Slicing a model


#21

I understood everything you did, up until you retained the end face. What do you mean by a scaled up copy?


#22

I used the “Dave Method” and created a copy of the component with the cutting face inside it. That copy was scaled up. I usually scale up by a factor of 100 or 1000 because dimensions are easily converted when needed. I did that before making the GIF so the GIF shows working on the scaled copy. After completing the cutting and cleaning, the exit the edit mode for the component and delete it. Return to the original and it’ll show the same thing.

Although I rarely have need to 3D print my models, I have found that making and keeping components “solid” results in models that are easier to work with. A little cleanup on the original component (closing a couple of small faces and erasing some unneeded edges) resulted in a solid component.

Adding the cutting face, copying the component and scaling up the copy…

You could add the cutting face to the enlarged copy but it’s often easier to figure out where it needs to be placed on the original, full sized one.

After cutting and removing the unneeded bits and then deleting the large copy, the component has the face at the end and is still considered solid.


#23

Got it. I like the way the end gets closed off instead of just being left open. Thanks for taking the time to show me.


#24

I have a question about this: is the resulting end of the figure actually the area of the cutting face defined by the original shape left behind while the area of the cutting face outside the shape is what gets deleted? In other words what you might expect if you pushed the original shape into a plane like a cookie cutter makes a cookie shape? I ask this because it looks to me like the original shape does not have a closed end. If that’s the case you may not want to seal up the end. (Should be easy enough to delete, no?) And I think Dave said “keep the end” which made me think the original end slid into place where the new end should be after the cut.

Obviously not an issue of huge importance but I’m curious…glenn


#25

Glenn, I’m confused about what you’re asking. In my example, the new end face after intersecting the cutting plane and removing the waste is actually part of the original cutting plane. In the Intersect operation the cutting plane divided the faces of the fret board and the faces of the fret board divided the cutting plane.

The original fret board component is closed at the end although the end is made up of multiple faces.


#26

I went back and looked at slbaumgartners original answer to the first question and his animation clearly shows the fretboard as open ended when his cut is complete. Your (Dave’s) cut ends up with a closed end. Originally I assumed the cutting face was pierced like cookie dough and a cookie cutter and the interior part of the fretboard just didn’t get erased with the rest of it because it was on the other side of the line. But that isn’t what happened in the original case shown by slbaumgartner. Other than the scaling up, I wonder what is different that accounts for sealing up the end in one case and not the other. Not a big deal…

BTW, while we’re having this intimate discussion, would you be willing to share your loom stool drawing? I have a hankering to make one for my shop (for my back and rear end, actually). I’m sure I could figure it out but since you already have…
(Maybe someday I’ll get a loom, too)


#27

The reason it doesn’t close up in Steve’s example or the other ones shown is that there are some vertices that are very close together where those edges come off the hole for the mother of pearl inlay dot as well as at the rounded edges of the fret board. The proximity of the vertices runs afoul of SketchUp’s ability to create the short edges that are required by the face. I got around that by using the “Dave Method” and scaling up the copy of the component before running Intersect Faces.


#28

@DaveR is exactly correct. I just did a quick animation to show the idea without scaling first. If I use “the Dave method” I get a closed end too.


#29

And, to beat a dead horse, here’s a screen shot of the problem.


#30

Thank you both for that explanation. Now I have a little insight into that problem of small dimensions fouling up SketchUp and what to do about it. It’s a good thing…