TPU support structure issues - Support Z Distance

[Hendrik91 0]

Hi,

I use Ultimaker Cura and an Anycubic i3 Mega S 3D printer. I'm currently having trouble creating a decent support structure for TPU. I can print TPU just fine without support structure.

 

The problem is that I either can't remove the support structure or the layer above it looks very bad.

 

I've noticed now that the layers of the support structure are always as high as the rest of the print part. With a layer height of 0.3mm, it doesn't matter if I set the support Z-distance to 0.1mm or 0.3mm. In the preview, this distance is always 0.3mm, see the following image. I can't see any differences in the test prints with 0.1 to 0.3mm Z-distance either.

 

Is anyone able to help me?

 

[GregValiant 1,245]

TPU sticks to itself really well.  Your "Support Interface Density" of 100% is effectively just another layer.  You can try using something like 40% but the first layer above support doesn't get any "squish" and never looks as good as layers that go down on the bed or on top of other layers.

A hobby knife is your friend.

The "Support Z Distance" can only be exact multiples of your layer height.  If the Layer Height is 0.3 then your Z distance could be 0.0, 0.3, 0.6, 0.9, etc.  Cura cannot vary layer height during a print.

I usually use "Grid" linetype for the Support Interface and at densities ranging from 25% to 60% and .6 to 1mm  thick (depending on the model).

I limit my TPU printing to flat gaskets and some seals because it is so hard to clean up after printing.

I did some experimenting using a Pause at Height when the first layer above support was supposed to go down.  I had pieces of blue painters tape prepared and sprayed with hairspray.  At the pause I would put them over the support and the first layer above the support went down better.  It was more trouble than it was worth.