Question about the .25 nozzle...

[themskel 0]

I was looking around at some specifications on the different nozzles and noticed that the max resolution for the .25 nozzle was 60 microns. Can someone explain this to me? Why can't the .25 print with a higher resolution than the .4 nozzle? Any help is much appreciated. Thanks.

[gr5 2,172]

Good question. I haven't tried the .25mm nozzle yet but I have one (I have a .15mm also).

I'm just guessing. Either no one really proofread the specs carefully who had tried a .25mm nozzle. Or it might be that you really can't go lower than .06mm layer height for that nozzle.

PLA is kind of gunky/sticky as you are printing and it sticks to itself like snot or like a liquid rubber band. When printing very thin layers it may be that it has trouble and these liquid strands break and don't print so well when it's so thin to start with (.25mm across). I really don't know. Hopefully someone else knows the answer.

[Tomhe 21]

The resolution of the 0.25mm nozzle is no longer limited by the nozzle design, but by the amount of steps of the feeder. When you go below 0.06mm layer height, it can happen that the amount of material that should be extruded is less than the amount extruded by one step of the feeder motor. This means no material will be extruded when trying to print really small features.

From what I've seen, the difference between 0.06mm layer height and even lower layer heights is hardly noticeable.

[Labern 774]

I have printed with the 0.25mm nozzle at 0.04 regularly and quite successfully.

[themskel 0]

Thanks for your replies.

[ultradryan 9]

I have printed with the 0.25mm nozzle at 0.04 regularly and quite successfully.

Hi can u share the settings of your profile?

I want to know about the line width, layer height, flow rate and print speed. I kind of not printing very well with my .25 nozzle.

[Labern 774]

This was printed with CURA 15.?? And a lot has changed since then which should make it a lot easier.

You have to think in terms of mm3/s filament flow though you hot end.

A standard 0.4 nozzle x 0.1 layer height x 30mm/s = 1.2mm3/s can be printed at 195deg with excellent results.

So a 0.25mm nozzle x 0.04 layer height x 30mm/s = 0.3mm3/s a big difference from the above.

This shows the filament is moving a lot slower though the hot end. This means at your standard temps it has more time to absorb the heat , become less viscous and build less pressure in your nozzle. (Your print will be too hot) so this means you can reduce the temp heaps.

I don't have a set profile and adjust per model depending on the design as if I'm using the smaller nozzles means I want top quality.

[ultradryan 9]

This was printed with CURA 15.?? And a lot has changed since then which should make it a lot easier.

You have to think in terms of mm3/s filament flow though you hot end.

A standard 0.4 nozzle x 0.1 layer height x 30mm/s = 1.2mm3/s can be printed at 195deg with excellent  results.

So a 0.25mm nozzle x 0.04 layer height x 30mm/s = 0.3mm3/s a big difference from the above.

This shows the filament is moving a lot slower though the hot end. This means at your standard temps  it has more time to absorb the heat  , become less viscous and build less pressure in your nozzle. (Your print will be too hot) so this means you can reduce the temp heaps.

I don't have a set profile and adjust per model depending on the design as if I'm using the smaller nozzles means I want top quality.

 

I see...

Originally I was working on layer height in 1/2 of nozzle width at:

0.25 nozzle / 2 = 0.125mm layer height

I do this on 40% flow-rate and 20mm/s.

I didnt know it is possible to get down to 0.04 layer height

So you think it's good idea if i start printing from this:

0.25mm nozzle x 0.04 layer height x 30mm/s = 0.3mm3/s

then gradually adjust the temperature to get a good print is a good start?

You also mentioned that the temperature is too high becuz the material is moving slower. Do you think flow-rate will be affecting this factor? Or do you print it in 100% flow-rate?

