Can organic supports be based on the model instead of the build plate?
I have a design with a critical overhang pretty high up in the model. Ideally I would want to support this with organic supports which start on an uncritical surface of the model itself. I.e. a surface that will be invisible in the final assembly, and which is located a bit lower than the critical overhang.
But PrusaSlicer always bases its organic supports on the build plate, resulting in massive support trees which take a lot of time and material to print. Is there a way to force the starting point/area for organic supports to be somewhere on the model instead?
(I can't use snug supports since the overhang is displaced laterally vs. the desired support base surface -- so I need organic supports which grow sideways a bit. As a workaround, I have tried adding a slanted "floating slab" to my model, supported by snug supports from below and providing a base for snug supports below the overhang. This gives the desired result in the slicer, but has proven unstable in printing: The floating slab is prone to come loose, and then the print head crashes into it. So I would much prefer a simpler solution with organic supports only.)
RE: Can organic supports be based on the model instead of the build plate?
I barely use any of the Prusa supports anymore, I do all of my design in fusion and creating custom supports is pretty trivial. then when slicing I just print with 1 perimeter, sometimes 0% infill, sometimes 5/10% depending on the size of the support.
You get so much more control of the support this way.
RE: Can organic supports be based on the model instead of the build plate?
I barely use any of the Prusa supports anymore, I do all of my design in fusion and creating custom supports is pretty trivial. then when slicing I just print with 1 perimeter, sometimes 0% infill, sometimes 5/10% depending on the size of the support.
You get so much more control of the support this way.
How do you define the interface between your support and the model? Just a small gap? (How wide?)
Have you also used custom support structures which sits not on the build plate, but on a model surface? If so, how did you (loosely) connect those? My "floating slab" was essentially an attempt at such a custom support. But apparently it was not attached to the model firmly enough, so it could move upwards a bit, causing the toolhead to bump into it -- and then it was firm enough to cause a step loss...
Many thanks for sharing which interfaces work for you! I am using PLA at the moment.
RE: Can organic supports be based on the model instead of the build plate?
I barely use any of the Prusa supports anymore, I do all of my design in fusion and creating custom supports is pretty trivial. then when slicing I just print with 1 perimeter, sometimes 0% infill, sometimes 5/10% depending on the size of the support.
You get so much more control of the support this way.How do you define the interface between your support and the model? Just a small gap? (How wide?)
Have you also used custom support structures which sits not on the build plate, but on a model surface? If so, how did you (loosely) connect those? My "floating slab" was essentially an attempt at such a custom support. But apparently it was not attached to the model firmly enough, so it could move upwards a bit, causing the toolhead to bump into it -- and then it was firm enough to cause a step loss...
Many thanks for sharing which interfaces work for you! I am using PLA at the moment.
Yeah you can set the gap to whatever you like, exactly how you can with Prusa supports. I dont do this however, I always use zero gap, then apply a release agent on the top of the support.
On the parts I've designed I always manage to get a support grounded on the build plate, even if that means having the support at quite an angle. Of course the support will be thrown away, so the appearance of the support really isnt important, as long as its structurally sound enough to serve its purpose then its appearance doesnt matter.
RE: Can organic supports be based on the model instead of the build plate?
I've started to do the same but with a hybrid approach. I use FreeCAD to "draw in" break-away supports where I have a high over-hang and let the slicer manage the rest of it.
RE: Can organic supports be based on the model instead of the build plate?
Thank you both!
Looks like I will have to stick with my designed-in support slab, but find a better way to attach it to the model. If I move away from slicer-generated supports between the model and the slab, and replace them with solid (but breakable) connections, that will hopefully do the trick. Then use slicer-generated supports between the slab and the overhang.
I really want to attach the support structure to the model, rather than on the build plate. The overhang is approx. 25 cm up in the air, and I can base the supports at~ 20 cm height. Starting them on the build plate instead adds an hour of print time.
Nice idea with the release agent! I can't use that in the present case since the to-be-supported structure is not horizontal, so there is no defined point in time when the support is complete. But will remember that for future use! What agent do you use?
RE: Can organic supports be based on the model instead of the build plate?
Thank you both!
Looks like I will have to stick with my designed-in support slab, but find a better way to attach it to the model. If I move away from slicer-generated supports between the model and the slab, and replace them with solid (but breakable) connections, that will hopefully do the trick. Then use slicer-generated supports between the slab and the overhang.
I really want to attach the support structure to the model, rather than on the build plate. The overhang is approx. 25 cm up in the air, and I can base the supports at~ 20 cm height. Starting them on the build plate instead adds an hour of print time.
Nice idea with the release agent! I can't use that in the present case since the to-be-supported structure is not horizontal, so there is no defined point in time when the support is complete. But will remember that for future use! What agent do you use?
I use marker pen mainly, I've dabbled with PVA glue diluted with IPA, but it's easier and less messy to just use marker pen.
RE:
A black Sharpie works well in my case. Looking forward to the INDX and multi-material supports so I can retire my Sharpie.
RE: Can organic supports be based on the model instead of the build plate?
Looking forward to the INDX and multi-material supports so I can retire my Sharpie.
Oh yes. 😊
Did I ever mention that, despite my conclusion that I don't want to be an early adopter again, I did eventually pre-order the Founders Edition on day 1? I need to work on my mental resolve...
RE: Can organic supports be based on the model instead of the build plate?
Looking forward to the INDX and multi-material supports so I can retire my Sharpie.
Oh yes. 😊
Did I ever mention that, despite my conclusion that I don't want to be an early adopter again, I did eventually pre-order the Founders Edition on day 1? I need to work on my mental resolve...
Yep, I picked up a severe case of FOMO and reached for the credit card. Was lucky, there were only 280 left when I ordered mine and then 15 minutes later there were none left. At the time I had a SnapMaker U1 on pre-order as well which I've since canceled. I'm not really into multi-color (maybe someday) so I'll start with the 4 toolhead kit.