You have better time to remake your surface in a solid! ;)

As you put the little solid inside the big no matter if the internal curve of the little solid is not absolutly like your first one ;)
Now the boolean Union will works like a charm!



And the fillet a game's boy ;)


Of course I take only one rail from your model, just retake any number you want ;) 2 is the maximum for the rails except the possible third scaling rail ;)
Else you must make your Sweep by parts and merge all at the end!

Hi Franz, thanks for posting the example.

So actually in that case there even though you've got an open surface object and not both solid volumes, since the open surface is sticking all the way through the solid and making a well defined closed intersection curve with it, it is actually supposed to be ok to use in a boolean union like that. But there is a bug in boolean union that is preventing it from working 100% properly, I think it's something that I can fix up for the next v3 beta release.

In the meantime, the boolean union will actually make all the pieces you need, you will just need to manually discard one piece and then join the other pieces together to glue things into a solid.

Here are the steps - select both the objects in your moulinex2.3dm that you posted above, then run Construct > Boolean > Union.

This will calculate a result but it will be fragmented into some pieces. There is one piece that you need to delete manually. To do that select this piece here:



You actually want to keep that piece, but it's in the way so you will need to hide it to more easily get at the actual piece you need to delete which is underneath it.

So push Edit > Hide - that will hide that selected object (if you push Edit > Hide with something selected, if you push it with nothing selected it shows all the hidden objects). So after hiding it you will see this:



That's not actually one single object, it's 2 different objects in separate pieces - select this one here:



And then delete that one. You will see a result like this:




Now show that piece that was hidden earlier, and now you have the proper 2 pieces to make up your solid - select the 2 pieces and use Edit > Join and they will be glued together into a solid.

The bug is that boolean union is supposed to automatically delete pieces like that which are forming a sort of "interior cell wall" between 2 solid regions. But the code that is doing that is getting confused by the "seam edge" of the closed surface and not recognizing it as being a piece fully bounded by all non-manifold edges. Once I fix the bug and take seam edges into account the union calculation should then get the proper result and automatically remove that interior piece as part of the boolean and you won't need to do any extra steps here.

Thanks for posting the file, sometimes the reason why things don't work as expected is because it's a bug that needs to be fixed and it really helps to have the example to work with to find out what's going on!

It is however not necessarily a bad idea to form solids for each piece that you are using to do the booleans - when each part is a solid you know it's a closed object and the booleans will be a little more bulletproof as far as giving you the expected results when the pieces involved are all solids initially.

- Michael

Ciao,
I have built a real solid starting from a closed U profile and now it works fine :)
I continue with other parts, thank you very much.
Franz

Hello, I made some proofs with some holes + fillets. I saw that I have to use a different tecnique depending on the case. If one fails the other one works. See the image.
Ciao, Franz

Hi Franz,

> I saw that I have to use a different tecnique depending on the case. If one fails the other one works. See the image.

Really either method should work, just as long as you have constructed a result that does fully intersect the other object.

If you want some more feedback on the ones that don't work, could you please post a 3DM file with the objects in them so I can test over here and see what's going on?

One tip - it can be easiest to make sure your cutting object extends a bit past just the outer surface of the object to be cut, that way you can be sure that it actually fully divides the object where it cuts into it.

- Michael

Hi Michael,
I will try to replicate the issues then I will upload the file. Thank you very much.
Franz

Hi everybody !

I'm currently learning Moi and am stucked with the 8th step of this tutorial : the inward extrusion.
I've tried with the Extrude and Shell tools but it goes wrong everytime.
After a lot of tries, I have to admit that I'm rather lost and would like to have this step a bit more detailed..

Could someone please help me?
I've attached my 3dm file.


Thank's !

Like this ?

Hi,

No, I talk about the step before. My bad. I can't get the thickness of the body.:

"Here I Extruded the edge shape inward a little to get depth, I used a line to guide the direction of the extrude to 45 degrees where needed.
You can also shrink all of the port shapes (copies of them) inward and perform a Loft between the edge curves and the copy.
Join these new walls to the body. Try to Fillet them to get a nice "punched-in" contour."

http://moi3d.com/forum/get_attachment.php?webtag=MOI&hash=c16cad76a239d19240c369df9a670679&filename=mix_015_08_extrude-join-fillet.jpg



I'm not sure if I didn't understand what he means or if I did understand but it doen't work because i did something wrong before..

Thank's for your help !

Ah sorry like this ?
Maybe not the same than in the tutorial but result will be the same! :)

Hi Loganka,

> I'm not sure if I didn't understand what he means or if I did understand but it
> doen't work because i did something wrong before..

So I think that step means to select the edges around your hole, like for example make a selection like this on your model that you posted:



Then run the Construct > Extrude command, which will punch out those edges into a surface along one straight direction. By default the direction will be along a world x, y, or z axis direction like this:


That will work fine for your top one but for the side ones where you want it to go along a 45 degree angle, you will need to push the "Set dir" option in Extrude:



Once you push "Set dir" in Extrude, that then asks you to pick 2 points and the extrusion direction will go on the line between those 2 points. So to get the extrusion to go at a 45 degree angle you would want to switch to the Front view, pick the first point at the origin snap and the second point anywhere along a 45 degree angle line from the origin. You can use angle constraint to get an exact 45 degree angle by typing in <45 and push enter right before you pick the second point. That will enable a one shot angle constraint of 45 degrees so that straight snap will go in 45 degree increments for that one pick rather than the regular default 90 degrees. Or if you are going to be doing a lot of 45 degree angle things, you can change the default straight snap to 45 degrees under Options> Snaps > Straight snap options > Snap angle.

Once you pick the 2 points you will then be back in the extrude distance stage and you can enter in a distance or pick a point with the mouse and your mouse will track along that newly defined direction line.

Once you have built an extrusion in this way you then select the extrusion and the main body and use Edit > join to glue them togeher.

Hope this helps!

- Michael

Hi,

I'm new to MoI and 3D too, so I tried to do this exercise.

I think the problem is after the extruding operation: for an outside fillet one must boolean/union the two or more faces where the fillet is to come. That means that after selecting the model you need to click again on the body to select the face and then click on the extruded faces, do a boolean union and only after this you can fillet.

The fillet itself is very small (1mm at the most).

I find the filleting in MoI not very intuitive..

Hope this helps.


Frank

Hi Frank - yes after building things in this way as individual separate surfaces that are next to each other you then usually want to join the surfaces together so that they have a shared joined edge between them rather than being totally separate objects.

Although you can use Boolean union to do that, I'd generally recommend to use the Edit > Join command instead for this type of combining (when combining along shared edges). That's because the booleans are more focused on trying to intersect objects and potentially remove material from them, so they will go through some extra calculations to try and determine if the objects being unioned need to be cut up. The Edit > Join command on the other hand is only focused on gluing edges together and does not attempt to do any intersection or cutting step at all.

And yes for doing the regular edge-based filleting that's done on joined edges so you want to get the pieces joined together after you have built surfaces.

When possible it can be nice to keep things as solids more throughout the entire process and carve pieces away using boolean operations rather than building individual surfaces. That can then avoid needing to join things together as a separate step since they stay joined throughout. But it can also be helpful to work at the individual surface level for building more complex models as well, that's why MoI supports either way.

When you work at a surface level you will end up doing some more manual joining steps.

- Michael

Hi Michael,

After some experimenting I ended up joining two joined surfaces and then the fillet was OK.

I tried the solid/boolean thing and that worked OK too.

Thanks,

Frank