Please dont mind me asking, I am using a 3DSolex nozzle, the print core is easily clogged and it never succeed in unloading filament(filament sticking too hard to the print-core), you think what will be the main cause for this? I heard a few 3DSolex users also hv similar issue, just want to know if this is a normal behaviour for the product or if it's a user's fault.

sorry for a lot of questions asked here

[gr5 2,172]

If I remember right the minimum temp is 170C (or 175C?).  If it dips below the minimum temp the extruder stops rotating and the print basically fails.  So I recommend at least 5C above the minimum temp.  There is a gcode that will disable this feature but it's possible that the printer will halt anyway - not sure.

I've certainly printed at 190C and I think I printed at 180C once also.

[Labern 774]

 

This was printed with CURA 15.?? And a lot has changed since then which should make it a lot easier.

You have to think in terms of mm3/s filament flow though you hot end.

A standard 0.4 nozzle x 0.1 layer height x 30mm/s = 1.2mm3/s can be printed at 195deg with excellent  results.

So a 0.25mm nozzle x 0.04 layer height x 30mm/s = 0.3mm3/s a big difference from the above.

This shows the filament is moving a lot slower though the hot end. This means at your standard temps  it has more time to absorb the heat  , become less viscous and build less pressure in your nozzle. (Your print will be too hot) so this means you can reduce the temp heaps.

I don't have a set profile and adjust per model depending on the design as if I'm using the smaller nozzles means I want top quality.

 

I see...

Originally I was working on layer height in 1/2 of nozzle width at:

0.25 nozzle / 2 = 0.125mm layer height

I do this on 40% flow-rate and 20mm/s.

I didnt know it is possible to get down to 0.04 layer height

So you think it's good idea if i start printing from this:

0.25mm nozzle x 0.04 layer height x 30mm/s = 0.3mm3/s

then gradually adjust the temperature to get a good print is a good start?

You also mentioned that the temperature is too high becuz the material is moving slower. Do you think flow-rate will be affecting this factor? Or do you print it in 100% flow-rate?

Please dont mind me asking, I am using a 3DSolex nozzle, the print core is easily clogged and it never succeed in unloading filament(filament sticking too hard to the print-core), you think what will be the main cause for this? I heard a few 3DSolex  users also hv similar issue, just want to know if this is a normal behaviour for the product or if it's a user's fault.

sorry for a lot of questions asked here

 

Never adjust your flow rate. Maybe sometimes increase it by 10% for carbon fiber or something.

Flow rate is auto calculated when you set your speed, layer height and nozzle size. So if you drop it to 40% you are dropping it well below what it should be at.

Yes just play with the temps and as Gr5 says only go low as 175deg. If you need to go lower you have to put M302 in the start gcode which is "allow cold extrudes"

I have printed at 155deg before but you will never need to go that low.

I also had bad experiences with the 3Dsolex core and gave up. I only need small nozzles for single extrusion so just use my UM2+ but I am planning of testing the 3Dsolex core again sometime soon.

[ultradryan 9]

Never adjust your flow rate. Maybe sometimes increase it by 10% for carbon fiber or something.

Flow rate is auto calculated when you set your speed, layer height and nozzle size. So if you drop it to 40% you are dropping it well below what it should be at.

Yes just play with the temps and as Gr5 says only go low as 175deg. If you need to go lower you have to put M302 in the start gcode which is "allow cold extrudes"

I have printed at 155deg before but you will never need to go that low.

I also had bad experiences with the 3Dsolex core and gave up. I only need small nozzles for single extrusion so just use my UM2+ but I am planning of testing the 3Dsolex core again sometime soon.

Thanks, I learnt a lot here.

Just notice now that this thread isnt specifically about UM3 printers, but I only got a UM3 so the 3dSolex print core is my only option right now.

If you are able to perfect the print on .25nozzle on UM3 I would very much like to know how it goes

[ultradryan 9]

I've certainly printed at 190C and I think I printed at 180C once also.

Are you using 3DSolex core on UM3? I am curious to know if you have encounter same issues on it.

I never get to unload filament from the 3DSolex core successfully. Instead, I hv to manually hit up nozzle to do a hot pull. The filament often got stuck inside print core. This happens on all sizes of nozzles. Does this happen often to you or just me?