Combination of two objects

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koluna
Posts: 285
Joined: Thu Sep 20, 2018 12:36 pm

Combination of two objects

Postby koluna » Wed Aug 05, 2020 5:06 pm

Hi, Dears!

It is a holder for yogurts :)
How can I make a combination of two objects (Top Base and Array)?
Should I use Parts or Part Design?
Help me, please.

OS: Linux Mint 19.3 (MATE/mate)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.
Build type: Release
Branch: unknown
Hash: 6903b4fe6b437c069e24aeabdfd22f524f815e15
Python version: 3.6.9
Qt version: 5.9.5
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/UnitedStates (en_US)
Attachments
snezok.FCStd
(34.63 KiB) Downloaded 24 times
2.png
2.png (79.04 KiB) Viewed 690 times
openBrain
Posts: 4507
Joined: Fri Nov 09, 2018 5:38 pm

Re: Combination of two objects

Postby openBrain » Wed Aug 05, 2020 5:29 pm

Use Part, definitely.
  • Set 'Fuse' property of array to 'True'
  • Select both objects (array & top plate) and Part->Split->Boolean Fragments
  • On the obtained object : Part->Compound->Explode Compound
  • Delete the unwanted fragments
  • Optionally delete the fragments Group, without deleting the inner fragments
  • Select all the remaining fragments and Part->Boolean->Union
Final result attached.
Attachments
snezok_OB.FCStd
(74.62 KiB) Downloaded 22 times
koluna
Posts: 285
Joined: Thu Sep 20, 2018 12:36 pm

Re: Combination of two objects

Postby koluna » Thu Aug 06, 2020 10:35 am

openBrain wrote:
Wed Aug 05, 2020 5:29 pm
  • Set 'Fuse' property of array to 'True'
From specification:

Code: Select all

if it is True, and the copies intersect with each other, they will be fused together into a single shape.
Is it realy needed?

Thanks a lot! :)
I did it. But, why is it so hard?
openBrain
Posts: 4507
Joined: Fri Nov 09, 2018 5:38 pm

Re: Combination of two objects

Postby openBrain » Thu Aug 06, 2020 11:46 am

koluna wrote:
Thu Aug 06, 2020 10:35 am

Code: Select all

if it is True, and the copies intersect with each other, they will be fused together into a single shape.
Is it realy needed?
Yes. You can experience strange behaviors with Compound that are not fused when their different shapes intersect.
I did it. But, why is it so hard?
I guess the object you're modeling is actually not so trivial. ;)
HK sxx
Posts: 57
Joined: Mon Apr 20, 2020 5:32 pm

Re: Combination of two objects

Postby HK sxx » Thu Aug 06, 2020 4:15 pm

koluna wrote:
Wed Aug 05, 2020 5:06 pm

Should I use Parts or Part Design?
Help me, please.
Hello,

You can also use Part Design. It is not very difficult and you can make it parametric:

1> you make the first bowl: create body --> sketch - Revolution --> Thickness
2> You make three clones of the previous body: and place them in position with Placement. Now you have 4 bodies.
3> you make the flap: create body --> sketch - Pad --> sketch - Pocket --> Fillet; and place them in position with Placement. Now you have 5 bodies
4> You make a boolean fusion with 5 bodies.

I had issues in step 4, with boolean merge. I couldn´t make it with PartDesign, so finally I make it with Part Workbench.

With a little more effort it can be made fully parametric.

To see if you like it, I attach the file.

Sorry for my English. I hope it is understood.

Regards.
yogurtera.png
yogurtera.png (176.43 KiB) Viewed 590 times
Attachments
yogurtera.FCStd
(51.48 KiB) Downloaded 21 times
openBrain
Posts: 4507
Joined: Fri Nov 09, 2018 5:38 pm

Re: Combination of two objects

Postby openBrain » Thu Aug 06, 2020 5:15 pm

HK sxx wrote:
Thu Aug 06, 2020 4:15 pm
You can also use Part Design. It is not very difficult and you can make it parametric:
How about a much simpler solution ? Only 3 operations and full parametric.
Diameter of slots and material thickness are respectively DatumLine X and Z position.
All other parameters are in sketch 'Sketch'. ;)
Yogourt_OB.png
Yogourt_OB.png (63.55 KiB) Viewed 575 times
Attachments
Yogourt_OB.FCStd
(31.02 KiB) Downloaded 28 times
HK sxx
Posts: 57
Joined: Mon Apr 20, 2020 5:32 pm

Re: Combination of two objects

Postby HK sxx » Thu Aug 06, 2020 6:17 pm

openBrain wrote:
Thu Aug 06, 2020 5:15 pm
HK sxx wrote:
Thu Aug 06, 2020 4:15 pm
You can also use Part Design. It is not very difficult and you can make it parametric:
How about a much simpler solution ? Only 3 operations and full parametric.
Diameter of slots and material thickness are respectively DatumLine X and Z position.
All other parameters are in sketch 'Sketch'. ;)
Yogourt_OB.png
Yes, a much better, simpler and cleaner solution.

Thank you.
koluna
Posts: 285
Joined: Thu Sep 20, 2018 12:36 pm

Re: Combination of two objects

Postby koluna » Thu Aug 13, 2020 7:08 am

HK sxx wrote:
Thu Aug 06, 2020 4:15 pm
Sorry for my English. I hope it is understood.
Thanks a lot! :)
openBrain wrote:
Thu Aug 06, 2020 5:15 pm
How about a much simpler solution ?
Well, well, well... You are very clever superman :)
Explain me your way, please :)
I will try to make this.
Thanks a lot!!! :)
jmaustpc
Posts: 9991
Joined: Tue Jul 26, 2011 6:28 am
Location: Australia

Re: Combination of two objects

Postby jmaustpc » Thu Aug 13, 2020 8:29 am

Some questions
if this is a yogurt container then it would not have a hole in the bottom of the cup, is this really a pot for growing a plant which would need the drain hole in the bottom?

If this is a yogurt container then the volume of the cup would be critical as the yogurt would be sold by volume or weight. If by volume then you should calculate the volume in the spreadsheet so that when the dimensions are changed you can directly see the change to the volume. If sold by weight then you would do the same as volume, but with an extra calculation with the "specific gravity" or "unit weight" or "density" of the yogurt.

If this is for yogurt then the volume would be critical so you should define the cups by their internal volume/dimensions, according to Google translate you don't seem to have defined it that way.

Is the wall thickness of the cup and its base thickness always the same or do they need to be separately specified? I assume that the thickness of the top plate would be separately defined as it is quite likely thinner so that the cups can be snapped off.

How do you want to define the centre distances of the top of the cups? If you want this to be as parametric as possible then I would have thought you would define the centre distances via a calculation using the distance between the top of each cup so that the top plate would always have enough material no matter what size you decided to make the top of the cups.

I have to go for a few hours now, I might have an attempt at this later. I would have thought that you could model the whole thing in one PartDesign Body and with FreeCAD 0.19 use a multi-pattern feature after modelling the first cup.

Jim
openBrain
Posts: 4507
Joined: Fri Nov 09, 2018 5:38 pm

Re: Combination of two objects

Postby openBrain » Thu Aug 13, 2020 9:14 am

koluna wrote:
Thu Aug 13, 2020 7:08 am
Well, well, well... You are very clever superman :)
Explain me your way, please :)
I will try to make this.
Thanks a lot!!! :)
Actually that's not so easy to explain it without knowing where you can have difficulty to understand and which detail level is needed. I think the good way is that you analyze the file by turning on each feature from the start to the end of the model, and tell where it's unclear for you. ;)