Round bottom indentation help


#1

I am new to SketchUp and have learned a lot the past couple of days. My project that initially took me 4 hours to do I can now do from scratch in about 1 hour. I am trying to make a series of round indentations around a circular path. I laid out the pattern of circles and was trying to figure out how to “dish” them out. The mating surface on the next part will have the same pattern with raised circles to match.

Any ideas? And thank you!


#2

Maybe like this?

For something simple like the above, you can use Offset on the inside of the circles to create the boundary for the bottom of the dimple. Then, either select the large surface or the inner circles, get the Move tool and invoke Autofold with Alt on the PC or Command on the Mac and move the selection the required distance.


#3

Very close to what’s in my head! If they were completely dished so a ball would fit in. Similar to a marble game board. Wanting to be able to cut it with a ball mill.


#4

That would require a different approach. Draw the ball and distribute it around the surface. Use Intersect Faces to intersect the balls with the surface. Then erase the part of the balls that extend above the surface leaving the rounded dimples.


#5

I have been trying to use an arc to rotate on a center point to dish it out but have not had any success.


#6

I really appreciate your help. Like I mentioned I am very new and cannot even figure out how to make a ball. I assume once it is made the portion can be subtracted from the item?


#7

You can make a sphere by drawing two concentric circles…only on different axes. Draw one flat on the ground plane, centred on the origin. Then draw another vertically…also centred on the origin. Select the horizontal one as a path then just click the vertical one with the Follow Me tool. It will spin on its axis to form a sphere.


#8

Yeah. That’s not a great approach.

You can use a couple of circles at 90 degrees to each other and Follow Me to create the ball.


Position the first ball, intersect it with the surface, delete the top part of the ball and the face skinning the dimple. Also correct any reversed faces.


Then use Rotate/Copy to make copies of the dimple.


#9

Thats exactly what I am trying to do! Now for me to spend the next couple of hours trying to replicate it! Again THANKS!


#10

Hi, I’ve been trying to replicate your work. A student wants to 3D print something like a BB8. She needs to make a largeish “dimple” in a sphere. I’ve followed the above and put a sphere on/into another sphere. Then I’ve chosen “Intersect Faces” and selected “with model”. But then I’m stuck. I’ve tried the erase tool. I’ve tried to backspace to delete but it either deletes everything or nothing. I’ve tried making a bowl and then putting the bowl into a larger sphere, done the intersecting faces but still can’ manage to erase the bowl leaving the “dimple” behind. I must be missing something simple but don’t know what.
Thanks!!!
David


#11

Is either the sphere, the dimple a component or group? In order to get the dimple into the sphere, all of the geometry needs to be in the same context. That is, either none of it grouped or all of it in the same group. If you can upload your model as you’ve got it, it’ll be easier to help you sort it out.

In general, when I need to do something like this, I would make a component of the sphere, draw the dimple and move it where I need it to be on the sphere. Since the dimple geometry would be outside of the sphere component, the dimple can’t modify the sphere. When I’m ready to modify the sphere, I would select the dimple geometry and cut it to the clipboard. Then I would open the sphere component for editing and use Paste in place to put the dimple geometry in place. Select all of the geometry, right click and choose Intersect Faces>With Selection and erase the unneeded geometry.


I used keyboard shortcuts some of the operations.

Select the sphere for the dimple.
Cut to clipboard.
Open sphere component for editing.
Paste in place.
Select all.
Intersect Faces>With Selection.
Select the unneeded part of the dimple sphere and delete it.
Select the skin over the dimple and delete it.
Correct the reversed faces in the dimple.


#12

Thank you for taking the time to help me with this!!! I’ll try that when I have that computer again tomorrow.
David


#13

I reckon this could be done with follow me as well.

Shep


#14

Thats not a moon, it’s a space station.

When will this deathstar be fully operational?


#15

Beautiful!!! Thank you all. I worked at it this morning, following your excellent directions again and again so carefully and it just wasn’t working!!! Tried different things, no go. Frustration! Then I read your notes yet again and finally saw paste IN PLACE. I didn’t know of that command and has just figured it meant that I needed to paste it where I wanted it.
YAY! Thank you! Thank you! She will be able to make her BB8! (now figuring out how to attach the little sphere to the bigger sphere will be the next hurdle…but I think she/we can figure out something that won’t be too complicated that will at least let the little ball move back and forth).
You all are terrific!
David


#16

Very good!

FWIW, I use Paste in place so much that I have set up a keyboard shortcut for it. I use it more than regular old Paste, in fact.

The reason I did this the way I showed it with the small sphere outside the larger component is so that the small one can be moved around without risking its geometry merging with the geometry of the large sphere. It’s sort of like using a pencil to mark out where you want to cut something before you commit to cutting it.

She might also find it worthwhile to learn about the Dave Method.


#17

Nice! I noticed a difficulty in working with very small items. this is a good way to get around that. Thanks.


#18

I too want do have a spherical indentation in something I 3D print so I have been busy intersecting spheres and solids. At first the spheres worked perfectly using the circle-line-circle-follow-me technique, but now I have an issue…
The first few times I tried the follow-me method, it worked perfectly. Now for some reason, following the process as closely as I can recall, I get holes in my sphere. When drawing my initial circle (100 sides) at the origin, 20mm radius, then drawing the line from the origin, down the green axis and then drawing another circle, also 100 sides and 20mm radius, my resultant sphere has holes where the green axis passes through it. Some numbers of sides seems to produce the holes, but 24 sides does not – and I’d really like my surface to be smoother than 24 sides.
Is the follow-me technique restricted to spheres constructed of circles of less than 29 sides? (28 has no holes, 29 does).


#19

See the post two above yours mentioning the Dave method.


#20

While you were responding (and thanks), I was discovering the fact that holes-in-a-sphere effect seems to be a scaling problem. I can make perfect spheres 200mm radius with 50 sides and then scale them by .1, .1, .1 and get exactly what I want. Strange that the 24 sided circle seems immune to the hole but 30 is not. Takeaway: There is more than one way to skin a cat in SketchUp. Case closed.