Super hard nozzles - Test pilots

[Titus]

Yeah, I can look down the nozzle and see the light

[Neotko]

New test looks very very very nice

70mm/s 210C olsson nozzle 0.1 layer (same gcode as the first post video)



Using my new fancap for umo on um2 hotend. I might be able to pull a perfect robot at 50mm/s. Ofc ruby nozzle it's simple amazing.

[Neotko]

Awesoooooomeeeee!!!! 38minutes print time.



Btw this is using red (slightly transparent) very very cheap from benq.

[PeggyB]

Finally had time to mount the ruby nozzle to my UM2Go, because I am using my UMO's with a 0.8 nozzle for bigger prints these days.
And there is a noticeable difference!
Printing in rPET the material is much more translucent compared to the brass nozzle and I could print cooler.....
Because of the material presets in the UM2Go I sometimes forget to change the material before, so the PET starts with the 210 degrees preset. With the brass nozzle the print would be white and start to suffer from the low temp, but the ruby nozzle would finish the print translucent with no problem..
Dialing to temp to 220 works great of coarse and the print had a more cleaner outside with less 'blobs' then before.

left brass, right ruby

left brass, right ruby

[Anders Olsson]

Sorry everyone for not posting here lately, I have been very busy with family matters, I will try to catch up a bit coming days.

Ooops...
_D7A9956.jpg

Regarding this incident, we concluded that the main reason was way too high tightening torque (3Nm) in combination with the UMO heater block design. I can only blame myself though as the instructions were a bit unclear in an earlier post, which I have now edited.
Recommended tightening torque for the ruby nozzle is 0.25-0.5 Nm (use the torque wrench)
3 Nm is actually difficult to achieve unless you use a properly large wrench-. If you are using a small nozzle spanner and tighten the nozzle gently you should not risk destroying it.

The one interesting thing is that I had to bump the hot end temperature up from 255C to 270C to get it to print without the extruder kicking back.

The thermal conductivity of the nozzles will vary a bit, I am working on fixing that for the next batch, but thanks for the feedback!

Actually, Anders, the Ruby nozzle, is that still partly a secret on UMforums? I haven't really read anything about it there, and I was about to post a picture, which I ended up not doing, just in case.

I did a post about it on the (new) UMforum long time ago but there was basically zero response.
That was one reason for starting this forum actually, since a large part of the advanced community appears to have ditched the official UMforum after the upgrade.

Regarding the feeding, I think you are also seeing effects of thermal conductivity that I hope to fix on the next batch.

Finally had time to mount the ruby nozzle to my UM2Go, because I am using my UMO's with a 0.8 nozzle for bigger prints these days.
And there is a noticeable difference!
Printing in rPET the material is much more translucent compared to the brass nozzle and I could print cooler.....
Because of the material presets in the UM2Go I sometimes forget to change the material before, so the PET starts with the 210 degrees preset. With the brass nozzle the print would be white and start to suffer from the low temp, but the ruby nozzle would finish the print translucent with no problem..
Dialing to temp to 220 works great of coarse and the print had a more cleaner outside with less 'blobs' then before.

Thank you for the feedback, that is very interesting results indeed!
I might have observed this effect myself too now when I think about it, but I just was not aware of that the ruby might affect the transparency of the print.

[danilius]

I feel a bit bad having not posted my recent experiences with the ruby nozzle. First of all, I only printed one small test of carbon fibre filament with some unknown stuff, nothing to report there basically. It printed, boring result. Was only a small test cube anyway.

Also, I seem to be getting to grips with the nozzle and with PETG it looks like I can stay at around 240C - 250C and still get good results. PETG is anyway proving to be a bit of a pain, my earlier prints were far simpler than I am attempting now, and so the ruby nozzle actually helps in narrowing down setting for a better surface.

All in all, for regular printing the ruby nozzle produces "sharper" prints in that the nozzle geometry helps to highlight problems with the print, but the ruby surface itself does not seem to be more or less sticky than brass for any material I have tried so far, so for regular printing does not provide any particular benefits or real disadvantages.

