MMU2 with other nozzle sizes ?  

Re: MMU2 with other nozzle sizes ?

There is a problem with smaller nozzles in that the ramming speed required to prevent stringing may be difficult (impossible) to achieve.

It's the same situation with lower layer heights. I just about managed tool changes at 0.15 layers, but anything less failed.

Larger nozzles should work, but potentially there's not much gain with the maximum melt volume of the V6.

Peter

Re: MMU2 with other nozzle sizes ?

I did have some success in printing with a 0.25mm nozzle, but I haven't attempted prints with large numbers of toolchanges and the smaller nozzle.

I can't offer much more advice, since the models I printed had only a few dozen toolchanges and I didn't spend much time tuning my settings. But it's probably worth at least attempting if you want to spend some time tweaking things.

I'm cautiously optimistic that the MMU2S will be more forgiving of strings and other ramming problems, so it may be more practical once you install the upgrade.

Re: MMU2 with other nozzle sizes ?

the MMU2S will be more forgiving of strings and other ramming problems

So far, I haven't found that to be the case. Yes, in theory it will because you will get "Attention" rather than a fail, but for me it hasn't worked out quite that way so far 🙁

Peter

Re: MMU2 with other nozzle sizes ?

I printed the whole last week with a 0.25 nozzle and 0.1 layer height. No problems whatsoever.

Re: MMU2 with other nozzle sizes ?

I would love to know this as well....I usually run a .6mm nozzle to get faster printing for larger layer heights, and was wondering if there was a technical reason why .6mm nozzle was not offered as a choice for MMU2?

I thought there might be a reason about physically moving the filament at the faster speeds through the MMU2 assembly, that a .6mm nozzle would create?

Re: MMU2 with other nozzle sizes ?

I did a test just for fun a week back with a .6 nozzle with .3 or .35 layer height. I was surprised it worked to be honest. Didn't stop once asking for help.

Re: MMU2 with other nozzle sizes ?

Bigger nozzle size shouldn't be a problem. Smaller sizes are difficult already without MMU unit.
With proper configuration and calibration it should be doable with regular PLA. You might also need to adjust the purge tower to make sure all the bridges are really printing as expected.

Re: MMU2 with other nozzle sizes ?

This thread is rather depressing to me. I already tend to print .1 and lower layer heights and I've also played with a .25 nozzle for really fine prints. A major project I'm planning on (and ordered the printer and MMU for) I was planning to do at 0.05 x 0.25.

If this is really not doable, maybe I just need to cancel my order until finer detail is possible 🙁

Re: MMU2 with other nozzle sizes ?

This thread is rather depressing to me. I already tend to print .1 and lower layer heights and I've also played with a .25 nozzle for really fine prints. A major project I'm planning on (and ordered the printer and MMU for) I was planning to do at 0.05 x 0.25.

If this is really not doable, maybe I just need to cancel my order until finer detail is possible 🙁

For your purpose I think FDM printing is not really best solution. You could print that low but as already mentioned it require a perfect calibration. On a prusa printer you need to do this by your own. It will also require calibration for all filaments you're using separately.
Maybe SLA would be a better solution?

Re: MMU2 with other nozzle sizes ?

This thread is rather depressing to me. I already tend to print .1 and lower layer heights and I've also played with a .25 nozzle for really fine prints. A major project I'm planning on (and ordered the printer and MMU for) I was planning to do at 0.05 x 0.25.

If this is really not doable, maybe I just need to cancel my order until finer detail is possible 🙁

For your purpose I think FDM printing is not really best solution. You could print that low but as already mentioned it require a perfect calibration. On a prusa printer you need to do this by your own. It will also require calibration for all filaments you're using separately.
Maybe SLA would be a better solution?

Not sure why you say this. So far using default settings (other than changing infill to Gyroid) the MK3 has done everything I've asked it to do really well. I could stand to tweak the settings a bit to cut down on the "hairs", but it's only really bad at 0.05 on the 0.4 nozzle (0.05 on the 0.25 is pretty clean). Time is the real pain.

SLA would given finer detail, but it has a lot of down sides. The big ones for me are the low print volumes for anything approaching affordable and the mess and waste of dealing with the solution. Multi color prints are also not really an option, but that's starting to look like it's not an option with FDM either for my intentions.

Re: MMU2 with other nozzle sizes ?

Not sure why you say this. So far using default settings (other than changing infill to Gyroid) the MK3 has done everything I've asked it to do really well. I could stand to tweak the settings a bit to cut down on the "hairs", but it's only really bad at 0.05 on the 0.4 nozzle (0.05 on the 0.25 is pretty clean). Time is the real pain.

I don't have much experience with very thin nozzles as I'm usual printing with 0.4 nozzle. The issue I see with 0.05/0.25 is as you already mentioned print speed and very little space for configuration variations. Temp, Extrusion, Filament everything need to be spot on. But for MMU setup you usually want some room to wiggle. Dropping the temp, maybe adding more extrusion to get better overlaps. Every Filament inconsistency killing you. That's not like it's not possible, it's just more pain then regular 0.2/0.4 FDM printing.

That's why I think if you really need high resolution, there are better options. And don't get me wrong. I'm glad to see if someone prove me wrong on this.