Series of articles about the pitfalls of parametric editing
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Series of articles about the pitfalls of parametric editing
I just came upon this series of articles about the inherent fragility of parametric modeling, I think it's an interesting read.
It is from Evan Yares, the same blogger (a CAD industry long timer) who wrote the "CAD usability sucks" series last year. He sure seems to like controversial titles!
Rather than discard parametrics altogether in favor of a direct modeling approach, he suggests a new modeling strategy which can be applied to most parametric CAD packages. He does not give much info about it though, I don't know if the guy who came up with it plans to monetize it somehow. I was able to get a PDF of his presentation at Solid Edge University, but I haven't read it yet.
The failed promise of parametric CAD part 1: From the beginning
The failed promise of parametric CAD part 2: The problem is editing
The failed promise of parametric CAD part 3: The direct solution
The failed promise of parametric CAD part 4: Going horizontal
The failed promise of parametric CAD part 5: A resilient modeling strategy
A Resilient Modeling Strategy - Solid Edge University
It is from Evan Yares, the same blogger (a CAD industry long timer) who wrote the "CAD usability sucks" series last year. He sure seems to like controversial titles!
Rather than discard parametrics altogether in favor of a direct modeling approach, he suggests a new modeling strategy which can be applied to most parametric CAD packages. He does not give much info about it though, I don't know if the guy who came up with it plans to monetize it somehow. I was able to get a PDF of his presentation at Solid Edge University, but I haven't read it yet.
The failed promise of parametric CAD part 1: From the beginning
The failed promise of parametric CAD part 2: The problem is editing
The failed promise of parametric CAD part 3: The direct solution
The failed promise of parametric CAD part 4: Going horizontal
The failed promise of parametric CAD part 5: A resilient modeling strategy
A Resilient Modeling Strategy - Solid Edge University
- sliptonic
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Re: Series of articles about the pitfalls of parametric editing
Interesting read indeed. Is the pdf one you can share?
Re: Series of articles about the pitfalls of parametric editing
The pdf is already linked, it's the last one.
Re: Series of articles about the pitfalls of parametric editing
Very good approach. It shows clearly that parametric has its pitfalls. My company too has a model schema guide.
I think when FreeCAD is more mature it makes sense to define one too.
I think when FreeCAD is more mature it makes sense to define one too.
Stop whining - start coding!
- sliptonic
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- Joined: Tue Oct 25, 2011 10:46 pm
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Re: Series of articles about the pitfalls of parametric editing
Doh!normandc wrote:The pdf is already linked, it's the last one.
Re: Series of articles about the pitfalls of parametric edit
I just found that there is now a video. It's mostly the same content as the PDF, but it's interesting that early on, it shows an example of bad modeling, then how to model it in a more robust manner.
http://resilientmodeling.com/V3_RMS_Groups_Video.html
Edit 2015/01/20: the website was changed, there is not a single video anymore but a series of them. You can browse the site here: http://resilientmodeling.com
If you are wondering like I was what an ECO stands for, it's Engineering Change Order.
Some of the advice cannot be applied to FreeCAD at the moment, but maybe with the PartDesign Body merged to master that will change.
http://resilientmodeling.com/V3_RMS_Groups_Video.html
Edit 2015/01/20: the website was changed, there is not a single video anymore but a series of them. You can browse the site here: http://resilientmodeling.com
If you are wondering like I was what an ECO stands for, it's Engineering Change Order.
Some of the advice cannot be applied to FreeCAD at the moment, but maybe with the PartDesign Body merged to master that will change.
Last edited by NormandC on Wed Jan 21, 2015 2:45 am, edited 1 time in total.
Reason: Fixed link, they changed the website layout...
Reason: Fixed link, they changed the website layout...
Re: Series of articles about the pitfalls of parametric edit
Hi,
I tried to replicate the demo modell (what is showed in the video), but I stuck.
Is there anyone succeed?
