Using different layer thickness in one print

[caml 0]

Hi Guys!

I'm new to the forum so please be kind since I may ask some newbie questions

I am planning to buy a Ultimaker 2 printer but there's one question to keep me from doing it already. The question is if the Ultimaker 2 printer (however I think it's a software feature) can print with different layer thickness in one print?

I need to use it in rather, let's say, "commercial" purpose and what I need is getting high quality prints in quickest time possible. Therefore, I would like the printer to make the "filling" of the print as fast as possible (thick layer, fast printing) and then the outer surface to be as good as possible (thin layer, slow printing). Overall this probably would be much faster than setting the whole print for thin layer and slow printing.

Is that possible?

 

Regards,

Caml

 

[gr5 2,189]

It's really a slicer question and you can use many slicers with the UM. But most people use Cura and Cura allows a different speed for:

outer shell

inner shell

infill

For example if the shell is two passes you can have the outer (visible) shell print slower than the inner shell and you can have the infill also print faster.

But be aware that with a .4mm diameter nozzle (that sort of sets your XY resolution) it's hard to get a ton of plastic through that small a nozzle. It can print about 10 cubic mm per second at normal printing temperatures. For .1mm layers that is (10/.1/.4) about 250mm/sec. For .2mm layers it's 125mm/sec. And most people print at least 3X slower (3 cubic mm/sec).

You can drill out the nozzle to for example .8mm and loose some XY resolution but gain massively in print speed.

 

[caml 0]

That's useful, thanks! I don't think I will need to do that, firstly I should try out all the basic settings. Thanks for explaining the thing with Cura. Is there any other slicer that allows some other modifications of the print settings? I see that in Cura it's possible to change the outer layer printing speed but is it possible to change it's thickness? From, let's say, 0.06 to 0.02?

What is more, giving that there's only one surface I'm taking care of - the upper surface (the element is a button, everything else will be hidden), is it possible to print everything lower that this surface as quick as possible (not taking care of quality) and make only this one surface look good, printing it slow? There's an option for "Initial layer thickness" but Cura says it's not a good option for making it thicker than 0.3 mm.

 

[eldrick 65]

You can use other slicer programs:

- Slic3r (Open Source - free) allows you to set different layer thicknesses at different heights in the print. Very useful for making better-looking rounded tops on pieces.

- Kisslicer (free or $45 options) allows you to print infill every N- layers. Speeds up printing greatly without compromising strength much. This effectively allows you to use thin outer layers with thicker infill.

No slicer program does everything well. Cura is good, but lacks both of these functions.

 

[gr5 2,189]

You can't change layer height part way through a print with Cura. But you can change the speed part way. There is a plugin that comes bundled with cura called "tweak at Z" and you can print the bottom portion of your print at say 150mm/sec and then when you get to the visible parts slow it down to say 35mm/sec.

 

[yellowshark 153]

Hi Caml

I am in a similar position to you I think and have the same requirement, i.e. different layer resolutions during a print. Until reading this thread, I only knew of one Slicer that did this and that is Simplify3D. S3D costs USD150 – but you cannot easily get a trial download. This is further compromised for me by the fact that I have heard good and bad reports on it, basically too many bugs. I would dearly love to use it but a 3D guy I know very well and respect highly has warned me off it. I am just now trying to get a particular job and would dearly love to use different layer resolution to get my pricing down – and I am now very tempted to risk buying the software. In essence it may be a product to consider after a new released is provided, it that release is primarily fixing bugs – a bit like waiting for Windows SP1.

Now EldRick above says Slic3r will give different layer resolutions. I was a Slic3r user for some time but swapped to Cura several months ago and I was not aware that you could get different layer resolutions with Slic3r – maybe a new release has added this? So that is something to check out. I have found on most things I do that Slicr will give a much faster printing time than Cura – but I have always found its retraction to be poor compared with Cura. I am now starting to go back to Slicr for large items with simple geometry (i.e. where retraction is less of an issue) because my pricing can be reduced by 30-40% using Slic3r. And I will be checking their website once I have posted this !!

 

[yellowshark 153]

Ok got it now. The Slic3r layer height function is contained within the Plater tab. Unfortunately I have never used this as it is useless; you cannot rotate around the z-axis and you do not get a 3D view of the model. I always load and position my model with Repetier Host if using Slic3r or direct in Cura if using Cura. I am guessing I might be able to orientate my model as I want it in Meshmixer and then export the STL file to Slic3r but that is a bit of a pain.

Also just being able to change the layer height, without changing print speed and/or extruder temp. is not ideal, if not calamitous. That is what is nice in principle about Simplify3d - you can just about assign any setting to a layer range. Of course you should be able to change your print speed and extruder temp via the printer controls and indeed using the pause button too would enable the extruder temp to change and stabilise. Cannot recall if you can do this in Cura, you can in Slic3r, but if you print infill before perimeters this should allow the extruder pressure to stabilise before printing the perimeter walls.

 

[yellowshark 153]

Sorry the above should read (... you can only rotate around the Z-axis)

 

[eldrick 65]

I find that the easiest way to reorient a part if you need to before using Slic3r is to open it with (free) netfabb Basic, where you can scale and rotate it without losing any precision. The program also alerts you to problems with the .stl file, and can repair many issues before printing.

Every slicer has a different combination of features, and none of them can do everything I'd like. Cura isn't superior to any of the others, but at least it does fan-speed control properly.

 

[yellowshark 153]

Thanks for that for that EldRick. I guess I am just lazy and like to do things in one place ; like you do in Cura or in Repetier Host that has an auto link to Slic3r and Kisslicer. I will admit that if you are just doing this occasionally then it would be no big deal to jump across to something like Netfabb.

 

[jameshs 42]

I have just started using Simplify3D this week so am a real newbie - but bought it to control the zscar as for a particular order I needed to be able to randomise the zheight change.

For £80 ish it resolved that problem.

up unti now (nearly a year) I have been very happy with Cura and will us it on the other prints that I have as it has a really good compromise between speed, complexity and simplicity.

But my early use of S3D has not been buggy - just a learning curve.

I am also using the ability to vary the temp to go faster in the middle but slower and cooler around bridging.

James

 

[eldrick 65]

If "the zscar" you refer to is the vertical line of layer start points that Cura creates because it does not bother to try to randomize or hide start points, you should try Kisslicer - it gives you Much better control over start points than any other slicer. It places start points at corners, and also allows you to restrict random start points within a range of specified angles around the periphery.

 

[yellowshark 153]

Glad to hear you are getting good results James. I have checked and see that there have been several releases since I last looked so it may well be that S3D is lot more stable now.