Hi, welcome here!The problem with that behavior is not Kisslicer, but the model. It is -as many models on thingiverse unfortunately- not manifold, or 'watertight'.
In general is a stl a bunch of triangles, each of the sides of that triangles has at least exactly share a side with another triangle. The complete model must be covered with triangles: that's what's called a 'watertight' model. Important as well: each triangle has an inside and outside: of course for a good stl, the triangles have to be oriented well: so the 'defined' inside of a triangle facing the inside of the model. There are more rules for it but that are the most important ones.
So when triangles are overlapping, or leaving a gap, or double, or insight out, it gives errors as you have seen.
I have checked it, but stl has some errors, therefore KS can't slice it ok as well.
Kisslicer is more picky regarding an error free stl then other slicers, first I disliked it, but changed my opinion. When providing an error free stl, there is a much more predictable result.
You can repair it in the free netfabb http://www.netfabb.com/downloadcenter.php?basic=1 , but that wasn't enough for this model. I have repaired it in a professional program for you and attached it.
You can try the free Meshmixer from AutoCad as well. It's not stable, but I had some descend results / repairs with it sometimes. But hey! It's free! http://www.123dapp.com/sandbox
I attached some screenshots of the repair program as well the comparison in KS of the behavior with stl's with errors.
Bart
a copy of PenskeGuys post on a similar topic:
Models from Thingiverse are often junk. Netfabb will usually not fix a model to perfection. Most times, it introduces more errors than it finds or fixes, if it fixes any.... or finds any. usually, the only "mesh fixer" that is reliable has a pulse, because it takes intelligence to make correct decisions on something as complex as a 3D model having a multitude of points and polygons. No free lunch.
You need a mesh modeler, a converter or importer that will convert the STL mesh into the modeler's native format. Then look at the Mesh Error Key that shows if KS identifies errors to point you to where on the geometry the problem lies. Find the issue on the model and remove the usually extraneous geometry by welding points, flipping polygons, closing holes where polys are missing, locate two polys that may or may not be coincident (exactly same shape in same location), etc. The model needs to be what is referred to as "water tight", or in the technical term: "manifold". If it isn't the slicer will not be able to figure out what is the inside and what is the outside and you get garbage that is the evidence of this confusion.
Many CAD applications will not produce manifold models, nor do they convert to STL meshes very well. That isn't their focus. They aren't mesh applications by nature. They will have lots of coincident points, 2-point polys, points not on a poly, points on only one poly, etc. STLs need to be fully triangulated. This means one poly having three, and only three, points describing its shape. When you see "Degenerate Tri" in the Mesh Error panel, this usually will lead you to a "tri" that has four points. Selecting two that are near each other and welding them will clear the problem.
Other than that, it's too long to go into here. Jump in and you'll catch the drift.