I know it is a general concept and I'm trying to copy a specific example,
but still would be nice to replicate the almost same project tree as shown on the presentation.
Update:
I stuck at the "Tombstone 12mm wide" step.
Here is where I'm: Update2:
Ok.
Tombstone: check:)
Obligatory pic: Now I stuck at the "Replace face" feature. Cant find it.
I'm pretty sure it is the "removeSplitter()" python function:
For those who want to proceed, here is the 3D model:
I tried to replicate the demo modell (what is showed in the video), but I stuck.
Is there anyone succeed?
I know it is a general concept and I'm trying to copy a specific example,
but still would be nice to replicate the almost same project tree as shown on the presentation.
Update:
I stuck at the "Tombstone 12mm wide" step.
Here is where I'm: Update2:
Ok.
Tombstone: check:)
Obligatory pic: Now I stuck at the "Replace face" feature. Cant find it.
I'm pretty sure it is the "removeSplitter()" python function:
Code: Select all
head_thread = head.fuse(shaft_unthreaded).removeSplitter()
Last edited by arcol on Sat Feb 01, 2014 3:57 pm, edited 1 time in total.
Re: Series of articles about the pitfalls of parametric edit
Update3:
(sorry only 3 attachment/post allowed).
This is where I'm: This is what I can't do: Any idea? Maybe the loft feature?
Ok, I gave up. If anyone wants to continue, play with, I uploaded the latest model I have. Have fun!
(sorry only 3 attachment/post allowed).
This is where I'm: This is what I can't do: Any idea? Maybe the loft feature?
Ok, I gave up. If anyone wants to continue, play with, I uploaded the latest model I have. Have fun!
Re: Series of articles about the pitfalls of parametric edit
Hi arcol!
It's hard to replicate the video without "Body" container. Unfortunately the "Body" is not implemented in the master FreeCAD so far, only in the "assembly" branch. In your file cylinders and rest of model aren't connected with each other. You do boolean fusion and them add a pad on cylinder planar face.
PS I dissagre with some statements from the video, as size in feature name, "3.99" radius thing and especially "replace face" - what kind of sorcery is this?
It's hard to replicate the video without "Body" container. Unfortunately the "Body" is not implemented in the master FreeCAD so far, only in the "assembly" branch. In your file cylinders and rest of model aren't connected with each other. You do boolean fusion and them add a pad on cylinder planar face.
PS I dissagre with some statements from the video, as size in feature name, "3.99" radius thing and especially "replace face" - what kind of sorcery is this?
Re: Series of articles about the pitfalls of parametric edit
No it isn't. removeSplitter() is the algorithm behind the "Part --> Refine shape" menu tool. When doing boolean operations, the OCC kernel leaves residual edges. removeSplitter() cleans those edges by joining coplanar faces.arcol wrote:Now I stuck at the "Replace face" feature. Cant find it.
I'm pretty sure it is the "removeSplitter()" python function:
The video shows a work flow specific to Solid Edge. The author of the Resilient Modeling Strategy is a Solid Edge reseller. The method appears sound and may be useful in FreeCAD, but as jriegel said, we will have to customize it to FreeCAD's workflow.
FreeCAD currently does not have a tool similar to Solid Edge's Replace face tool.
"Replace face" is a very useful tool that I've used quite a few times. I certainly hope that something similar gets added to FreeCAD in the future. But it may require some complex coding!kwahoo wrote:especially "replace face" - what kind of sorcery is this?
I for one can't wait for jriegel to merge the assembly branch into the master branch. it will be "soon"... (but the assembly itself will be disabled as it's not fully usable at the moment and will see considerable changes)kwahoo wrote: It's hard to replicate the video without "Body" container. Unfortunately the "Body" is not implemented in the master FreeCAD so far, only in the "assembly" branch.
Right now and for the past few months I've refrained from posting any elaborate video tutorials, knowing that with the Body container and working planes, the Part Design work flow will drastically change. All of the current FreeCAD videos focusing on Part Design found on YouTube will basically be obsolete.