Portions of 3D model are missing when sliced, but visible in preview

[SeattleDavid 0]

I have a 3D model that isn't slicing correctly. The problem shows up in both Cura and Slic3r.

When being previewed in both slicers it looks correct, and it is complete.

But when I look at the slices, portions of the model are entirely missing. Both Cura and Slic3r do the same thing.

The model is of a stair/ladder, and what is missing are the handrails and other parts. (in the photos below, notice the lack of hand railing for the ladder.)

Here is the STL model as it appears in Cura:

Here is the model when it is sliced (showing support material.) Notice the lack of handrails.

This is the STL model in Slic3r:

Again, the railing is missing when sliced:

Edited September 25, 2016 by Guest

[Labern 763]

Check x ray mode to see if there are errors with the model shown in red.

What is the diameter of the hand rail?

And what sized nozzle are you using? A 0.4 diameter cylinder won't be sliced if you use a 0.4 mm nozzle, the cylinder needs to be slightly larger, like 0.45.

So set your nozzle size to a smaller size and see if it works.

[reemaj3D 1]

I suppose there's an error in the STL file, have you checked and repaired the file? https://makeprintable.com/ is a good free tool for this.

[jambalyle 2]

Netfabb is also a really good free tool for inspecting / measuring / fixing STL's.

My guess is that your part is just too thin. Try scaling it up and seeing if it shows up in the sliced views.

[geert_2 435]

Even if you would succeed in printing this in one shot, it is likely to break when removing the supports, due to the very thin items, and since they are printed in the "wrong" direction, not along the layers (like wood cut in the wrong direction, instead of along the direction of the fibers, is also very brittle).

If you can edit the model, it might be worth trying to split it up in several parts: railings apart, stairs apart, etc... And then print each part flat on the bed, without supports, and glue them together. Like the model railroad houses we built as kids. This would cost you less material, less printing time, and probably look better and be stronger.