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Hollow ring model prints solid

Can someone help printing a tapered ring. If I model it with tinkercad it prints correctly “hollow”. But tinkercad models are not very acurate circles.
If I model with Fusion 360 or Onshape cad it prints as a solid mass.

Picture. “Tapered Ring” could mean a lot of different things…

I am new to this
smallfiltertest10mm12mm2mmwall.stl (70.4 KB)
File attached.

So you don’t want this to be a solid, you want it to be hollow inside? What wall thickness?

Try feeding your STL in to MeshMixer and use the “hollow” function that’s there.

Note, if the inside is hollow the model will need holes to allow resin trapped inside during printing process to escape. I did not make any holes in this model.

What I did was take a cross section of your ring, and then I tunneled out the center of the cross section so it looked like this (note, made no attempt to get the walls all 2mm thick). The black wireframe is your original model file, displayed in the background for the sake of clarity on what I did.

Then I lathed it 360º to get back to the full object. Note, I made all the polys one sided and then flipped them all so you could see inside.

And here it is!

smallfiltertest10mm12mm2mmwall Hollow.stl (200.1 KB)

So I printed this and it comes out as a solid puck. Wall thickness was 2mm.
I just need the inside to be a simple ring with solid walls.

I am not explaining this very well. It is to be a ring with 2mm thick sides and taper. Very simple. I am new to resin printing I have been using Ultimaker for a few years.

[IGNORE THIS POST :slight_smile: ]

Check the STL I attached to my post, above. It’s not perfectly 2mm wall thicknesses because I was just trying to bang something out quick. But the methodology I describe will work.

Make a rectangle that’s the size of the cross section of your ring. Then make another rectangle that’s 2mm smaller on X and Y. Then use your CAD program’s CSG functionality to tunnel out the larger rectangle using the smaller rectangle. Then rotate the rectangle for the angle you want for the ring. Then move the rectangle away from the origin point by whatever you want the radius to be. Then use the CAD program’s LATHE function to rotate the rectangle around 0,0,0 a full 360º and you’re basically done. Then, punch a few holes from the outside all the way through to the inside so Resin can drain. Then print!

Ah. Now I understand.

There is something wrong with your original geometry. When I pulled it in to MeshMixer and tried to hollow it, MeshMixer generated a big “plug” in the center.

Here’s your geometry fixed.

smallfiltertest10mm12mm2mmwall Not Hollow.stl (100.1 KB)

Strange I have modeled adapters similar to this and FDM printed with no issues.
I did check it in meshmixer and it looked fine. Also looked fine in Preform.

Thanks for your help.

I printed your file and it was fine, so it is my modeling for sure!

I looked at your model again, too. It appeared fine when I pulled it in to one of my modeling programs. It appeared fine when I pulled it in to MeshMixer. But when I asked MeshMixer to hollow it out, I ended up with a big solid blob filling in the center. Of course, that hollowing operation isn’t what you were asking for, but I think it exposed the issue - there’s something in the middle but it’s not visible. Which is weird since I looked at it in Wireframe and it should have been, there.

Was easy enough to replicate your dingus once I realized the angle of the taper was exactly 10º. :slight_smile: