Super hard nozzles - Test pilots

[Amedee]

Public holiday yesterday, so I took the opportunity to take the hot-end apart to do some cleanup after the leakage at the brass pipe side.

I mounted it now 'the other way around', that is first the brass pipe, then the nozzle tight against the pipe, leaving a small gap between the shoulder of the nozzle and the heater bloc.
This is definitely a better that way -- although it never happened to me, quite some people broke the brass pipe when tightening it and it is more easy to tighten the nozzle which an hex tool.

I have printed for 3-4 hours in this configuration, no leaks at all and I don't see an adverse effect on the temperature side.

The nozzle gives a very nice surface finish; top layers on a 20% infill are very nice as from the 3rd layer with the infamous Ultimaker blue PLA.

Apart from that I am still having crappy prints, nothing to do with the nozzle: I have a quite some play in the linear bearings generating some artifacts on the walls, and under-extrusion kicks-in from time to time
For the last one, I suspect a problem with the thermocouple: when the printer is idle temperature is very stable, but when the print starts temperature jumps in a +/- 5°C range. I suspect a bad contact somewhere, bur can't find it...

[Dim3nsioneer]

Repeated the overhang tests with PLA (two different brands) and found no quality difference between the 3dSolex brass nozzle and the Ruby nozzle.
Actually I would also like to the Ninjaflex but I'm not sure if I'll find the time as I'll be super busy for the next three weeks.

[Neotko]

Ruby indeed does good surfaces, the think it's that it softens less and hides a bit worse the errors (and thanks to that I was able to set my printer perfectly tuned), as I told anders on my many tests the think about the surface it's that it scratches more, for flat areas you won't notice much, but for complex flat layers with many movements there's a subtle difference. A test like this should help to see the subtle difference https://www.thingiverse.com/thing:704409 for normal objects it's just better, but for complex flat layers with small areas with zigzags, there's where you can notice a bit the effect.

[LePaul]

I'd love to see photos Amedee of what you went through to get the nozzle installed right

[Titus]

I'm too scared to remove the nozzle now I heard this

[Amedee]

I think it is more difficult to explain than just doing it

Bottom line: Anders's nozzle (and E3D) have the threaded part a little bit shorter than the UMO original nozzle. So if you just replace the original with the ruby one, you will tight it against the heater block, but there will be a little space between the nozzle and the brass pipe and it will leak at the top of the heater.

So you can just tight again the brass pipe (like you did when you built the machine), and go through this pain each time you swap nozzle, or just once and for good screw the brass pipe a little bit deeper in the bloc before mounting the nozzle, so your nozzle will be tight against the brass pipe and not the heater.
I'll take a picture tomorrow to show how it should be when mounted...

[Amedee]

Here it is...

Ruby 4 UMO

You can see now that there is a small gap between the nozzle shoulder and the block, so we are sure that the nozzle is tight against the brass pipe and will not leak!

[Neotko]

Amedee, that's how I did it long ago before moving to e3d forgood. But remind this, after the 6-7 change the aluminium screw will start to die leaving a half tilt alu block (it can be temporarily fixed) and at 15-20 the screw will just die leaving a dead alublock. Changing nozzles on umo has its problem at long term. Specially since you will need to tight the nozzle at 120C at least because the alu expands wuite a bit making a gap between the barrel/nozzle.

[Amedee]

Yes -- I don't swap nozzles very often, and as long as it does not leak, the thread remains nice. But indeed is is soft aluminum and you can go cross-thread easily.

before moving to e3d forgood.

What do you mean with that? Are you using E3d heating blocks?

[Neotko]

Nono, I mean e3d nozzles. I have a pt100 alu block from e3d but never used it.

[LePaul]

I finally had some time to remove the filament (ColorFabb Dutch Orange), remove the nozzle and install Anders.

As others have posted I have some questions along the way.

I heated up the printed head to 210C and then had it cool to 90C. I did a Atomic Pull on the filament and this is the result...looks really good but curious how it looks to others!

I just shut off the printer but gently removed the old nozzle while it was still hot. I'm a little curious about the residue?

I had printed Anders wrench a while ago and had everything ready to go!

Using vise grips to hold the block still, I gently worked the ruby nozzle into the heater block. Using Anders' wrench, I went until it clicked. I decided to go a tiny bit tighter using the socket wrench. Here's the results...it looks to be sitting quiet flush with the block.

As you can see I removed the fan shroud I had printed and just bolted the fan into place. If this looks "Ok" to everyone my next step was to do some light maintenance on the UMO (oil rods, tighten belts as needed and check pulleys). Then...on to trying out the Colorfabb XT-CF20 based on the settings others have had some luck with

[Neotko]

Lepaul, read what Amedee did, you have a leak because the barrel isn't touching the nozzle. Umo has a bigger head. Check the mm difference

[LePaul]

I don't have anything yet...I haven't dared use it yet

[LePaul]

Just to be sure I am clear at what you guys suggest...

1 Remove ruby nozzle
2 Use pliers to hold the PEEK and gently twist the brass pipe tighter?

3 re-install ruby nozzle, notice a small gap between heater block and nozzle?

[Titus]

The brass pipe should go a little further into the ALU BLOCK, not into the peek.
But yeah, main problems for me(haven't had more time yet) is the difference in height Neotkos image shows. Fanshrouds don't fit. Leveling was off, etc