Best Support Settings in Cura for Ease of Removing?

[BumbleDuck 0]

Hey all,

I've got an ultimaker 3 that I've been attempting to print some pieces with Cura that have fairly large open areas that I think need support. I have a few questions regarding this. I love the dissolvable support but am just talking about supports with the same PLA as printed for this post which I'm interested in also printing quality prints in because its cheaper and faster to print.  

Why do some sides print with the selected support pattern like "lines" shown in the photo below?

While other sides of the SAME print I have selected lines on utilize this more solid (but not concentric, much flimsier) support as shown below?

Is the "lines" pattern harder on the printer than others due to the frequent stopping and starting?

Why does my print string out at the top but the bottom and middle layers are supported and solid as shown below? Almost like the top layers don't follow the circular pattern because they aren't lying on anything circular and just go point to point. But the lower layers don't have this problem. I've tried increasing the horizontal support but that also makes the support layers harder to remove which is a problem as well due to the delicate nature of the prints.

And although I don't want the stringing to occur because it messes up the finish of the overhanging layer, if it doesn't string out, it is also almost impossible to remove because there's no gaps that you can kind of see in the image below.

I had been using a support roof because I thought the solid layer would lead to a cleaner print line on the printed layer I want to keep, but I'm wondering if that's making it too tough to remove from delicate places.

Essentially the main connective theme of this post is what support settings in Cura have people found to be the best for producing clean prints and being easy to remove? What pattern, density, support roof, XY distance etc?

I would greatly appreciate it because waiting hours for a print to finish only to have these issues is driving me crazy!

And while were at it is it possible to search the forums? I've googled and looked for an answer I promise! I've only found official ultimaker results using the search tool at the top, nothing from the forums.

Thank you!

Edited December 6, 2016 by Guest

[gr5 2,173]

I've never been 100% happy with cura support structures.  It's such a waste that you bought the um3 yet you are doing single filament - too bad you didn't get the UM2.

Well I don't have any great answers.  I'm reasonably happy with the cura 2.X pva support options but those don't apply here.

I would probably just put my own support in cad.  You don't need any support for the square parts that have bridging.  But for those L shaped holes you have to support the base of the L.  Just not the top of the L.  For cylindrical parts you really need support on both arcing walls.  I'd make a very very thin wall  that touches at the top in 5 or 6 spots.  A thin wall on the inner and outer edge of those bridging arcs.

Just to reiterate.  The printer bridges pretty well.  So if you print like a doorframe - you dont' need support at the top of the door.

If you print with PVA it will make the pva stick out of the part - by default 3mm "horizontal expansion" which is perfect for these prints.  The pva can have a smooth top surface for the PLA to lay down on top of and it will come out very nice.

Here is a great example of what I mean by arcing support walls - the red portions on the lower left.  This is a solidworks rendering.  In real life it's all printed as one STL file in one color and you easily break off those thin "red" walls.

Edited December 8, 2016 by Guest

[bagel-orb 61]

The support is probably printed with the zigzag pattern, which is designed to be like the lines pattern, but all lines are connected to other lines, making for better support while still being relatively easy to remove.

I've found that while the main part of zigzag or square support etc is easy to remove, there is some unremovable part still attached to the model. You get the best results using a support roof, but you need to tweak the z distance.

When a move is required from support to another piece of support, no retraction is performed which causes stringing. However these strings don't touch the model.

[neotko 1,417]

When a move is required from support to another piece of support, no retraction is performed which causes stringing. However these strings don't touch the model.

 

The downside in my experience with that kind of tricks is that when printing again there's a gap of filament from the dripping from a to b, making the support less structured (and resistant) and that leaves some areas of the support more fragile when head moves and smash the support over and over with the nozzle drip (that colds from a to b on the tip) making every pass of the support (line after line) like if a small hammer hits on the weakest place. That why I really stopped trusting Cura support structures. S3D forces retraction from a yo b on aupports (if the amount printed so allows it) and makes structutes more resistant (IMO).

Leaving random dripping to hit printed parts (specially thin one wall linea like supports) is ok if you print very slow (for me very slow is 30mm/s) but as soon you want to print faster you need to have all parameters under control. Ofc Grid is an option, but a hard to remove option.

Edited December 11, 2016 by Guest

[BumbleDuck 0]

I've never been 100% happy with cura support structures.  It's such a waste that you bought the um3 yet you are doing single filament - too bad you didn't get the UM2.

Well I don't have any great answers.  I'm reasonably happy with the cura 2.X pva support options but those don't apply here.

