Cura2.5 Spiralize multi material

[ultiarjan 1,223]

@smartavionics I think the new spiralize works very good..... except for multi material... strange moves...and blobs.

I guess the solution is to make sure the end/start positions of the 2 materials are connected, and preferably random chosen to hide them even better.

[burtoogle 516]

I have some thoughts as to what could be happening here. I do not have any experience with multi-materials so you need to help me understand how this print is constructed. Can you provide a project file? If not, can you please provide a description of what you have done?

Thanks

[ultiarjan 1,223]

Sure, I'll PM you a project file tonight.

[burtoogle 516]

I have worked on the spiralize code to fix what I think is the problem here but I need a sample to test it on as I don't have a multi-extruder machine or any experience with creating multi-extruder models. Can either the OP or someone else provide an example project, please?

[ultiarjan 1,223]

Can't you just use the simple sample project I PM'ed you?

I can make something different if you need something else.

If you need me to test print from your new code you can just PM me some gcode for UM3 .... Or if you have a Cura version with a possible fix I can also try it for you.

[burtoogle 516]

Hi, sorry, I am an idiot, I didn't see that you had already PM'd me the project. I hope to have some gcode for you to test before too long.

[burtoogle 516]

Please try this gcode. I haven't been able to test it but it looks (in the Cura and S3D viewers) a lot better than what was being produced before. Apologies in advance if it wastes your filament!

https://www.dropbox.com/s/ug9atvz5z0spn5c/UM3_SpiralMultiMaterial.zip?dl=0

[ultiarjan 1,223]

Don't have access to the S3D viewer atm, will have a look tonight, but in Cura the "spiral" looks incomplete....

[burtoogle 516]

Those gaps you see that are all aligned vertically are where the z-seam occurs. If you view using S3D, you won't see those gaps, it's a feature (some would argue a bug) of the Cura layer view that it doesn't fill those gaps. I have already mentioned this to a Cura developer and their view was that spiralize wasn't important enough to warrant fixing the layer view!

Edited March 30, 2017 by burtoogle

[ultiarjan 1,223]

The strange move is gone, so thats good, but the material transition is not the best, the strings on the side are easy to remove, but the blobs in front are difficult to nicely clean.

There was also extrusion from the "change position" to the print, on the skirt printing of the 2th material, causing a polluting blob on the first layer. As I don't have the project file I cant check your settings

[burtoogle 516]

Hi, thanks for trying that. Well, a little progress. The blobs where the colours change are a worry, I need to look into how Cura does the material change. The little threads that appear on the right are weird, does that ever happen when not using spiralize?

I have made some changes, please try this one and let me know if anything is better or worse.

https://www.dropbox.com/s/lnjym92z2xw0dt7/UM3_SpiralMultiMaterial_2.zip?raw=1

I haven't changed any settings, I just open your project.

I also want to check how it works with models that alter with height, can you send

me a project with a small curved vase and multiple materials, please?

Thanks again for the help.

[burtoogle 516]

Hello again, here's another to try, this time I turned off combing and now it z-hops when changing extruders. Maybe that will help.

https://www.dropbox.com/s/klknecj3f9ldggr/UM3_SpiralMultiMaterial_3.zip?raw=1

Please let me know if this is better/worse.

That's enough for me tonight, see you tomorrow?

[ultiarjan 1,223]

That's enough for me tonight, see you tomorrow?

 

I'll give it a try and make you a new testobject, but it will have to wait till saturday....

[burtoogle 516]

OK, I should have some time over the weekend to do more. I will be out most of Saturday daytime.

[ultiarjan 1,223]

ok, so the version 3 has pretty big blobs, but that should have been no surprise as they also show in S3D  

More weird is the sort of extra ridge....

[ultiarjan 1,223]

how about this as a test model? better? just sink it a bit in z to avoid printing the bottom part to save time...

http://www.thingiverse.com/thing:21773

[burtoogle 516]

Hi, thanks for the latest feedback.

The blobs in S3D mark where the retractions occur. If you turn off displaying retractions, they go away (on the screen, not from the plastic, unfortunately!) At the moment, I do not know why they are occurring. Do you see any blobs like that when you change material on non-spiralized prints?

The extra ridge does not show up on the S3D layer view so I am baffled by that as well.

The traffic cone would be interesting but I have no experience of creating multi-material prints. Could you please create a project containing a two-material cone and send it to me?

Thanks, Mark

[ultiarjan 1,223]

here's the project file

https://www.dropbox.com/s/1f8cwmjkuy0irwy/UM3_Traffic_Cone.curaproject.3mf.zip?dl=0

and the baseline Cura2.5beta;

the brim looks poor as the 2th "poop" got dragged into the print.......

[burtoogle 516]

Hi, I have worked out where the blobs are coming from. Because the prime tower is not enabled, after the nozzle switch, it's extruding 16mm of filament onto the print. Enabling the prime tower will solve that but then it fails miserably because it builds the prime tower the same height as the cone as so it goes off to the tower every layer!

I think that what it needs is for the prime tower to only have one layer for each nozzle switch and for the print head to go up/down in z between the top of the prime tower and the top of the print. I don't even know if that is possible so I am going to open a new issue so that the cura devs can ponder it. Edit: Just done that but I can already see a big problem in that if the model is tall then it's not going to be possible to print a low prime tower without the hot end or some part of the mechanism striking the taller model. This may well be an intractable problem!

Sorry, no solution for multi-extruder spirals for the moment.

Thanks again for the help.

Edited April 2, 2017 by burtoogle

[ultiarjan 1,223]

I think for spiralize a tower is indeed no option.

Maybe you can influence a bit how the material transition looks?

A little string is not so bad, as easy to remove, but a blob is bad.

[burtoogle 516]

A little string is not so bad, as easy to remove, but a blob is bad.

Yes, my thoughts exactly. So what I am currently thinking is that instead of printing a prime tower, it simply does the prime into thin air in the prime tower position and then moves to the spiral. I am working on doing that but currently can't find the right bit of code to alter (can you believe, it's all quite complicated, really!)

[burtoogle 516]

Hi, please try this gcode, it does the prime before moving back to the cone. You'll get some filament extruded into thin air but, hopefull, it will be easy to clean off.

https://www.dropbox.com/s/u0lyt16sn9v9uox/UM3_Traffic_Cone.zip?raw=1

[burtoogle 516]

That cone had a problem in that after priming and moving back to the model it would have paused while the hot end heated up to the extrusion temp. This latest test does the pause before the prime and move, it should be better.

https://www.dropbox.com/s/oy6n745fykyma2i/UM3_SpiralMultiMaterial_4.zip?raw=1

[ultiarjan 1,223]

Result of test 4 was rather poor unfortunately.... I'll show a picture later.

[burtoogle 516]

Sorry to hear that. What happened?