Print is taller than nozzle while printing

CR-10S 300x300, e3d Titan Aero direct drive, Volcano, Keenovo bed, TH3D firmware, no part cooling fan (temporarily), 210 C nozzle, 65 C bed.

Just installed an Titan Aero. Seems very nice, but my printer is doing something weird I haven't seen before. It prints a few layers, which look fine, then the model increasingly starts growing taller than the nozzle for the rest of the print. Everytime it goes around, it keeps pushing the model down, and it starts getting quiet messy. I assume that's an obvious case of overextrusion, or is there something else? It's almost like the Z-steps are off or something. I did change from the stock firmware to TH3D, so, there's probably something I didn't set right. I greased the Z rods, but that didn't help.

I went through all the instructions I could find several times and don't see anything I did wrong. I updated the E steps to 837, then tweaked them to 818 so it was extruding exactly 100mm. I'm using Simplify3D and my extrusion multiplier is set to 0.90, and using all my previous settings, except I reduced the retraction to 1mm for direct drive. Any idea?

It's interesting watching it print like this, and I'm surprised it's not making a bigger mess than it is. It'll eventually be printing 1/4" lower than the top of the print, just moving things out of the way as necessary, like it's a floppy piece of rubber. I didn't realize the material (PLA) remains that soft for so many layers while printing. Makes me realize how important it is to not try and yank prints off the bed immediately after it finishes. (btw, putting the whole glass print bed in the freezer for 5-10 min works awesome to remove prints - falls right off)

I can post my settings or upload my .factory file somewhere if it would help, but I don't think I have anything weird set in my slicer, and like I mentioned, it was printing perfectly fine before the Titan Aero, with the stock CR-10S hotend and extruder, and original firmware. Probably something with the firmware isn't set right...

never heard of th3d firmware. But it sounds like your z steps are wrong.

Thanks for the replay. I measured the distance between the gantry and bed (39.5mm), then raised it 50mm and re-measured (89.5mm), so I guess my Z-steps are ok. I attached a few pics above (partial benchy), which should give you a better idea.


If you look at the bottom layer, it doesn't really look overextruded to me? Looks like it was lifting off the bed at the corners a bit. The whole thing is kind of warped. My nozzle temp was only 210 (supposedly - new heater and new thermister, so who knows). Bed temp was only 65 F (through the glass bed, so more like 57 F according to my pyrometer. Not that hot. I could try turning each one down I guess and see what happens, but not sure what else to try. This isn't especially good quality filament, but I've been printing with it just fine. I did run a PID tune. The bed (keenovo) fluxuates up and down between 64-66 or so on the display, which seems fine.

It appears to be a version of Marlin 1.1.9 with a only a few change including modified configuration Files.

I think the th3d "unified firmware" is popular amoung us CR-10 guys, and maybe some others. I don't know a lot about it, but I was thinking it's the most common. I'm actually using it on my CR-10S S5 and it works ok. If there's something different I should try, please let me know.


Oh, I forgot to mention, I'm currently not using any cooling fan because the fan mount I had printed to use with the titan aero + volcano didn't fit the mount I printed. I don't think that's the problem though, since I sometimes print without a fan and it's just fine (and prints are stronger).

I was thinking maybe my nozzle temp is way higher than I think, but it looks like it's not. I kept lowering the temp until the titan aero started slowing down or making noise. Got down to 150 C! That thing doesn't give a crap hah.. I'm pretty sure the stock extruder would be mad. I also used a meat thermometer to get an estimate. When I had the nozzle set to 150 C, my thermometer read 122 CC on the outside, and when I had the nozzle set to 210 C, I read 180 C - not a good measurement I'm sure, since the contact area is small, but that shows it's not sky high at least. And I already verified the bed temp is accurate. Maybe I'll try different filament, or just aim a desk fan at it to simulate part cooling for now.

What size Nozzle are you using. I was looking at the Bottom of the Benchy by CT3D.XYZ and your filament lines widths are quite large.

I'm using a 0.4mm nozzle right now, and funny you mention that because when I was priming the nozzle, extruding into the air, I was thinking the same thing - it looked slightly wide. I wonder if the nozzle is messed up - I just use the cheapest nozzles from china - maybe they just suck sometimes. I have my extrusion width set to 0.4 right now; normally I use 0.48. Both seem to work ok, but 0.48 seems a little better in my opinion.


I think I maybe just figured out the problem though - lack of part cooling. I switched to different filament, and I got the same massive warping, then I printed the same file again with a small desk fan aimed at the nozzle - much better! It's not finished, but I don't see any crazy warping so far. So maybe it's just lack of part cooling, OR, maybe it's cooling the print bed. I typically set it at 65-70 C (which is roughly 8 C cooler for me on the surface of the glass), which is a bit higher than some people use (50-60 C).