I would probably just put my own support in cad.  You don't need any support for the square parts that have bridging.  But for those L shaped holes you have to support the base of the L.  Just not the top of the L.  For cylindrical parts you really need support on both arcing walls.  I'd make a very very thin wall  that touches at the top in 5 or 6 spots.  A thin wall on the inner and outer edge of those bridging arcs.

Just to reiterate.  The printer bridges pretty well.  So if you print like a doorframe - you dont' need support at the top of the door.

If you print with PVA it will make the pva stick out of the part - by default 3mm "horizontal expansion" which is perfect for these prints.  The pva can have a smooth top surface for the PLA to lay down on top of and it will come out very nice.

Here is a great example of what I mean by arcing support walls - the red portions on the lower left.  This is a solidworks rendering.  In real life it's all printed as one STL file in one color and you easily break off those thin "red" walls.

 

Thank you! Good to know about the supports. I've been messing around with creating custom ones in Cad but you saved me a lot of time trying to find just right goldilocks supports that might not exist in Cura!

The PVA support is great and I'm using it with higher end materials for the same shapes. I'm a little bit bummed it doesn't print great just on top of Ultimaker PLA and you have to waste all of the expanded PVA though, at least in the tests I've tried.

[geert_2 557]

Similar to the image shown by GR5, usually I design all supports manually, and I optimise them for easy removal, good stability, and maximum accuracy of the model to print.

In reply to a similar question, I posted a few pics of support concepts that work well for me. See:

https://ultimaker.com/en/community/34784-best-settings-for-support-structures

[BumbleDuck 0]

Thanks Geert neotko and bagel. I've built custom supports. But my issue now is that Cura won't recognize some of them! Among many other issues I'm having with Cura...

This is what the file should look like. All of the supports are the same thickness and size.

However, when sliced some of the supports disappear. However, since some remain I don't think its a problem with the supports as they are all the same...

Any idea why this would occur?

With a different, slightly larger support structure the first few layers of the first two support doesn't exist according to the slicer, even though the regular model shows them and the latter two support structures are complete.

Another slicing issue I have is shown in the photo below, some of which I can get to print out with the full face while others, seemingly at random will remove the bottom of the ovals.

Also Cura "exploded" my model randomly as shown below even though all I did was duplicate the unexploded model to its left and lower the scale from 54 to 51mm.

And finally my printer/cura decided to randomly switch the print orientation about 3/4 of the way through a print. I couldn't find any record of this in the slicer layers but for some reason the rectangles that were being printed switched orientation. Based on how some started to try and print on thin air it looks like the entire file decided to do a 90 degree turn.

Are these bugs or are there settings I should be playing with? Based on my searches I learned about a "fix horrible" setting that might be autocorrecting things but I think that was only in old versions of Cura? Should I just reinstall Cura? Reset my printer...

This has been very frustrating as nearly model I have has an issue in Cura. They stl's are exported from blender, but on a different printer using repeteir host I have not had any of these issues.

Thank you!

Edited December 14, 2016 by Guest
added exploded base

[DaHai8 74]

If any support, or part of the support, is narrower (or equal) to your nozzle size, Cura will have difficulty slicing it (ie: it won't - reliably)

Try X-Ray view in Cura to see if there are any Red areas. These are issues with the model and can prevent it from slicing properly

[LePaul 321]

The zig zag support is a bit problematic for me, since I am printing medium to large size pieces that are curved. To reduce print time, I have oriented them vertically but still run into issues where the head nudges into the supports. Z hop helps some.

I've never really understood the differences between the support types offered in Cura. The info on the website was absent or vague

Re-doing the model isn't really an option for me.

[dwchristopher 0]

I haven't seen any mention in this conversation of the primer tower. For the UM3, the primer tower should be used any time that you're using PVA supports. This gives the nozzle adequate time to properly heat, as well as clear the extrusion opening. I highly recommend using a primer tower larger than 7x7mm. My shop (also a reseller) has had great successes with the PVA, as well as Cura's suggestions for placement. Also, there are a ton of settings in Cura that are initially invisible. You may find some answers in the additional settings, just be VERY careful about how quickly you change them!

Best of luck

[BumbleDuck 0]

If any support, or part of the support, is narrower (or equal) to your nozzle size, Cura will have difficulty slicing it (ie: it won't - reliably)

Try X-Ray view in Cura to see if there are any Red areas. These are issues with the model and can prevent it from slicing properly

 

I redid the supports and made them thicker and cura is recognizing them now. Just weird that for some it would slice properly while others it would not. But I guess as you said it's not as reliable.

