Sub-assemblies sucks

Hi, I have a rather simple assembly with 16 parts, 5 of them are axles which are parallel to each other.

I wonder if anybody could share his thoughts on my experience with assemblies and mates - especially when those assemblies include sub-assemblies.

Here goes my experience:

A. When creating sub-assemblies within assemblies, there are occasions where solidworks stuck sub-assemblies and parts, although they have still one way of freedom. this happens with no error message: the sub-assembly is just fixed in place while attempting free drag (there are no InPlace mates and no FIX condition. they are also not fully-defined). Sometimes two or more parts in a sub assembly which are not fully defined between them appear in the major assembly as a bunch of parts which are "frozen" or glued together although there are degrees of freedom between them, and they move only as a whole assembly together.

B. If I reconstruct the assembly which appears in paragraph A, as a simple assembly with no sub-assemblies (one "layer" hierarchy), then everything works fine and as expected - peculiar isn't it!

This is the second time this happens me on an assembly with sub-assemblies, and it forces me to abandon completely the sub-assemblies on my assemblies - this really sucks when projects starts to be complicated and in relation to BOM in drawings and who knows what else!

BTW, I use SW2006 SP4.1

Gil

Unless I'm misunderstanding your needs, there's flexible subassemblies, and although they have their issues sometimes, they've been improved in

With these you can still move individual parts of a sub assembly in a top level assembly.

All you need to do is leave some degrees of freedom in your sub assembly free, and designate the sub assembly as flexible in the upper assembly. (Right click the sub assembly in the feature manager, Component Properties, Solve as, flexible.

Good luck.

--Matt Schroeder

You can move parts of a subassembly within an assembly. You need to go to the component properties dialog box and change "Solve As" from "Rigid" to "Flexible".

Nothing surprising here, this is basic functionality. Sounds like a training issue.

Matt, Thanks!!! that's exactly what I wanted! a magic sequence of mouse clicks. I'm so glad I have this newsgroup for all my solidworks questions.

Regards, Gil

Hi Markus, Read the reply Matt posted to my question - it might surprise you, as it helped me a lot!

Regards, Gil

You should feel fortunate...a lot of cad programs don't have this option.

Gil Alsberg wrote:

it has been around since 2001 or 01+. it was improved significantly in

If Matt is correct, as to the point that this functionality was introduced in SW2005, then it is not so obvious as some might think. Regarding the training issue: I guess you are right. (although I still managed to get CSWP certified before a couple of months, without knowing this functionality).

Cheers, Gil

Indeed, I am feeling fortunate!

"Flexible Assemblies", they are neat but use with caution. Overuse will get you (or at least your SolidWorks assembly) into trouble.

Ken

Which ones??

John H

To expand on that..... One of the key benefits to splitting a large assembly into sub-assemblies is it makes it much easier for SWX to solve the mates, as it can solve them for each sub-assy in turn, after which it treats the sub-assys as single entities - this is why the original poster found they were moving as a single block.

If you use the "flexible" option, it effectively has to solve the assembly as if all the components (and hence all their mates) were added to the top level. It therefore gets complicated = slower = sometimes falls over.

So I would say it's an invaluable feature at times, but only use it when you HAVE to.

John H

John, That was a terrific summation of the value of subassemblies in dynamically moving systems (and issues with flexible subassemblies). Nice