Not printing continuous line

[bryantp]

Hello,

I am having an issue where a print is not being printed in a continuous line. When the print head goes and prints the line, there is breakage in the middle. I am printing PLA

Here are my settings:

Line Height: 0.2100 mm
Temperature: 205
Fan: 100%
Printing Speed: 2200.0 mm/minute

Here is a picture of the print. It looks like the lines get squished towards the end.

Thank you for any help.

[Eaglezsoar]

After viewing the picture it almost looks like the cold extruder is slipping. I started out thinking that your bed calibration was way off
but the picture shows more of the hotend just quits extruding anything. Observe your cold extruder and make certain that the the center
of the two parts where the filament goes are aligned with each other. Is this problem related to this spool of filament or have you been
able to try a different spool? It is possible that the filament is undersized. Please get back to us on this problem. The picture is a great help!

[teoman]

I also believe it is due to bed calibration.

The slippage issue of the cold end could be related to that aswell. If the nozzle is too far down, then the molten filament has no where to go therefore the resistance increases, as the motor in the cold end is made of metal and relatively strong it starts to grind at your filament, after a few turns, it has carved a groove in the filament and the cold end does not have any more grip.

Observe the process very carefully, if you are over squishing, you should see that the moment the hot end rises, it "craps out" a certain amount of filament due to the pressure decrease.

But i am relatively a noob. And that is just my observation.

[Eaglezsoar]

I also believe it is due to bed calibration.

The slippage issue of the cold end could be related to that aswell. If the nozzle is too far down, then the molten filament has no where to go therefore the resistance increases, as the motor in the cold end is made of metal and relatively strong it starts to grind at your filament, after a few turns, it has carved a groove in the filament and the cold end does not have any more grip.

Observe the process very carefully, if you are over squishing, you should see that the moment the hot end rises, it "craps out" a certain amount of filament due to the pressure decrease.

But i am relatively a noob. And that is just my observation.

Your observation is correct. You appear to quite knowledgeable for a "noob" and are an asset to this forum.

[bryantp]

So, the bed may not be level thus causing the extruder to be clogged by the bed when it moves? This could be causing slippage of the cold end motor.

If this is the case, then leveling the towers would be the solution and then resetting the Z-height?

I shall make some more observations tomorrow. Printer isn't at my location.

[teoman]

Yes that is what I think is happening. And your solution should work.

A quick test would be to increase first layer height in the software. This will tell the machine to print the first layer higher. Your print will probably not succeed but at least you may observe what happens when the nozzle is slightly higher.

Or don't do any calibration and change Z height - Set new Z height on the printers LCD. Raising it by 0.1 or so. (Remember by how much so if it turns out not to be the case you can go back). The parts where you were detecting poor extrusion should be OK now but the other parts where you do have adhesion should have poor adhesion now.

[geneb]

*high fives teoman*

g.

[bryantp]

Well, I went and ran the Towers.gcode and adjusted the heights. The head was hitting the glass on the front two towers, so I adjusted them up. The right towers set screw is almost all the way down though. I also lifted the reel of filament as it may have been dragging.

It looks better, but I think I may need to make some more adjustments.

Here is an updated image. It is no longer breaking the lines, but I did notice some breakage here and there.

[teoman]

Looking better.
Unfortunately I have no further comments.

For further calibration using only software check out artmxg's thread. I got faster results using that.

And I woild clean the gear on the cold end. As you might have been using it as a cutting tool, it may be clogged causing filament to slip.

[bryantp]

Thanks for all the help teoman.

Unfortunately, I came back and found the printer in a little bit of a mess. Was this possibly caused by the temperature being too low? The printer stopped printing on its own, which is a nice feature.

[RocketMagnet]

I was seeing something similar but nowhere near as severe as your getting as I was getting tiny gaps which formed holes in thin walls.

Ultimately the head needs to stay level relative to the build plate/part also in the horizontal plane, for me it turned out my hot end wasn't down tight enough. (user induced btw )

I'm considering a dial indicator though as it seems like the easiest/only viable methodology for calibrating accurately. Squinting using your eyes is tough to judge imo and I'm of the general option if you can measure it you do so..

In the meantime I've been using my multi ring skirts and measuring the thickness around them as wont variations indicate where and by how much your calibration is out. So far mine have been pretty even thickness....Theoretically you could map out your calibration like this over the build plate?

[teoman]

You call that a mess? Atleast it did not waste material.

I came back home today and my printer had picassed...

[teoman]

Why did it pop out?

If you have damaged the aluminium , I have occasionally soldered a connector like that. Not easy to undo. And you must make sure you do not over heat the plastic parts.

But wait a bit for someone with a better idea. That is kind of a risky last resort that I use.