On the cool factor side, it of course can't be beaten

[danilius]

Finally had time to mount the ruby nozzle to my UM2Go, because I am using my UMO's with a 0.8 nozzle for bigger prints these days.
And there is a noticeable difference!
Printing in rPET the material is much more translucent compared to the brass nozzle and I could print cooler.....
Because of the material presets in the UM2Go I sometimes forget to change the material before, so the PET starts with the 210 degrees preset. With the brass nozzle the print would be white and start to suffer from the low temp, but the ruby nozzle would finish the print translucent with no problem..
Dialing to temp to 220 works great of coarse and the print had a more cleaner outside with less 'blobs' then before.
2016-05-23 09.02.59.jpg
2016-05-23 09.05.06.jpg

What I think you will find is the ruby version has much more air in the layers, which means that you have lower interlayer adhesion. The air refracts the light which makes the print shinier, which is a nice effect, but mechanically poorer.

[LePaul]

More air? Please explain...that's interesting

[danilius]

More air? Please explain...that's interesting

I have printed several kilos of PETG with the gorgeous ruby nozzle as well as standard 0.4mm nozzles, and with a 0.8mm nozzle. After faffing around a lot with various temps and speeds, I discovered by watching the nozzle when printing that if uneven - essentially underextruded - lines were drawn, such as after a long retract, when the next lines were drawn over them they looked quite different than layers with better adhesion, i.e. properly drawn lines.

So I set things up to exaggerate the problem, such as using the new coasting feature, and this appears to confirm my theory. The refractive properties of PETG exaggerate this effect, but it can be seen in hot nylon (such as Taulman Bridge) as well. Air of course has quite a different refractive index than PETG. So when you trap it inside the plastic, you get that silvery sheen effect. PETG has an incredible property in that when you have your lines being drawn very flat on top, i.e. well squished down, the layers fuse into a solid. I think it's because PETG retains heat far longer than other more common plastics. So when the next line gets drawn, the layer below fuses really well.

Having smashed quite a few pieces in the name of.....OK, it was fun....I discovered that the broken pieces had shattered as if they had been injected. The broken surface did not look like it was printed out of layers. There were no layers to be seen. It's quite bizarre, but probably something that contributes towards the incredible strength of PETG.

[Dim3nsioneer]

Btw: Is there or has someone tested a ruby nozzle with an opening larger than 0.4mm? IIrc Woodfill is also quite abrasive and I print it with a 0.8mm nozzle...

[LePaul]

A ruby toothpaste nozzle would be neat to see!

[Meduza]

I belive there is none so far, since the ruby manufacturers have quite high minimum orders and long lead times the focus is on getting everything working really well in 0.4 before progressing to anything else.

[danilius]

Currently I am printing various prototypes with a 1.0mm nozzle, and it's incredible to see how fast that goes. Oh, and they are interlocking and fully functional prototypes just in case you were wondering. With some careful planning printing with a 1.0mm nozzle is really a fantastic way to print large parts and still get a respectable surface finish. Ruby toothpaste nozzle, yay!

[martin-bienz]

I have now printed 4 roles (125m Diamond Age) of PLA (and a few NinjaFlex prints). The Ruby still holds perfectly well, no visible issues. All great (top surface could be better). No special filaments so far...

[martin-bienz]

Currently I am printing various prototypes with a 1.0mm nozzle, and it's incredible to see how fast that goes. Oh, and they are interlocking and fully functional prototypes just in case you were wondering. With some careful planning printing with a 1.0mm nozzle is really a fantastic way to print large parts and still get a respectable surface finish. Ruby toothpaste nozzle, yay!

Question, how is the oozing with the 1mm nozzle? I am still to test it and I have now an application . Can you please upload a picture of the finish? Can you also say something with regards to tolerances etc, do I need more? Thanks!