Hi Michael,

you wrote: "Use window selection (where you click in an empty area and then hold down and drag to make a selection rectangle) to select the inner piece in the boolean difference command, since it is not easy to click on it since it is contained within the main piece."

Unfortunately I was not able to select the inner piece using window select (covering the entire object with the selection window).

Could you please explain more detailled how to select the inner piece?

thanks & regards
Jurgen

Hi Jurgen,

> Could you please explain more detailled how to select the inner piece?

Please check out these previous posts for some animations and additional descriptions:
http://moi3d.com/forum/index.php?webtag=MOI&msg=1810.2
http://moi3d.com/forum/index.php?webtag=MOI&msg=3324.4

But basically the 2 main things are that you'll want to do the window select starting on the left and dragging towards the right (the left-to-right direction will make a selection box that will only select things entirely inside the box), and normally to do a window select you need to do the initial mouse down in an empty area of the screen - if there is no empty area easily available then hold down both the shift + ctrl keys before clicking which will force a window selection and avoid doing an object drag which is what would normally happen when you click and drag the mouse on top of an object.

- Michael

Hi Michael,

Thank you for the detailled explanation.

I was now able to select the inner piece and perform the boolean difference.
Unfortunately the result of my first try was not a 'clean' Shell.

But the result of my second try (with the original Solid) was a 'clean' Shell, after:
1. Separating the Solid obtaining 10 Surfaces
2. Joining the 3 Surfaces obtaining Surface A
3. Joining the other 7 Surfaces obtaining Surface B
4. Joining the Surfaces A an B obtaing a/the Solid
5. Offsetting (as you suggested)
6. Boolean Differencing (as you suggested)

Thank you very much again
Jurgen

a little image of the result will be cool :)

Hi Michael,

I completely agree with you.

My original solid was built the way you suggest, using Boolian operations to cut this solid out of a cube.

Only after running into problems with Shell and/or Fillet I was 'crying' for help.

But now my problem has been solved by following your explanations/suggestions: I was able to produce a 'clean' shell.

Thanks & regards
Jurgen

p.s. your 'realtime' replies are 'breathtaking'.
The next time I will probably get an answer before I hit "Post" ;-)
Thank you again for the excellent support you provide!!

Hi Jurgen, you're welcome, and I'm glad you have a solution now!

- Michael

Hi Pilou,

Please find attached the picture of the object discussed (rouge) and a picture of another object (white).
The white object is a 3D-printed Shell.
3D-printing Shells instead of solids saves material/money.

I am currently in Cannes.
If you are interested we could meet and exchange ideas/experiences.

regards/Jurgen

cool sculpture :)
Cannes movie festival is alas closed ;)

Hi Jurgen,

Have you done any work with modeling in support structure, like ribs, so you can produce large pieces?

Chris

Hi Chris,

The short answer is: no, I have not yet.

The longer answer/explanation is:
I send my STL-files to Shapeways (http://www.shapeways.com) for 3D-printing in PA 2200 (see http://www.shapeways.com/materials/white_strong_flexible).
The maximum size is 70x58x38 cm.
But I have not produced large pieces, as even at $1.50/cm3 it's getting expensive quickly...
For large pieces (up to 1m3) I use currently a hotwire EPS cutting machine.
But I am now trying to design a re-usable mould with MOI to be printed in PA2200, with which I would then like to produce multiple copies of an object.
For this mould I will probably have to build a support structure...

I hope this info is of some use to you
regards/Jurgen

Jurgen,

I can imagine ways that rods, dowels or tubing could be used for large pieces. It would be useful to know if there is a reliable method to model in a support structure (using the printing material itself) that is cost effective.

You must have created some holes in your shape so the unused material could be emptied?

Chris