New Rostock Troubles

[cyber.shifter]

Ok. I was looking around for what could cause what I was experiencing, and I saw some things about calibration of the horizontal axis and z-stop calibration. However, I think it is an extruder problem. This is a picture of the print that I was working on last night when I had to stop it.

Failed PEEK fan print

So I started looking at it again today and it seems like the extruder isn't pushing the filament down the bowden tube. I can sort of push it manually, but not really. This is at temperature (which MatterControl set to 228 for this ABS material). I'm not sure why it printing a good part of the part before it stopped working. Any thoughts?

[cyber.shifter]

Also, when calibrating, I was allowing a pretty firm grab on the paper; basically right on the threshold of not being able to move it. Should I be going more for a slightly grabbing sensation? My thinking behind this is basically that the first layer will only be as thick as the paper, and this paper is kind of thin.

[Tincho85]

clogged nozzle maybe?
I can't print Blue abs at 228ºc, min FOR ME it's 240ºc with that material, but each brand is different.

Before cleaning the nozzle, try raising the temp.

[Dale Eason]

Also, when calibrating, I was allowing a pretty firm grab on the paper; basically right on the threshold of not being able to move it. Should I be going more for a slightly grabbing sensation? My thinking behind this is basically that the first layer will only be as thick as the paper, and this paper is kind of thin.

I hope you have a caliper that you can measure the paper thickness with. The first layer will be as thick as it is told to be by the slicer plus however much you were off the bed when you set the zero position on the LCD. In your case somewhat less than the paper thickness but probably not zero. If you know the paper thickness and then stop just as the hot end touches the paper then from the LCD panel you adjust the hot end down the thickness of the paper you truly have the hot end at zero. Otherwise you are off. Of course the trick is figuring out when the hot end just touched. Another way is once you get close measure the brim on a test print and adjust the zero position on the LCD to make to remove the error in the brim from what ever you set the first layer thickness parameter to in the slicer. All of this assumes you have gotten the horizontal radius calibrated correctly first.

Dale

[cyber.shifter]

clogged nozzle maybe?
I can't print Blue abs at 228ºc, min FOR ME it's 240ºc with that material, but each brand is different.

Before cleaning the nozzle, try raising the temp.

I'm using the SeeMeCNC's brand Brilliant Blue. It did seem like it was not quite melting it fast enough. But it put in the temp itself from the profile that I loaded from the download. Is there a way to ensure the thermistor is reading correctly? I guess that it's just assumed so, but I wonder. I will try printing it at 240. I have a digital angle meter coming in Saturday, and I'm going to double check all my tower angles as well. I'm going to try Dale Eason's suggestion too. Measure the paper thickness (if my caliper will do that, it's digital so it may) and then re-zero. I may look around for another calibration method too.

[Eaglezsoar]

clogged nozzle maybe?
I can't print Blue abs at 228ºc, min FOR ME it's 240ºc with that material, but each brand is different.

Before cleaning the nozzle, try raising the temp.

I'm using the SeeMeCNC's brand Brilliant Blue. It did seem like it was not quite melting it fast enough. But it put in the temp itself from the profile that I loaded from the download. Is there a way to ensure the thermistor is reading correctly? I guess that it's just assumed so, but I wonder. I will try printing it at 240. I have a digital angle meter coming in Saturday, and I'm going to double check all my tower angles as well. I'm going to try Dale Eason's suggestion too. Measure the paper thickness (if my caliper will do that, it's digital so it may) and then re-zero. I may look around for another calibration method too.

You can buy a meter that has a thermocouple option and place the thermocouple down into the hotend until it reaches the nozzle and verify temperatures that way.
There are many meters but here is a link to one that I like: http://www.amazon.com/AGPtek%C2%AE-Digi ... uple+meter" onclick="window.open(this.href);return false;

[Earthbound]

Thermistor could be reading low. Can verify with a thermocouple as as Eaglezsoar said. Low temp would make the EZstruder struggle to push the ABS. If the EZstruder is slipping, you should hear a sharp knocking sound when it slips.

If temp is ok...

In the setup process and calibration, did the nozzle hit the bed? Could have an obstructed nozzle if the tip crushed down at all. I killed a stock nozzle with a bed strike once.

[cyber.shifter]

I can check the nozzle. The first calibration pass did sound like it hit kinda hard. But then, how would it have print the first half of the object ok? I did see some slipping of the extruder, and when I pulled the filament out, it had wear marks showing it slipped. I'll be home in a couple hours and I'm going to try just running the calibration cube with a higher temp and see if that does it. Speaking of calibration, is there a better recommendation than the stock calibration method that I should know about? I saw some people tossing about scripts for calibrating, but wasn't sure how that worked.

[drwho]

The globs look like its too tight to the bed. Try backing off the bed a bit. Also would turn up the heat to at least 235C

If your using thin copy paper try this. See if it moves and then remove the paper and try to put it back under. If you can't get the paper back under the nozzle its too tight. It should be easy to put back under, but still have drag.

