed a new roll of Z-ABS (black) and started a somewhat longer print. It was the 15th or 16th time that I printed the same zcode file.

I watched the raft laying to be sure it starts ok and then left.

One hour ago (13 hours into the print) I went to look at the progress and found the hotend full of extruded ABS and a mess on the bed.

After the tedious, from extruder gear to nozzle, cleaning process was finished, now I'm printing again.

The first time that it happened I cought it in time and managed a quick clean. That was for sure some impurity inside the filament.

I use a big filament cleaner sponge, also the roll was free to move.

This raises a question: what happened to Z filament quality?

It looks like both diameter problems and impurities that happen pretty often (at least to me).

I have 2 rolls printed without problems and 2 rolls with problems. I don't count here the free roll of white ABS that was a complete mess.

Ideas:

- instead of a still not working WiFi, a working filament sensor that can pause the print when a clog occurs wouls have been more appreciated.

- the printer is temp locked so why not allow for a spring loaded idler on the extruder? At least this would solve the diameter problems...

 
PS: don't get me wrong, I love the printer, the quality of the prints and how easy it can be operated.
I just find it a big bummer to have such trivial problems that could be solved easily.

The adjustable idler would be a nice addition to the printer, I just took ours apart today to find out what it looked like inside the print head. I was surprised to find the bearing locked in place, an interesting choice but not uncommon. If you bought direct from Zortrax then you should contact them about getting an exchange of filament spools. (not sure how they handle it but it is what I would do) same goes for what re-seller you might have gotten it from. 

-Michael

Why does a clog cause a mess on the extruder and on the bed?

Not sure what the problem might be.. I've been through 25 spools or so the last year..(only one plugged nozzle) David Barwin said he has used 58 spools of black Z-ABS without a problem I believe..

Michael, I already have Z filament from 2 different resellers, don't know where this specific roll came from. And just the cost is not important.

Andre, the mess was caused by randomly extruding filament in air, sticking it all over the heatblock. The bed was a mess because the printed part was not looking like it should have been ;)

Kyle, random problems occur sometimes in big production batches, it is understandable. If nobody says a thing then Zortrax can't make the producer aware of problems.

I guess that all activity on this forum is because we all like the folks at Zortrax and want them to be better.

There are no true ill meaning comments just nudges to be better. At least this is the case for me but this is the way that I see other comments too.

PS: It might have been because the drive gear had some filament debris between its teeth. Or a combination of three causes that each one alone couldn't cause a clog: small diameter variance, filament debris on drive gear and a small speckle inside the filament causing the clog.

I will try the same roll during the weekend and watch it print.

I have also had black Z-ABS clog for me before.. And it is the same spool that is hard to remove the raft and support from.  I don't know if it is something to do with the color or just happened to be a bad spool.

I have found black ABS (not just from Zortrax but from other sources as well) to be more problematic than lighter colors - more difficult to remove raft/support, etc. Maybe because of higher dye/solids content?

Caesar, I think Andre's question was how can you have a mess of extruded plastic if the problem was due to a clog, since a clog should prevent extrusion. I guess the answer is that there was a momentary failure that prevented extrusion for a time, then extrusion resumed later after the z-axis had moved down, causing the mess. But in that case the problem might have been not a clog (since those tend not to be self-clearing) but a slippage of some kind, perhaps caused by a spool tangle.