Simplify3D Line between processess

[Tim_bc 2]

Now, I know this seems stupid and should be obvious, but apparently not for me

I'm printing a case for a Reach RTK Module, and the print is really straight forward.... Well, at least I thought it was...

I separated the print into two processes. I consistently have a line show up where the two processes change over.

I've adjusted the second process to have 1 base layer, 1 top layer and the finish seems good, but I always have a line show up right where the two processes change over. I have the 2nd process printing at 100%. I've tried different resolutions, and slicers. Cura handles this horribly unfortunately.

Clearly, I'm missing something here, anyone with better experience able to comment on the link provided? Any help would be really appreciated!

Thanks,

Tim

https://drive.google.com/drive/folders/0ByQ6OKsy-cVCaVFFMDJIR2xjQ2M

[neotko 1,417]

I will open the file later but I bet that your second process has a different 'first layer height' than the first process.

If this it's the problem you can see it on his gcode preview, rotate the camera zoom and look at the height of the second process first lines.

Edited August 27, 2016 by Guest

[Tim_bc 2]

I will check this first thing in the morning!

Thanks for the insight, hopefully this is it

[geert_2 557]

Similar visible deformation could also occur when the layer surface to print brutally changes from very big to small. Thus when the part suddenly gets a lot smaller (with a step, not gradually). This gives very different layer cooling times for the big surface and then the small surface. The small surface may not have enough time to cool, and thus deform. This often gives similar lines too in my prints at such changes in print layer area.

[Tim_bc 2]

Similar visible deformation could also occur when the layer surface to print brutally changes from very big to small. Thus when the part suddenly gets a lot smaller (with a step, not gradually). This gives very different layer cooling times for the big surface and then the small surface. The small surface may not have enough time to cool, and thus deform. This often gives similar lines too in my prints at such changes in print layer area.

 

I never actually considered this to be honest. I'll have to spend some time trying to create a more gradual transition and see the results.

That being said, I've done 100 micron to 40 micron transitions countless times with never having an issue, but certainly something to consider.

Thanks for the input!

[geert_2 557]

Just to make sure: it's not about layer thickness, but about layer surface. (I use Cura 14.09, where all layers have the same thickness, except the first one.)

If I have a model which has - at a given point during printing - a surface area of 10cm2 on let's say layer nr. 86, and then that surface area suddenly changes to only 1cm2 on layer 87, then that big change in surface area will be visible on the side walls. It causes a "thick line" on the side.

On models where this is an issue, I usually print multiple parts at the same time (so each layer gets enough cooling time to almost environment temperature), or I print a dummy block next to it.

I have also tried designing a small "complementary dummy model" to print together with the real model. This complementary model would have the opposite shape, a sort of negative, so that each layer would get exactly the same surface area. But that was way too much work and wasted too much material. So that was a once-only thing, without conclusive results.