Intersection of cylinder and plane

I have a question regarding working with circles that are push/pulled through planes. The cylinders created by the push-pull create ovals on the plane and I’d like to capture that oval. The problem that I’m having is that longitudinal segments of the cylinder tend to disappear requiring having to try to find what I’ve done wrong and try to fix it.

Have you tried using ‘Intersect Faces with: model or selection or context’, to obtain the ellips shape?

Draw cylinder and plane in the same context. I’ve drawn them as loose geometry in model space.

Select the round surface of the cylinder and the plane

R-click/Intersect faces/with selection (or with model).

That creates the ellipse. Delete what else you don’t want.

If you are having trouble because (for example) your cylinder(s) are components or groups, and the plane is outside them, cut the plane to clipboard, open the cylinder for editing, and use Edit/Paste in place to put the plane in the same context.

Alternatively, leave the plane outside the cylinder, open the cylinder for editing, select the round surface, then Intersect faces/with model. THat will create the ellipse in the context of the cylinder.

And if that still doesn’t work, upload your model here.

By the way, you need to edit your profile - Sketchup Make hasn’t existed since v2017. So you either have SU Make 2017, or Sketchup Pro 2018.

And is your operating system Windows 7, Windows 10, or some version of mac OS? You must be able to work out that at least.

If it’s a Mac, then click on the Apple icon top left, and then About this Mac. It will show you details of the version of the OS, and of the graphics card. Mine looks like this:

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I’m sorry to say that I haven’t. The bad news is that I’m not aware of how to find this feature.

OK, I’ve some work to do. First of all, I will beg your patience as I’m now too computer savy and also not well versed in Sketchup. First things first…I’ve looked for a way to edit my profile and haven’t been successful at that. Will you help me find it?
I’m using the SU make 2017 version, although I have downloaded the on line 2020 version, but haven’t used it yet, mostly because I don’t know how secure it is.

I’m using Windows 10

That’s helpful. Thanks.

To edit your profile, go to your avatar (a C in the purple circle) at the top right of your forum window. NOT the one beside your posts.

When you click on it you’ll see something like this (this is mine). I have a picture now, but used to have a white J in a red circle.

Click on your own name on the left. In the window that opens, click Preferences on the right, then Profile on the left, and complete or edit the fields there, then click the button Save Changes at the bottom.

Work your way down the page from About me to see the other fields and the Save Changes button.

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I’ve updated the profile with what I know. Ok, I’ve got a cylinder cut by a plane, and highlighted the result .
Now you said to r-click/intersect faces/with selection. I expected that the oval would be highlighted so that I could erase the plane and the portion of the cylinder that is not wanted. That didn’t happen

There it is !! I r-clicked w/the line tool on the intx of the plane/cylinder, and got the result I am looking for.
I believe that answered my question! Thank !you! Is there anyway that I can send a picture of what I’m modeling?

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It would be better to upload your Sketchup file - the one you are working on, with the file extension .skp.

Find it in Windows Explorere, then drag it into your next post, or click on the Upload button at the top of your post while you are writing it. It’s the 8th icon from the left, and looks like this: image

If you can’t see the file extensions, because they are hidden, unhide them by using Windows Explorer, go to View/Options:

In the Options window that opens, UNcheck Hide extensions for known file types

Hi, John McCleanahan,
Thanks again for your help and your patience. You solved my problem, and I appreciate your help.

You can R-click anywhere on a selected face, not just near the intersection.

You are always welcome to the help.

If my post was ‘the solution’ please mark it as such. (It was post number 3).

I know this post is alnostva year old, but I’m having trouble with this same thing. I am using the web based Sketchup version however. Is it possible to use intersecting faces with the web based version? My design is extremly simple, but the cylinders I a push/pulling intersect a no perpendicular surface so it won’t create the ellipse so I can remove the protruding cylinder piece and have a through hole.

Yes. Intersect Faces is available in the free web version.

Share the .skp file so we can see what you have set up and help you get it sorted.

Spacers 1.skp (194.1 KB)
Here is the progress so far. This is just an approximate prototype of what I am making to learn the skills and steps I need to design it with the correct dimensions. I was able to find and use the “intersecting” feature as you said and it fixed my original problem. My current problem is that I want to round the edges. I drew 3 arcs on the flat top side and pushed them trough as far as I could to the bottom, but they wouldn’t go all the way through because of the angle of the bottom. Any ideas?

Push/Pull stops when it hits the angled surface. Press and release Ctrl with Push/Pull to push beyond the angled face a bit. The select the geometry, right click and choose Intersect Faces>With Selection. Then erase what isn’t the spacer.

Make sure to reverse any exposed blue back faces.

I assume this is for 3D printing? Generally I find iteasier to model small stuff like this using meters instead of inches. So for your 1-1/2 in. wide spacer I would model it at 1.5 meters wide. The exported .stl file will be unitless. If you choose inches for the import units when you import it into the slicer, it’ll be the right size.

It worked but it became non-manifold. I assume that’s because I got excited about your solution and didn’t read on about reversing and exposed blue black faces. I’m not actually sure what that means however. Can you elaborate?

Faces in SketchUp have fronts and backs (and zero thickness). In a 3D shape such as your spacer, you should only see white front faces on the outside. In terms of 3D printing, the back faces are toward the printing media and the front faces are toward the air.

After you finished cleaning up the geometry did you create a component or group?

Still cleaning up currently. How much did you have to cleanup to get the final design you posted?

Not much cleaning at all. Just erased the unneeded geometry.