stl designs

[Bill George]

I found that Fusion 360 with a add in, can create files for lasers.... but I don't think that is what he wanted. I did not think STL files could be edited.

[Glen Monaghan]

I did not think STL files could be edited.

Originally, STL file format came from 3D CAD software as a means of representing simplified (approximated) 3D surfaces. I have no idea whether any software uses STL as its native format but it isn't common because it is only a polygonal approximation of a surface (much as a hexagon or octagon are polygonal approximations of a circle). Because they are only approximations, you lose the original shape when all you have are the polygons. Regardless of internal model description, most 3D software can export STL because it is a pretty simple format, a lowest common denominator for 3D shape description. You certainly can edit STL files because all you are doing is changing the polygon numbers, shapes, and orientations... but it's far easier to change the original surface shape (again, as a 2D example, change a circle's diameter or elongate the circle into an ellipse) and then recompute a polygonal approximation than it is to renumber/resize/reshape/reorient/realign scads (a technical term indicating it's significantly more than a bunch;^) of triangles, keeping the model manifold (water tight) in the process.

[Kevin L. Waldron]

test gray scale.jpg Example of what your looking for........ originally an STL .. converted to greyscale tif then to a JPG.........

You need to do your homework!!!!!! In the realty of things 3D laser work is a joke considering the time it takes to produce a quality item......... even a 6" x 6" of this flower is probably in the 4-5 hour range on the swiftest of machines.

I hold to my original statement....... STL's don't make the best CNC files......... because of the polygonal, triangular shapes and the way the gcode is run.

[Bill George]

Hmm here I thought the STL was just a approximate image and the actual CNC gcode was created from the vectors and geometry information contained within. BTW I am not Ron the OP and but it seems like a big time waster.

[Art Mann]

I regard .stl files as being kind of like .pdf files. You can get and use them in quite detailed resolution but you really can't do much editing except changing relative size and aspect ratio. The grey scale image that Kevin posted is one type of CNC router "3-D" imagery in which the relative darkness of the image defines how deeply the cut is made. Sometimes, automatic conversion to this kind of representation of a 3-D image works and sometimes it doesn't.

[Ron Sleeman]

Kevin,you hit it on the noise about grayscale plus the time to do it. Trotec shows in one of there youtube uploads. it can be done. But then, I see they did not do the design. GantryCo did it for them...lol I guess I will just run the STL models on my new wood cnc 4 x 8 table...lol I want to thank everyone that comment on it.

Thanks Ron Sleeman