Layer resolution range

[Brulti 177]

Hi everyone,

 

The demands of a customer spawned a question and I cannot seem to be able to find the answer on the UM website or this forum: what is the resolution range for the 0.4 nozzle of the UM3E?

 

I know that the lowest resolution is 0.02 mm, but what Is the highest? Can I print at 0.3 mm, for example? Or 0.35?

 

I guess that printing at 0.4 mm is impossible since the nozzle is 0.4, thus the layers would barely, if even, touch, and I'd probably end up with a bird's nest. But did anyone tried at 0.3, for example, and, if yes, what was the result? Did it affect the solidity of the print very much?

[fergazz 60]

Hi @Brulti!

I tryed 0.3mm with 0.4 nozzle... I never went above it. You need to print hotter and slower. I have a UM2 upgraded with Olsson block (3dSolex) I know that UM2 can handle around 7mm^3/s with the stock feeder, not sure about UM3 (anyone?)... so you need to calculate the volume: layer high x nozzle size x speed.

Exemple: 0.3 x 0.4 x 40mm/s = 4,8mm^3/s. You can go slower to get better quality, if you go faster print can underextrude if the object have a lot of retractions, you need to find a fine tune. You can also add more heat, around 5°C hotter than 0.2mm profile. With less layers and printing hotter the result will be probably more stiffer on layer direction. 

 

I hope that it helps, cheers!  

 

[Daid 306]

3/4 of a nozzle size is pretty much the upper limit for a layer height. So 0.3 is possible with a 0.4 nozzle. But with thicker layers, you want a larger nozzle size.

 

0.2mm is our highest layer height for our provided profiles for a 0.4mm nozzle.

[Brulti 177]

Thanks @fergazz and @Daid for your answers.

 

So, as I understand it, it's best not to use layer height that is higher than half the nozzle size (0.2mm for 0.4mm nozzle, 0.4mm for 0.8mm nozzle) but it can be pushed to 3/4 if we want to, but that's the upper limit, and you need to change a bunch of parameters to avoid under-extrusion and the like. Now I'm beginning to better see the usefulness of the 0.8mm nozzles...

 

So, for printing at 0.3mm, it would be best if I used the 0.6mm solex hardcore nozzle that I just received for testing abrasive materials. As @gr5 said, I can keep the same profile than the 0.4mm nozzle, change line width to 0.55mm or 0.6mm and I should be set.

 

I hope I got it right and it works, and I don't have to spend days fiddling with settings to print something that would take less than a day to print with standard settings. Customers sometimes... ?

[yellowshark 153]

There is absolutely no problem in printing 0.3 layers with a 0.4 nozzle; I have been doing it for 4 years plus. Just remember that the higher you raise the volume per sec. flow the hotter you need the extruder. So with the same settings .3 layers will be a greater volume than .2 layers. Not sure about the 0.8 nozzle, certainly no expert on that. Again with the same settings you will be pushing through twice the volume and the feeder speed will be doubled but your extruding orifice is twice as large so I assume the pressure will be the same but whether you need any increase in temp. I have no idea really. Checking back 3 years ago when I last used a 0.8 nozzle it looks like I did not increase the temp.

[Brulti 177]

@yellowshark Thanks for your answer. For printing PLA at 0.3mm layers with a 0.4mm nozzle, what temperature should I use?

[yellowshark 153]

It depends also on your print speed which you do not mention. Your optimum temp. will depend on your printer, your filament, the colour of your filament. And your optimum temp. could easily vary by 5 degrees either way from my optimum. My definition of optimum is the coolest temp. I can print at without under extrusion or any negative impact on the surface quality. 

 

With .3mm layers and a .4mmm nozzle at 30mm/s I would be in the region of 195-200 depending on filament

[yellowshark 153]

... sorry,that was for PLA; I use ColorFabb and Faberdashery; Ultimaker could be different.

[Brulti 177]

That still gives me a basis to work from, I'll have to make some tests anyway. Thanks for the info.

Edited May 18, 2018 by Brulti

[fergazz 60]

well, my profiles are a little bit diferent. I use the same settings for PLA/PHA and Ultimaker PLA just add more heat (2°C) for black color... as yellowshark said it can vary by printer to printer.

for 0.1 my average temp is 199;

for 0.2 my temp is 209 and

for 0.3 is 212. 

 

I read somewhere that UM3 profile in Cura for 0.8 nozzle and 0.2 layer high is hotter than 212... not sure if it was for a higher layer. I tryed to find this info in community without success I think that was posted by @tinkergnome... maybe @Daid can clarify it too

 

Cheers!

Edited May 18, 2018 by fergazz

[yellowshark 153]

With a 0.8 nozzle (3 years ago) I ran .300 layer at 40mm/s with a temp of 210. I suspect that these days I might run that cooler as in general I print cooler now than I did back in my early days. Then again I seem to printing 10 degrees or so cooler than you, although I have no idea what speed you were using; there are a number of variables so nothing is gospel although I think about 10 degrees is the limit, beyond that I would be suspicious of something being wrong.

[fergazz 60]

12 minutes ago, yellowshark said:

I think about 10 degrees is the limit, beyond that I would be suspicious of something being wrong.

me either... because of that I'm in doubt.

 

I thought that 220 was the limit for PLA but someone post that tinkermarlin firmware was setting wrong temperature for PLA (above 220) and tinkegnome said that this was equal for Cura profile... just don't remember which nozzle size and layer high was setted, damn! I cannot find it. ?

[fergazz 60]

just found it:

 

 

[Brulti 177]

I print at the default speed for the Cura profiles with PLA, only messed with that setting for other materials like wood and such

 

Ok, I know what to look for and thinker with when I try my print, thanks a lot! ^^

[Brulti 177]

For confirmation:

Standard settings with a 0.4 nozzle at 0.2mm layer and 70mm/s = 5.6mm3/s (0.4*0.2*70)

If I lower the speed to 45mm/s for 0.3mm layer and the 0.4mm nozzle, I reach: 0.3*0.4*45 = 5.4mm3/s

Since the flow of material is equal, I don't have to raise the temperature, right?

[fergazz 60]

I don't know if i'm to late but probably you don't need to raise the temperature. 

 

There is a test print for UM2 to reach the maximum cubic volume of your printer and to check if it's calibrated but it probably will not work with UM3 since you need to copy and paste the gcode... for those who have a UM2 it's avaiable here. Anyone else can download the print and edit gcode manually to adjust the speed. The edition can also be done in Simplify3D using diferent process.

 

Cheers!

[Brulti 177]

You're not late at all, I'm still not done and will resume my tests and such once I've finished a print for a customer.