20 comments

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  Ocell

  10 months ago

  I'm looking forward to the post, I wish I could read it now, you've got me all fired up for it!
  
  Toasters are always fun design exercises. (No really, I'm being serious) A few nice parting lines in the shell, plenty of sliding/lever relationships for parts, and all driven by the dimensions of a slice of bread!
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  Josh M

  10 months ago

  Dang, good one! That is cool to think about. interesting what shapes control design.
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  Dale Dunn

  10 months ago

  In order to showcase the strengths of top-down parametric design, there should be configurations for different sizes and quantities of toast.
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  lukeseed

  10 months ago

  Top down may make things faster when designing but becomes a nightmare once in production.
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  Kyle Mason

  10 months ago

  I'm thinking of some great big funky wine-rack. Don't ask me where that came from.
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  Ivan

  10 months ago

  hmmm... you could do something mechanical with assembly motion, moving parts... engine, scissor lift, adjustable conveyors
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  Marijn

  10 months ago

  I made a bbq in my middle technical school and I still use it, it is rusty like hell. But it is pure craftmanship the bbq works always and the rust wont get true the metal!
  So design a DIY (do it yourself) bbq!
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  Bradley Grzesiak

  10 months ago

  Stapler! =) I kid, I kid.
  
  I always finish up with bottom-up assemblies, but sometimes I'll start with top-down designs. If I need a bunch of parts and subassemblies to fit into a small space, top-down is the way to go. But once that design is perfected, I convert it to bottom-up. When dealing with configuration management and ECR/ECNs, the last thing you want is one part to auto-update another.
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  JeffMirisola

  10 months ago

  Do you remember "Weird Science"...?
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  Marijn

  10 months ago

  haha I prefere bottoms-up when you go there :)
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  Charles Culp

  10 months ago

  I model with a mouse in my right hand and my left on the keyboard shortcuts.
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  Daniel

  10 months ago

  Hi Josh,
  
  How about an assembly that shows the dangers of leaving in context relations, ie circular relations, broken relations, too many relations, etc.?
  
  Daniel
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  Catch 22

  10 months ago

  Hi Josh-
  
  Bottom Up is my preference. Why? Because In Context External References don't belong in our universe. Ever Checked In a Part file with these References into an electronic vault? A worm hole opens up and you're transported to the 4th dimension.
  
  Devon
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  John

  10 months ago

  My first choice would be something with Weldments since that's about 90% of what I do. Thanks for all of your informative posts - I really love this site!
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  jeff b

  10 months ago

  i began my life as a confident slightly self-centered Top-Downer, but i have sense been converted to a Bottom-Upper. Current job uses a vault and parts get handed around more then baby in need of a diaper change. now maybe 10% of the time when i'm doing a presentation and the parts are all mine, i'll do a combination.
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  Chris Booth

  10 months ago

  I agree with Ivan, who suggests "something mechanical with assembly motion, moving parts... engine, scissor lift, adjustable conveyors". For me, top-down design comes into its own when you really NEED to use it, when you couldn't even imagine the shape a part should be unless you see the rest of the assembly going through its planned motion.
  
  For example: If you go to the Wolfram Demonstrations Project ( http://demonstrations.wolfram.com/ ) and search for "Hoberman" you'll find some examples of mechanisms where the design of one part is very much dependent on the design of other parts, and also the overall results of motion for the mechanism as a whole are difficult to forsee without constantly simulating the motion during the design process.
  
  Here's the sort of thing you could do with these mechanisms: Watch the web preview of the "Ring of Hoberman Rings" example. Can't you just see how you're really looking down on a new type of connected parasols for sun terraces suspended overhead that does away with those annoying poles that either get in your way as you walk around or else go right through your table?
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  Brad Moon

  10 months ago

  I also agree with Ivan, who suggests, "something mechanical with assembly motion, moving parts... engine, scissor lift, adjustable conveyors". Adjustable conveyors preferred.
  
  That said, I would like to know more about the pitfalls of TDD that Jeff B refers to.
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  Josh M

  10 months ago

  You all have had great suggstions. I'm considering some scenarios to show
  and will definitely go over the 'pitfalls', the do's and don't's of top-down
  and bottom-up. Thanks for letting me know what you're interested in seeing.
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  john

  8 months ago

  hi, (sorry for my english)
  with the top down method:
  if a part references another one then the part is fixed and i cant mate it.
  im a new user.is there a way to avoid this ?
  thnx
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  Josh M

  8 months ago

  John, hi. yes, this is one thing you need to watch with top-down design. I recommend that all parts that reference other parts be fixed. If it's not, then if the unfixed part moves, th references will stay and change the shape (intent) of the part.
  
  However, keeping parts unfixed can be used while conceptualizing to test out different ideas.
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