PVA support issues

[Alex L 28]

Just got our lovely new Ultimaker 3 up and running and we are tying to print a massing model which has balconies, seems like the perfect use of the PVA support material but Cura does not want to support the balconies without placing PVA support almost everywhere as the attached images.

Is there some setting to stop it printing PVA where it is clearly not needed? 

 

[SandervG 1,204]

Hi @Alex L, Welcome to the Ultimaker community! 

 

You could try to reduce the horizontal expansion for support, it will make the support protrude less from your model. By default it is set at 3mm I think. 

Here is an example to show what I mean:

 

If you want to exclude some areas from getting support entirely, you could give the support blocker a chance. It is in our latest Ultimaker Cura Beta and it is fairly new so keep this in mind. It allows you to place blocks into your model, and the areas covered by this block don't get any support. By default the block is fairly big. If you want to make it smaller you should place 1 block on your model using the support blocker tool, select the scale tool and reduce the size. Using Move you can also move it around in all 3 dimensions. When your satisfied where it is placed, you can decide to add another block etc. 

 

Support blocker tool, Scale tool and Move tool can all be found on the left of your viewer. Highlighted below:

 

 

Hope this helps! 

 

By the way, you're printing an architectural model. Perhaps you find this Architecture category interesting to follow too. User @Stefania Dinea posts guides frequently, perhaps they're also useful for you, or your 2 cents could help someone else. If you want, you can follow it using the top right button. 

[Alex L 28]

Thanks @SandervG I'll try downloading the beta version of Cura and see what this does to the print times

[Stefania Dinea 97]

I can tell you for sure that those balconies are too thin in that scale to print properly and one part seems to be flying - but might be just the angle (I figured out it's an overhand - nvm). I would print every building separately and us the touch build-plate support function.  Looks good though - congrats on the UM3. 

 

Edited April 5, 2018 by Stefania Dinea

[Stefania Dinea 97]

However depends how many mm is the overhang in scale, might be able to print without support.

[SandervG 1,204]

No problem, let me know if it works! 

 

Here is the feedback thread for Cura 3.3 Beta. It has some more explanation re the support blocker, and you may want to leave your feedback too after using it. 

[Alex L 28]

Thanks for the reply @Stefania Dinea

Yeah it's just the angle the screen grab is taken at. Ideally the model would be amended to omit balconies at this scale but we are tying to do a comparison print against another office's Ultimaker original so have replicated their settings entirely (the balconies on their print are malformed blobs as is to be expected but we had hoped that with PVA the results might differ slightly

[Stefania Dinea 97]

Try a 0.25 nozzle and a very veeery small layer height - you will get better results - put the pva on 0.8 and don't drop the model in watter hotter than 35 degrees  Also use @SandervG setting recommendation.

Edited April 5, 2018 by Stefania Dinea

[Alex L 28]

All paused for now whilst we wait for approval from our insurers to run the printer out of office hours 

Will let you know how we get on once we are given the all clear!

[Stefania Dinea 97]

Aaaa .... you didn’t leave it running but you paused it when the bed keeps the 60 degrees temp while paused?! Hmm ... looking forward to see the results.

[Alex L 28]

Ah no, we never sent the cura file to the printer, all saved away, I should have said 'on hold' apologies for the confusion!

Edited April 5, 2018 by Alex L

[Alex L 28]

Ok, here it is! Printed over 22 hours using 'Fine' settings in Cura with no support just to see what would happen. Pretty pleased with the result, the balconies have ended up looking ok even when printing in thin air.

We will run one on fast soon to see how that changes everything.

Edited April 16, 2018 by Alex L

[Stefania Dinea 97]

@Alex L looks really good and 22 hours is a good time for that print. 

[kmanstudios 999]

If you are playing with the 3.3 beta, there is a bridging section added for just this type of thing.

 

Model does look good and 22 hours for that print? Wow....not too shabby

[future_engineer 0]

Hi Alex,

 

I would suggest that you use a smaller percentage of support with the selected extruder 2 (PVA). 

 

Try a small scale print first and then if you're happy with the quality, print it on large scale as I can see your print looks like a large one.

 

Thanks and goodluck

Nathan