slicer support question

I'm trying to design a stage fixture for a bullet comparison forensic microscope. I sure would appreciate a suggestion on what support method I should use on this simple part. I've rarely used supports, so I'm clueless. I'll be printing in PLA using Simplify3D. The TOP of the groove in the orange model is my concern. I need the slot as smooth as possible.

Thanks in advance ...

 

Have you considered to print this with the slot upwards and supports under the arch? It will change the layer lines but for your intended purpose, I don't think the strength difference will matter. You'll get aliasing from the horizontal layers, but could minimize that with 0.100 mm layers.

 

No, I haven't considered that. It needs to be smooth on both sides.

 

As smooth as possible may be a compromise between support bumps and impossible printing. Consider also to take a shot at slicing it in PrusaSlicer, as the support algorithms for that slicer seem to be cleaner than S3D, which I use as well.

 

... thanks for the input. I'll rethink the design.

 

I thought of something else that might be helpful to your design. Angus (can't remember his YouTube channel!) suggested to add in non-supports that serve the purpose. In the case of the part laying on its side, if your skills permit, consider a single wall thickness truncated cone that extends from the outer edge of the upper lip just clearing the lower one and ending on the build plate. It might be necessary to have two walls if your printer clutches at a single wall, but it's sort of like vase mode and by being curved, provides its own stability.

This would turn the upper overhang into a bridge and probably give the best results. It would have to be broken or cut away, leaving a minor flaw to be post-processed.

 

Obviously not to scale, but the attached image shows the bridging option if you add a skirt-type to the model.