I was not aware of the practices which differentiate a professional CAD Designer from a beginner CAD Designer.Until I started Designing professionally.There are certain essential rules that beginner never follows. Or ignore as they sometimes become monotonous.
Read my post… What will make you a Great Design Engineer?
Welcome to The World Of CAD Software.
Every CAD designer needs to understand how a CAD modeling software works. The 3D models that you see on your screen are nothing but set of Differential equations that define the model you are building.
Now every time you add a feature or make an operation to your model the software performs the complex calculations.Even the small operations you perform like, rotation, transformation and resize of your model require a lot of calculations at the backend.
Now even when your 3D Model looks perfect to you, there are high chances that it might not be.
Which of course, will cause a lot of problems while modeling at a later stage. Most of the beginner don’t find any problem, as they could not judge the fault.
What do you need to do to become a professional CAD designer?
NO, you don’t need to learn programming to be a software friendly designer.
Yes, but you need to change some of your habits and start modeling in a much professional way.
WHAT ARE SOME OF THE MISTAKE BEGINNERS PERFORMS
1. Under-Constrained Sketches | Professional CAD designer
Under – constrained sketches are one of the most common mistakes which every beginner does. Sometimes because drawing doesn’t have the dimension or sometimes they are too lazy to do so.
It’s a blunder!!!
It’s like asking your 3D modeling software to solve those complex differential equations without providing the input values. And then you expecting a perfect 3D model as a solution.
If dimensions are not given in the drawing, give appropriate dimensions.
Never leave it under constrained.
2. Over-Constrained Sketches | Professional CAD designer
Sometimes while making a profile, the software automatically assume the geometrical constraints (such as parallel, perpendicular, tangent).
Avoid or use the automatic constraints with extra caution.
It is both helpful and irritating at times. You may end up giving having undesirable geometrical constraints to you model which are very difficult to find later. The modern software indicates you in the case of an over-constrained sketch.
3. Use geometrical constraints where ever possible | Professional CAD designer
Let’s do a Case study:
Suppose you need A Point at the mid of a 10-inch long line. There are two methods. We will analysis how both the method affect our design.
A.Using dimensional constraints.
Take a point in direction of line. Exactly 5 inches away from one of the extreme point.
B. Using geometric constraint
Take a point on the line and give it mid point constraint.(geometrical constraint). Well both the method perform the same action. Where is the difference?
Now suppose that you need to change the dimension of the line from 10-inches to 15-inch.
In the first case, the point is no longer at the centre while the geometrically constrained point will remain at the centre of the line.
A geometrically constrained sketch is easy to control than a dimensionally constrained sketch.
4. POSITIVE, NEGATIVE, DRESS UP Approach | Professional CAD designer
A better way to build your model is to first add the volume to you sketches. (Using Pad/Extrude, Revolve/Shaft, Multi-section, Sweep/Rib.)
Then removing the extra material for hole or cavity. (Grove or hole command)
And only after the model is complete you should perform dress up features like round, fillet, chamfer and other.
Add > Remove > Dress-up
5. Draft you model to know your mistakes | Professional CAD designer
I personally found this very useful. I was making lots of minor mistakes, which I never realised I did. It helps you read the drawing better and let you know if your approach is correct or not.
What you need to do is keep drafting the model in a separate tab as you progress with you model. You can compare the drawing of the 3D model you are creating with the 2D drawing you have.
6. Naming them for future reference | Professional CAD designer
If you are working on a complex model. You will end up creating miles long specification tree. Any modifications will take hours to find the right feature in the tree.
Name the important feature as you create the model.
CATIA: you can make a separate geometrical set to help you fragments your tasks in different geometrical sets.
7. Save the file correctly | Professional CAD designer
It not only benefits you but also the person who will rework on you models.
The best way to save you cad file is:
Step 1: Click the Fit In All Button. (it will set the model in centre of the screen)
Step 2: Set the model in Isometric View (It gives the better view of a 3D model)
Step 3: Select the model view type as Shade with Edges (for large part or assembly you can set it to wire frame mode. It will help the model load faster, when someone opens it)
CAUTION: Save all the components of an assembly in the same folder and avoid renaming the file or the folder directly.