×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Top down or Skeleton

Top down or Skeleton

Top down or Skeleton

(OP)
Got a new project to create a parametric assembly. 200 or so parts with some sub-assemblies. Question is, top-down.....or the skeleton approach. Any suggestions? I've done some top down in the past but have only played a little with the skeleton approach.

Jason

SolidWorks 2007 SP3.1 on WinXP SP2

RE: Top down or Skeleton

Hello Jason,

I like top down, but keep in mind it works best for "one of a kind parts in a one of a kind assembly".

If this is not the case you can still use top down, but disable external references.

You can also use equations and have some variables control the critical dimensions.

Yes you can do the skeleton sketch approach, I find it good for weldments.

And finally if your assembly is "configurable" you can use DriveWorksXpress.

cheers,

RE: Top down or Skeleton

IMO, if you are using subassy's, better to do bottom up.

Chris
SolidWorks 07 3.0/PDMWorks 07
AutoCAD 06
ctopher's home (updated 04-21-07)

RE: Top down or Skeleton

I've been working with modular products for the past several years.  What I find best is to have a controlling Sketch (skeleton) that the sub-assemblies are constrained to in a Bottom-up approach.

One particular product line has ~50 configurations, ~15 sub-assemblies and ~700 total parts.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read FAQ731-376: Eng-Tips.com Forum Policies to make the best use of Eng-Tips Forums?

RE: Top down or Skeleton

I do a lot of my work top down.  First thing I do is create layout sketches in my assembly and then build my geometry referencing the layout sketches as much as possible.  I try to keep any reference to other geometry in my assembly to a minimum.  I also base my mating on the layout sketches and planes.

I do this for two main reasons.  First, when I need to change the design down the road I only have to to go the layout sketches and make adjustments.  This keeps things simplier and less confusing.  Second, when changes are made my over all assembly has a higher probability of success (less chance of issues) because it's referencing the layout sketches not the surrounding geometry.  If you use a lot of split lines you'll immediately see the benefits of referencing the layout sketches.

Rob Rodriguez CSWP
www.axiscadsolutions.com
www.robrodriguez.com
http://designsmarter.typepad.com/rob_rodriguez/
Eastern Region SWUGN Representative www.swugn.org  www.nvtswug.com
SW 2007 SP 2.0

RE: Top down or Skeleton

Quote:

Question is, top-down.....or the skeleton approach
I'm confused! The "skeleton approach" is a major tool for creating Top Down designs. How are you differentiating the two?

Yes, skeletons can be used with Bottom Up parts to create hybrid in-context parts (which is my preference), but are they not effectively Top Down type constraints?

cheers

RE: Top down or Skeleton

(OP)
I have to have the sub-assys. And parts in the sub-assys need to be driven by other parts in other sub assys....or all from the top level.

By skeleton I mean a master part file with sketches, planes, axis, etc that is inserted into the component parts. Its likea  backwards top down....no assembly required....at least you don't drive it from an assy.

Driveworks xpress may eventually come into play here....but for the current project, I need to just create a parametric sizable assy with parts.

Jason

SolidWorks 2007 SP3.1 on WinXP SP2

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources