Project Strategy: External Parts, Multiple Parts?

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onekk
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Re: Project Strategy: External Parts, Multiple Parts?

Post by onekk »

dprojects wrote: Sat Feb 04, 2023 10:15 am ...
I agree with some if your considerations.

But:

- You could learn how to do something, even if you have no imaginations.

- You could improve your knowledge.

- You could learn "good habits" and "bad habits"

- You could not learn how to be creative but you could learn some "abstraction techniques" as something that could block your view could be avoided simply making a step on one side, ie changing the point of view and modifying terms of problems.

Man can't fly, but he can build a glider, an aeroplane or even a rocket, but also a parachute or something similar.

Humans have imagination and they could kearn how to use mind to overcome problems, if you have not too much fat in your brain and you have some knowledge of history, art and you read some books.

With some hard work you could even improve your way of thinking, but this is not very easy. :D

Perseverance will help. Repeating schemes and blindly applying rules not too much.

Regards

Carlo D.
GitHub page: https://github.com/onekk/freecad-doc.
- In deep articles on FreeCAD.
- Learning how to model with scripting.
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dprojects
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Re: Project Strategy: External Parts, Multiple Parts?

Post by dprojects »

onekk wrote: Sat Feb 04, 2023 12:25 pm they could kearn how to use mind to overcome problems
Hard work and knowledge is important, even for smart people. Not-smart people can do really a lot if they really work hard.
Studies are mainly learning by heart, a little bit of luck, everyone can graduate if they can learn by heart. No intelligence is needed for this.
If you not smart you can have a very high position in society. There are hundreds of such people in high, respected scientific positions.
My supervisor gave students things he wasn't able to solve, and now they made him a professor ;-) So you don't have to break down right away ;-)

But it is not possible to change anyone to be good planner, engineer, smart person.
If you don't have intelligence, you can only overcome problems from your history, that can be solved in the same way, or exactly the same as described somewhere. But life is not a book ;-)

This is why students with A grade university not must be good worker, problem solver. This is very known corporate issue. They employ best students but they produce poor results, not always of course best student must be poor worker but this happens often. They memorized books, all the solutions there but at work they come across problems that are different, they have to use brain but they don't know how to do it ;-)

It's a bit sad because no one chooses how they will be born.

Thanks
Darek
github.com/dprojects

workbench for woodworking is available at: github.com/dprojects/Woodworking
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onekk
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Re: Project Strategy: External Parts, Multiple Parts?

Post by onekk »

You are mostly right, but it is not to blame people, probably educational system is not uncommon that advanced nations have a very conventional education system that give most importance to conform to a standard.

Here in Italy we have many creative people that have been poor students.

Sadly most of our politicians were good students, so no creativity at all, at least in solving problems of the majority of the other people. :D

But this is off topic.

Regards

Carlo D.
GitHub page: https://github.com/onekk/freecad-doc.
- In deep articles on FreeCAD.
- Learning how to model with scripting.
- Various other stuffs.

Blog: https://okkmkblog.wordpress.com/
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Re: Project Strategy: External Parts, Multiple Parts?

Post by dprojects »

onekk wrote: Sat Feb 04, 2023 8:02 pm But this is off topic.
People do not choose, who they are. This also applies to appearance. Some people are so ugly looking, for example me, that only the computer wants to be with them ;-)

It's a bit sad. What would the world look like if you could decide everything? There would be an elite of the rich who would produce geniuses, perfect people, and the rest as wood?

This is totally on topic, not off-topic. I would say the exact answer to the question asked. Because the author of this thread is looking for the "holy grail", "a way for everything", "one solution to various problems".

It is possible that God faced such a problem "how to solve any problem", and therefore he invented a man who is so flawed that it is impossible to list all the flaws, but he can approach the problem using his brain and solve any problem. No robot or computer that executes commands will do this, and although it has much more computing power and memory capacity than a human. But the computer is not human and does not think. Even artificial intelligence will not work like a human. Man will always "lead" artificial intelligence ;-)

Thanks
Darek
github.com/dprojects

workbench for woodworking is available at: github.com/dprojects/Woodworking
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Re: Project Strategy: External Parts, Multiple Parts?

Post by ppemawm »

ChipsNChips wrote: Sat Feb 04, 2023 5:05 am Now I want to model my first part that will fit that existing object. So I start a new file for that part. Can I see the model of the existing object while modeling my part in this new file? This would help me to work to both the dimensions and the shape of the existing object.
If you are going to be working with assemblies then I suggest you pick an assembly workbench and learn how to use it. I prefer Assembly4 which may be the easiest to learn once you grasp the concept.

My general workflow using The Assembly4 and PartDesign workbenches is as follows:

1. Create an Assembly4 file, Model, and Body(s) in the Parts folder which includes a default LCS in each Body for assembly.
2. Double left click the Body which takes you to PartDesign to create first sketch.
3. Locate first sketch on an mating interface which automatically locates the LCS for the body for assembly. Create features.
3.1 Add LCS's and/or Hole Axes at each additional assembly interface as you model. Attach these to the sketch that creates the assembly interface.
4. All bodies are located at the global origin while modelling. If drawings are not available I assemble the body before creating any features.
5. Assembling the body allows you to work in-context which I prefer, i.e. top down. Select the body link not the original body in the Parts folder.
6. I tend to put all bodies for a sub-assembly in one Assembly4 file since it is easier to manage and distribute the files for larger projects.
6.1 You can still re-use these bodies in other projects but the sub-assembly file has to be open. Or, you can save them to their own file for re-use.
6.2 If there are many purchased parts or .step files I usually put all those in one file in an Assembly4 part container for each.
7. All parts that must be able to move should be in the same sub-assembly which makes it easier (possible) to animate the model to check clearances, etc.
7.1 E.g. sub-assemblies for stationary, rotating, and reciprocating or articulating bodies.
8. I usually assemble the sub-assemblies in the top assembly as I create them in the same sequence as you might assemble them on the bench.

Another top-down approach can be found here: viewtopic.php?p=586394#p586394 and also here for something somewhat simpler viewtopic.php?t=48473.
"It is a poor workman who blames his tools..." ;)
ChipsNChips
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Re: Project Strategy: External Parts, Multiple Parts?

Post by ChipsNChips »

From some of the replies it looks like I opened a bucket of worms. This one seems to be on point but I certainly don't understand it very well at this point. I am going to print it so I can have it at hand and refer to it as I work.

I have seen enough of CAD and 3D CAD programs to know that FreeCAD is a very complex tool and it can be used many ways. I doubt that I will live long enough to understand all of it, even if I use it 12 hours a day, 7 days a week, and 52.xx weeks a year until then. My strategy is to jump in (the deep end?) and start making models. And ask questions when I feel I need to. Oh, and I was a C student in college. Barely graduated. But I never let that stop me when I want to do something. I just jump in .....

Thanks!

And thanks for all the answers.


ppemawm wrote: Sun Feb 05, 2023 1:25 am
ChipsNChips wrote: Sat Feb 04, 2023 5:05 am Now I want to model my first part that will fit that existing object. So I start a new file for that part. Can I see the model of the existing object while modeling my part in this new file? This would help me to work to both the dimensions and the shape of the existing object.
If you are going to be working with assemblies then I suggest you pick an assembly workbench and learn how to use it. I prefer Assembly4 which may be the easiest to learn once you grasp the concept.

My general workflow using The Assembly4 and PartDesign workbenches is as follows:

1. Create an Assembly4 file, Model, and Body(s) in the Parts folder which includes a default LCS in each Body for assembly.
2. Double left click the Body which takes you to PartDesign to create first sketch.
3. Locate first sketch on an mating interface which automatically locates the LCS for the body for assembly. Create features.
3.1 Add LCS's and/or Hole Axes at each additional assembly interface as you model. Attach these to the sketch that creates the assembly interface.
4. All bodies are located at the global origin while modelling. If drawings are not available I assemble the body before creating any features.
5. Assembling the body allows you to work in-context which I prefer, i.e. top down. Select the body link not the original body in the Parts folder.
6. I tend to put all bodies for a sub-assembly in one Assembly4 file since it is easier to manage and distribute the files for larger projects.
6.1 You can still re-use these bodies in other projects but the sub-assembly file has to be open. Or, you can save them to their own file for re-use.
6.2 If there are many purchased parts or .step files I usually put all those in one file in an Assembly4 part container for each.
7. All parts that must be able to move should be in the same sub-assembly which makes it easier (possible) to animate the model to check clearances, etc.
7.1 E.g. sub-assemblies for stationary, rotating, and reciprocating or articulating bodies.
8. I usually assemble the sub-assemblies in the top assembly as I create them in the same sequence as you might assemble them on the bench.

Another top-down approach can be found here: viewtopic.php?p=586394#p586394 and also here for something somewhat simpler viewtopic.php?t=48473.
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dprojects
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Re: Project Strategy: External Parts, Multiple Parts?

Post by dprojects »

If this is so important for you to see the model at once, maybe it is better to build the general model using simple Cubes.
Next go into details and only at the end start dividing it into files and possibly further development.
This is the strategy I use. The model composed of simple not connected blocks at the beginning gives more possibilities for later expansion.

It all depends on what is most important to you, there is no one modeling strategy that is right for all cases.

Thanks
Darek
github.com/dprojects

workbench for woodworking is available at: github.com/dprojects/Woodworking
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