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Top-down Design usuing surfaces


New member
When I start most of my designs I genrally do not know what I am designing and so I usually build a skeleton model first. This model usually consists of just datum features but, I have just started to use surfaces in an attempt to avoid having to reproduce features and hopefully speed things up. What are the consequences of this, in terms of modelling difficulty, regeneration speed and other issues I havn't thought of?

Any thoughts would be appreciated.



New member
No difficulity that I know of. Use Copy Geom to get a mating surface to work from works fine and guarantees a fit. Its not so easy to forget a matching detail that way that way. This is a basic top down design approach and is highly recommended.



New member
This design approach is called the Master Model technique, and is the best way to create a robust model. Changes in your skeleton(or map) part pass down to the part and subassembly level automatically. Whith any approach, there are compromises, but Master Model is the best for cases where multiple objects need to relate to eachother in an assembly.


New member
I have to agree with jperkins and ProFishent. Don't worry about regen time, as surfaces are usually not time-killers. I use surfaces extensively in large assembly modeling. Like jperkins said, it helps maintain assembly relationships and it also helps avoid interferences in tight spaces.