First Print, Gaps in Extrusion

[nscali]

Hello All,

Noob here, just built my Rostock Max V2 this week. Loaded up Mattercontrol with the stock settings file and calibrated the machine according to the instruction manual, but I am having some major problems with my ABS prints. It seems like the extrusion is very uneven, and after watching it for a while I noticed that for the perimeters no filament comes out of the nozzle, only when the printer gets to the actual model will ABS finally start flowing, but it seems like the flow rate is waaay too low and my first layer adhesion is not good as a result. Also, it will flow for a while and stop, flow for a while and stop during the entire print, and you can hear the filament popping with air gaps constantly.

With the models I have gotten to print the plastic is choppy with irregular gaps every few millimeters. I originally though this was a z-height problem and have since adjusted both up and down i.e gripping a piece of paper so tight I can barely slip it under nozzle all the way up to the paper barely touching nozzle, but I am still getting consistently uneven flow rates. When feeding filament through manually I noticed it is initially difficult to force filament through but after a few centimeters it loosens up to the point where there is practically no resistance and the flow is totally smooth. I have felt for the amount of filament being fed during a print and it doesn't feel like filament is being fed very quickly at all, perhaps this is normal, but it seems like perhaps my extruder motor settings are wrong or the hobbed gear is not gripping correctly or tight enough.

Again this is all with the default ABS/standard quality settings straight from the website. But to be sure I have dialed up the temp to 235 and have dropped it down to 208 with no effect. On the heated bed I have tried Magic purple glue stick on the bare glass, as well as laying down a layer of kapton tape followed by glue stick and have gotten the same level of adhesion with both. Hopefully, it is just a stupid mistake I have made somewhere along the line and you all will have an easy fix for me, I appreciate any advice you can give!

Bottom of first layer showing gaps in extrusion

[Earthbound]

Is this ABS filament purchased with the machine or from a different source?

If you use manual controls to extrude a few mm of filament (with head at ~230C, and in home position high above the bed), does it come out in a nice consistent flow of even diameter?

I suspect a damaged or defective nozzle. It could be an extruder problem but it it was jamming/slipping you would likely have noticed and mentioned odd noises.

If the nozzle is OK, you might want to read up on extruder calibration (e-steps). Good video on youtube.

[nscali]

I upped my e-steps from the default 92.65 to 129.5 and dropped my z-height back to the level I felt was giving me the best consistency and re-calibrated my end stops which helped a LOT early on in the print, but im still not getting extrusion while my perimeters are being laid down, and further on into my prints im still getting gaps and inconsistencies. I guess I'm going to have to take my hot end off and inspect the nozzle to see if it is deformed at all. I may try upping my e-steps even more, but is it normal for it to be so far off from the recommended settings?

[nscali]

Got my hotend taken apart and sure enough the hole in my nozzle has gone from .5mm to 1.5mm. I have never even touched the nozzle, or let it hit the print bed hard... What could have caused this?

[teoman]

Cool.

Adjust the settings and try printing.

[guanu]

Got my hotend taken apart and sure enough the hole in my nozzle has gone from .5mm to 1.5mm. I have never even touched the nozzle, or let it hit the print bed hard... What could have caused this?

sounds like it was drilled too far and the tip blew out, email [email protected] with your order number and we'll take care of it for you

Guanu

[nscali]

Got my hotend taken apart and sure enough the hole in my nozzle has gone from .5mm to 1.5mm. I have never even touched the nozzle, or let it hit the print bed hard... What could have caused this?

sounds like it was drilled too far and the tip blew out, email [email protected] with your order number and we'll take care of it for you

Guanu

That seems to be the case, not 30 minutes after I had placed the order for replacement nozzles had seemecnc cancelled the order and sent me an email saying they were sending them to me gratis. Thanks a ton you guys!