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How to extend raft to include support pillars?
Posted: Thu Jul 02, 2015 1:39 am
by mitchfx
I have a model with lots of suspended overhang which requires a large area of supports that adhere to the platform away from the base of the object. Getting the first support layers to adhere is very challenging so it would be nice to be able to extend a raft underneath the towers. Unfortunately it seems like S3D ignores the supports when calculating the raft. Is there any way to force this?
Thanks.
Re: How to extend raft to include support pillars?
Posted: Thu Jul 02, 2015 5:59 am
by JoeJ
If you include a raft with support material enabled, the raft already expands so that it is below the entire model. Anywhere where you have support material supporting your part should already have a raft below it. You can also increase the raft offset if you need a few more millimeters around the edges if you have lots of support material.
Re: How to extend raft to include support pillars?
Posted: Thu Jul 02, 2015 9:23 am
by mitchfx
I figured out the issue. The problem occurs when you have multiple processes enabled with first one ending at a height before the support contact the model. I want to have a denser infill on the bottom of my print for balance/stability reasons, thus have split it into two processes that get merged during slice.
Is there a way to force the raft to expand to surround the supports when using this approach? The supports contact the platform in the first process, but I guess they expansion isn't triggered until it detects contact with the model?
Another possible "bug" is that the skirt/brim never seems to expand to surround the supports even in a single process UNLESS you have a raft enabled. It would be good to have a checkbox for this. As it behaves now you end up with a brim that goes only partially underneath the supports near the perimeter of the model's base. It seems a bit odd that the pillars get printed on top of that but not consistently...only where they happen to overlap. I would suspect that can cause inconsistent support first layer adhesion and possible leveling differences.
Re: How to extend raft to include support pillars?
Posted: Thu Jul 02, 2015 9:30 am
by mitchfx
Screenshot of what I'm getting with raft and multiple processes...
Re: How to extend raft to include support pillars?
Posted: Thu Jul 02, 2015 12:15 pm
by billyd
+1 I would like to see a way to manually control raft size in X and Y since S3D sometimes doesn't create the raft large enough in certain special circumstances.
Re: How to extend raft to include support pillars?
Posted: Thu Jul 02, 2015 11:27 pm
by mitchfx
So I'm assuming there isn't a workaround for this in the current version?
Re: How to extend raft to include support pillars?
Posted: Sat Jul 04, 2015 7:31 am
by JoeJ
Is this actually one single model that you are applying 2 processes to? I just tested that with a few parts I have and it still worked fine. But perhaps you have a different configuration.
It might be easier to help if you could just post your factory file

Re: How to extend raft to include support pillars?
Posted: Sat Jul 04, 2015 9:15 am
by mitchfx
Yes it is one single part. The STL is rather huge and also an object that cannot be shared. I will try to recreate the issue with a lower res proxy and upload.
Re: How to extend raft to include support pillars?
Posted: Sun Jul 05, 2015 11:47 am
by mitchfx
Here is the problem factory file with decimated model. No matter if I set the "TOP" process to have raft enabled or disabled (what is the proper option here?) , the raft is only built around and below where the model touches the platform. It never seems to respect where the supports are.
Re: How to extend raft to include support pillars?
Posted: Tue Jul 07, 2015 9:39 am
by mitchfx
JoeJ,
Did you get a chance to check out the factory file I uploaded?
Thanks.