Still have no idea what's happening in my last three models though haha

[geert_2 557]

That "recognising problem" is why I make my supports 0.5mm thick, to print with a 0.4mm nozzle. Indeed, if designed exactly 0.4mm, some supports may not be seen by Cura. I am not sure, but my guess is that it may have to do with the STL file: due to the STL-triangles instead of exact shapes of the original model, dimensions may get just a little bit smaller than 0.4mm. And then Cura won't print them (at least not my version 4.09).

[neotko 1,417]

Cura doesn't print anything thicker than x2 the width of the line width (or nozzle). Single lines walls on cura are only done by the supports. So, if you use a 0.4 nozzle (or line width), make the custom supports 0.8

[DaHai8 74]

Cura doesn't print anything thicker than x2 the width of the line width (or nozzle). Single lines walls on cura are only done by the supports. So, if you use a 0.4 nozzle (or line width), make the custom supports 0.8

 

No, this is incorrect. Specifying a .39mm nozzle (even though its .4mm) and printing a wall .4mm thick will work and it come out significantly less that .8mm. I already demonstrated this to you in this thread:

Cura 2.3 (same on 1.5.4) slicing / printing tapered edge issues

I'm surprised you're still pushing this.

Also, as geert_2 recommends, you can print .5mm object with a .4mm nozzle. And it does not thicken it to .8mm. I do this a lot with hot-end cooling ducts to reduce weight.

Try it yourself. Get some calipers and print some .4mm - .5mm walls.

[neotko 1,417]

 

Cura doesn't print anything thicker than x2 the width of the line width (or nozzle). Single lines walls on cura are only done by the supports. So, if you use a 0.4 nozzle (or line width), make the custom supports 0.8

 

No, this is incorrect. Specifying a .39mm nozzle (even though its .4mm) and printing a wall .4mm thick will work and it come out significantly less that .8mm. I already demonstrated this to you in this thread:

Cura 2.3 (same on 1.5.4) slicing / printing tapered edge issues

I'm surprised you're still pushing this.

Also, as geert_2 recommends, you can print .5mm object with a .4mm nozzle. And it does not thicken it to .8mm. I do this a lot with hot-end cooling ducts to reduce weight.

Try it yourself. Get some calipers and print some .4mm - .5mm walls.

 

What I mean is that it doesn't do a single wall. No just 'on' line. But a line that goes and comes back.

Indeed I know you can get stuff smaller, but is just not a single wall. That's what I mean.

Edit. I never saw your post, interesting. Still is two passes and for supports cura use one extrusion line.

For me when I want repetition and be sure about the size that will come I prefer to control the settings. For example printed a very thin wall bearing using 0.25 nozzle line width (with 0.4 nozzle) and I was getting a good 0.51ish wall size. So even when you get a simulation of the width you want is better IMO tonhave all under control and know exactly (as far as possible) of how the print part will be.

Edited December 15, 2016 by Guest

[geert_2 557]

@neotko: your observation that it is "not a single line, but doing a line and coming back" on a 0.5mm support is correct indeed. I have also noticed it. But it seems to be not a "full width" line. Probably with a lesser flow, to arrive at an estimated width of 0.5mm? Maybe one of the developers could tell how it is done exactly?

I use Cura 14.09, it may be different in other versions.

The advantage is that these 0.5mm double lines give a bit more strength than a single 0.4mm line support. And it guarantees that the support will always be printed, even if the STL is slightly inaccurate. So it saves me these worries.

[neotko 1,417]

True! That should be an advantage indeed. I would only worry if the patern isn't clear to the path planner, but that can be fixed trial/error.

About fine tunning the flow, I would use the new cura, since you could have the stl of the oject/support on two files, launch them to cura, merge to mix the x/y/z origins and then using the icon of Per Object settings you could fine tune the flow of the designed supports without affecting the rral print. New cura has some nice options to tune the print.

[gr5 2,173]

True! That should be an advantage indeed. I would only worry if the patern isn't clear to the path planner, but that can be fixed trial/error.

About fine tunning the flow, I would use the new cura, since you could have the stl of the oject/support on two files, launch them to cura, merge to mix the x/y/z origins and then using the icon of Per Object settings you could fine tune the flow of the designed supports without affecting the rral print. New cura has some nice options to tune the print.

 

Very cool idea! Yes you could tell Cura you have a .4mm nozzle (line width) for the model and .25 line width for the supports. You simply have to output the model and supports into two separate STL files.

[BMacCartney 0]

What are the settings for a easy snap off support in Cura 2.5?