[Dale Eason]

...But then, how would it have print the first half of the object ok? I did see some slipping of the extruder, and when I pulled the filament out, it had wear marks showing it slipped. ...

There is a good clue. It worked pretty well at first. So it appears to have stopped extruding the correct amount after awhile. Causes could be:
1. Hot end cooled off because heater stopped.
2. Nozzle clogged for some reason possibly because the temp was too low for that filament and your setup.


It can be helpful to measure the actual temp of the nozzle, however you also have a relative measure. That is to raise/lower the temp until the filament extrudes properly. Assuming you don't exceed the max temp range of your extruder if you can.

Dale

[cyber.shifter]

I backed off some on the calibration. Got it calibrated completely.I raised the temp on the extruder to 240 and it still seems to have trouble extruding still. The dispensing of the material seems to be delayed, as if it is not hot enough. I ran the PID autocalibrate again and got slightly different values, so I input those. Still the same. I back-fed the filament, then disconnected the Bowden tube and tried just inserting the filament directly. I still had the same issue. So it seems the nozzle is clogged? Not sure what to do about it...

[Dale Eason]

I backed off some on the calibration. Got it calibrated completely.I raised the temp on the extruder to 240 and it still seems to have trouble extruding still. The dispensing of the material seems to be delayed, as if it is not hot enough. I ran the PID autocalibrate again and got slightly different values, so I input those. Still the same. I back-fed the filament, then disconnected the Bowden tube and tried just inserting the filament directly. I still had the same issue. So it seems the nozzle is clogged? Not sure what to do about it...

My nozzle got clogged recently. Bring it up to temp and the without burning yourself unscrew the nozzle. Once it is apart you may find that the clog is further up the hot end. Then it is easy to fix. Take out the PTFE tube and manually push a solid wire about the size of the filament into to it to clear it. You may also be able to push filament instead of a wire.

If the clog is actually in the nozzle and it is ABS then you may be able to clear it with soaking in acetone. However it should have melted at the temps you had. So if it is not ABS clogging it you must use some other methods. Some have suggested needles.

Dale

[cyber.shifter]

I will try this now. I also have a torlon hot end I may try eventually. Gotta check to see if it is 1.75 mm though.

[cyber.shifter]

There was some residual plastic in the nozzle, but I'm not sure what constitutes "clogged". I am able to push filament through, but it requires more force than it should. This is at 240C. I noticed that when I pull the filament out of the hotend, it seems melted quite well, but it still is not coming out of the nozzle. It is ABS, so I will try the acetone soak tomorrow. I do not have any at my disposal here tonight.

[Tincho85]

Remember to heat the hot end before removing the nozzle.

[cyber.shifter]

Ok, So I had some success unclogging the back end of the nozzle, but no amount of acetone seemed the penetrate enough to get through the extruder tip. I'm going to try heating it up again, and seeing if I can clear it while it is hot.

[cyber.shifter]

Got the nozzle cleared by heating it up. Used a single strand of the 18 gauge wire to do it. Also, reflashed the firmware and re-calibrated, this time with less "grab" on the paper. Finally, did a test print with the extruder temp set to 235 and got much better results.

Calibration Cube!

It's only the calibration cube, but the layers look much better than before.

[cyber.shifter]

Still having trouble with printing. Second time I'm trying to print the PEEK fan shroud. I'm not sure what's going now.. The second time looks much better on the layers, but they both ran into the issue at almost the same layer.

Printed PEEK fan shroud failures.

[Dale Eason]

My guess is that the hot end temp is too low. It is just on the edge of being too low and eventually the hot end plugs. I would try increasing the temp by 5 or 10 deg as an experiment.

Dale

[cyber.shifter]

I'm currently printing it at 235. If I up it to 240 that's getting close to my ceiling of 245. The only reason I get nervous is that I noticed that the one or two times I heated it to 240, it went up to 245 briefly before it settled down to 240. I'm just nervous about it overheating. Should I be worried about that?

[stonewater]

telling ya you need a thermocouple for your multimeter... figure out what it is really doing.. your temp is too low if your nozzle is clogging. nevrer had a nozzle clog except 1 time with abs from not having my peek fan running and heat creep melted the abs up into the Bowden tube inside the peek/.


Tom C

[cyber.shifter]

I did notice the two times that I unclogged it that I had melted ABS in the PEEK tube. However, the thermistor read that it was at the temperature that I wanted. If the thermistor is reading off, is there a way to correct for it in the firmware or something?

[Mac The Knife]

http://forum.seemecnc.com/viewtopic.php?f=36&t=5562

[Tincho85]

Do you have a spool of natural filament? (Not white). It works better with lower temperatures.
In my experience, darker colours needs to be printed the hottest.

[cyber.shifter]

http://forum.seemecnc.com/viewtopic.php?f=36&t=5562

Excellent! That is what I was looking for! I'm going to have to see if my fluke does temperature readings. If not, I'll just grab a decent one on Amazon and use the Fluke as a second meter for reading the resistance.