Brand new Taz5 extruder problems

Hi All,

Just got my new Taz 5 for Christmas. Today I set it up and went through the “quick start guide”. When I got to the part where the printing begins (using bed_calibration.gcode) I ran into problems. I noticed right away that the first layer was very inconsistent with beads in places and very thin lines in others. I leveled the bed several times and checked the relative levels of the x and y axes using a digital micrometer. All of that seems fine. I raised the z axis up and did a bunch of extruding via the control panel in cura. That worked just fine, too (although I’m not completely sure what a problem would look like). I’m using ABS from IC3D. Originally, the temp was at 220 but I’ve subsequently tried 230 and 245 to no avail. In fact, the problem seems to have gotten worse because in the most recent couple of tries the “print” of bed_calibration produces almost no extruded material on the bed – again, this in spite of the fact that I can push the “extrude” button in cura and get a nice long thread of white ABS without any trouble. Any ideas about what I’m doing wrong or what to try in order to get this to work?

fwiw, I notice I have to push pretty hard in order to manually force filament through the extruder. Is it supposed to take a lot of force to do this or should it be relatively easy?

Since you are getting extrusion when you have the print head lifted off the bed I suspect that the home Z height is incorrect (too low). Place a standard piece of paper on the bed at the home position and home the print head. You should be able to pull the paper out and feel a slight bit of resistance. If the paper won’t move or if the print head creases the paper, raise the Z home height. Repeat this process until the paper can be pulled out with slight resistance.

BTW: I usually use a hot end temperature of 240C and a bed temperature of 110C when printing ABS.

Thanks George! That fixed it. About half a twist on the z-stop trigger adjustment. Now it’s happily printing. I had calibrated using a folded piece of paper (per the quick start guide), but I guess my idea of “some resistance” is different than expected :slight_smile: Now, with a folded piece of paper, there is very little resistance when the z-axis is homed, but it’s printing just fine, so no complaints.

Another thing to check too, you want about 8mm worth of space between the washers on the idler arm tensioner springs. If those are a little loose, you may want to tighten them. That will give you more nozzle pressure before grinding out. If it is printing fine where they are right now you can leave them alone, but generally they are a little loose when you first start printing.

Also, check and adjust z height when you are up to temp. The extruder and bed will expand when heated. If you adjust when everything is cold, once you heat up, the z height will be too small.

Also, when you do the bed leveling, be sure to check it in the middle of the platform. The mass of the extruder is offset from the centerline of the x-axis rods. As a result, the rods may flex a little when the head is in the middle of the x-axis travel. This would result in the head tilting forward slightly.

A good procedure might be to level the bed in all four corners, then move to the middle of the platform and fine-tune the z-axis homing.