I am having an issue with a TAZ 5.

3D Printing
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1

I am having an issue with a TAZ 5. I bought it used and everything is in good shape. However, when I go to extrude filament it just grinds a notch into the filament. So I have adjusted the tension various times. This happens with ABS at 240C and PLA at 205C. It will extrude a little bit of filament and then the flow rate slows down and I can feel the filament (going into the extruder) having back pressure. But the nozzle doesn’t seem to be clogged.

I tried another HEX toolhead on it that I know works on another TAZ 5 and it does the same thing. When I do manage to get the faulty TAZ to print it extrudes much thicker lines of filament and the bottom layer “fill” is very blobby. After a while it ends up grinding the filament and stops feeding so the print fails. The same gcode file on the other TAZ prints just fine. The nozzle has a “3” on it which should confirm that it is the Lulzbot .35mm nozzle.

So I tried raising the temps. I printed PLA at 235C and ABS at 265C. I know this is too hot for these materials but it extruded fine with little to no back pressure and no filament grinding. But if I print with that temp it just comes out bubbly and not precise.

That makes me wondering if I need to do a PID autotune? I tried calibrating the E Steps at the higher temps and it seemed to be fine.

I am wondering if this is a software related issue. Although I have re-flashed the firmware multiple times now.

Any help is appreciated.

Thanks

2

It sounds like your thermistor is broken or needs calibration.

3

Have you contacted lulzbot support? They’re pretty awesome at helping solve issues like this.

4

@Justin_Nesselrotte Do they still offer support help if I am the second owner?

5

@Brahk_Szchank ​ most likely, yes. I think they’d rather you just be back to printing. They may or may not offer you replacement parts if you’re the second owner, but the only way to know is to ask I guess.

6

If the temp is ok, you could have a blockage. Mine started doing the same thing after I ran a spool of problematic filament through it. I ended up doing a total rebuild of the hotend. And everything is great again.

7

@Keith_Applegarth Was that on a TAZ 5? What did that entail? Just disassembling the hotend and cleaning everything?

8

No. It is a Prusa i3. I googled it and found a couple of videos. It wasn’t that hard. But it would have been easier with spare parts (nozzles and tubes).

9

If you can’t manually push the filament through (by disengaging the drive) then your nozzle is blocked. Otherwise the bolt may not be engaging the filament properly - try loosening the 2 tension screws to get the bearing to press down harder on the filament.

10

Hey guys I think I may have found the issue but need help finding the solution.

Sound stupid, but when compared to another TAZ 5, the extrusion rate of my TAZ 5 is much faster (Large herringbone gear is spinning quite fast). This would make sense if it’s trying to extrude faster than it can melt the plastic.

However, the weird thing is it has been reflashed to the original firmware. So I have no idea why/how to change the extrusion rate within the LCD of the TAZ.

Any help?

11

I don’t remember the menu layout on the TAZ5’s, but I know you can use the M92 gcode to change it.

12

@Brahk_Szchank http://m.youtube.com/channel/UCb8Rde3uRL1ohROUVg46h1A
He has a video on calibrating your extruder and walks you through saving the settings too.

13

@Justin_Nesselrotte So that is extrusion rate? Is there any Gcode to see the current rate settings? Thanks