The thing that's weird, I've never had these issues in the past using higher bed temp and no part cooling, so why now? Maybe a difference in thermisters? In any case, I guess I will add some sort of part cooling before I pull any more hairs out. Might also try reducing the bed temp a tad, and swap nozzles too since the one I'm using seems questionable. Thanks!

I usually run a width of .4 ~ .44, An have have always used the cheap brass nozzles without any troubles.
And hope we are both talking about PLA. I generally set my Nozzle to 196 ~ 202C and the bed temperature to 40 ~ 56C
1st layer no fan all others layers 50% fan speed.

Can you verify the Nozzle size by looking to see if it has an imprinted number on the nozzle. Some of my nozzles do and some not.

I have had them send me the wrong thermisters in the past. If you look and the Last picture in your 1st post.

You can see that the lines are spaced apart like you have a .4 nozzle and your slicers settings are set for .8 nozzle.
Then you have compensated and somehow got the CR3D.XYZ Benchy to somehow print.

Good news! I re-printed the same file, except I made it 50% in every direction this time since I'm impatient. Printed pretty good for being so small! The only other changes were adding an 8" desk fan aimed at the nozzle, and I lowered the bed temp to 60 C. One of those fixed it! Maybe the next print or two will confirm... I think I was actually cooking my prints with the bed temp being too high. This Keenovo pad dishes out some serious heat - maybe the temp readings are a little different.

I usually use a 120% extrusion width - some people think it's better, and I think that's the default in some slicers. And some people say equal to nozzle size is better. I guess I will experiment. Yes, I'm printing PLA today. Often, I use PETG - great stuff. About to try polycarbonate since I can do higher nozzle and bed temps now. =)

I often push the nozzle temps as high as possible unless I see significant problems, since the layers get stronger. Often 220 or even 230 C and it's usually fine. With PETG, I find it impossible to print high temps without a lot of stringing - I did a zillion test prints the other day and nothing I tried helped at all other than lowering the nozzle temp close to the bottom end of the range (stock setup - before titan aero).

I normally print the first layer with 0% fan, then 100% for all other layers. Maybe 50% is enough though - I'll try that (once I figure out how to mount a real part cooling fan). Oh yeah, in another series of tests I did, I found that the part cooling fan was causing tons of stringing with PETG. I've been printing PETG with no part fan at all since and the results are great.

I just verified it's a 0.4mm nozzle, and thanks for making me look - the heater block got loose somehow lol - didn't leak though.

So my nozzle is 0.4, and in Simplify3D I have the nozzle set to 0.4, but you're right, there is some spacing between the lines in the first layer. I've had this issue with both of my printers for a long time actually - the lines never touch. I already have the bed too close to the nozzle if anything - you almost cant pull the paper out when I'm leveling. I have to or the first layer won't go down right, or the print will fall off the bed. If I turn up the extrusion multiplier, that causes problems. I have it set at 1.00 now actually (not 0.90 like previously). And I already calibrated the extruder steps/mm so it extrudes exactly 100mm when instructed. Is there another setting I should try fiddling with in the slicer to get the lines to touch better?

Here were some of my main settings for the mini benchy I just printed: 0.40 nozzle, 0.48 extrusion width, 1.00 extrusion multiplier, 1.0 retraction, 100% first layer (default was 120%), 60 C bed, 204 C nozzle, desk fan for part cooling, 40mm/s. Just attached a few pics - remember that's a mini benchy. =) The red one is from months ago, just for size reference.

Ohhh!

I've Never Printed A Mini Benchy, Where did you get it.

Oh I just scaled the normal one 50% in Simplify3D that's all.

Well, just wanted to confirm, it was the heated bed melting my prints afterall - oops! The new heater must be getting slightly hotter than the old one at the same temp setting. 65 and 70 C were both causing severe problems. The bottom several layers must have been expanding slowly and pushing the whole model up - very strange.

I lowered to 60 C and the problem is fixed, except now it's a little harder to get my prints to stick to the bed. I was using elmers glue on glass, which worked great at 65+, but just now I switched to purple glue stick and that seems to hold stronger at slightly lower temps.

Also of note - having no cooling fan does not seem to be hurting the print quality - in fact I generally notice that part cooling makes print quality worse (opposite of common belief). I basically always have a little bit stringy and fuzzy prints with part cooling on, and ZERO with it off. For especially delicate parts, I think part cooling is necessary - little smoke stacks and things like that - otherwise, I think it's often a good idea to use no part cooling at all. I think I'll also try lowering the fan speed a lot. I think a lot of people just run them at 100% thinking the more air the better, but I'm realizing that's not true. That's my experience anyway.

Oh, one exception to that. On my bigger printer, I run a Volcano with 1.2mm nozzle at the fastest speeds possible. In that case, I DO think you want absolutely as much cooling as possible, or layers may just roll off the sides. I already have 2 high speed radial part coolers on that printer - maybe I will add a desk fan too and see what happens.

have you actually measured the diameter of the extruded filament ?
Much better than guessing :-)