I keep having sub-assemblies fail in the parent assembly. If I open the sub-assembly, it's fine. If I edit it in the parent, I can usually get it to resolve / rebuild OK. It's making it difficult to create a parent with flexible sub-assemblies when the children keep failing. Is there some option to make everything rebuild all the way down?
Yeah, what Mark said. Also sometimes making the subassembly rigid and then flexible again will fix it.
SolidWorks just can't resolve sub-components correctly. In the assembly, I have a rod with threaded ends - extrude circle, 1.5" long cosmetic thread on each end. I pull up the assembly and it's threaded the full length. Open the part and it shows threaded the full length, until I edit the cosmetic thread. Then SW remembers it's only supposed to thread 1.5" and shows it correctly. The whole assembly keeps behaving this way.
So... your problem is about cosmetic threads, not how mates solve in a final assembly that has flexible subs? You wasted my time. Done with this thread.
Sorry Mark. That was just the first example that showed itself this morning. I appreciate your input.
Sucks trying to answer a vague question. Flexible sub assembly problems are very different than cosmetic thread problems. Flexible subs can be hard to control, but have important use, and I view cosmetic thread issues as rather insignificant. Cosmetic threads are flakey at best. I have issues with them in part models, assembly models, and sometimes drawings, that I tend to ignore.
I really didn't want to post to this question the first time, since there was not much specific to go on, but I was trying to respond with something other than 'post your model and spefic issues'.
The assembly is a linkage, or perhaps a series of linkages. So there's a lot of this pin in that hole going on. In some cases, it's a pin in a hole in this sub-assembly mating to a bushing in a hole in another sub-assembly. Then that goes in another assembly and the everything gets repeated for the loose ends.
I went back through the assemblies this morning. I figured it was just too many concentric constraints for SolidWorks to keep track of. So I tried to redo the mates so that instead of mating the pin in hole A in sub-assembly A to the bushing in hole B in sub-assembly B I just mated hole A to hole B. Doing that a few times seemed to get it working.
I meant to ask earlier, what is the difference between the ctrl-q rebuild and a ctrl-b rebuild?
CTRL-Q
Force rebuilt of top level ASM's
CTRL-B
Rebuilt of new/changed items
Thank you Peter.
Can you post a screenshot to help explain? Can you pattern any of the sub assemblies, so you don't need to mate them all?
Mark,
See below. Rather than mating the pins in the clevises to the bushings in the bars, I mated the holes in the clevises to the holes in the bars. Note there's still something that attaches to the empty hole and there's a clevis on the other end of each rod so the whole thing makes other stuff move in the assembly.
So what sub assemblies are you setting to flexible? The rod and clevis assemblies look like they would stay at a fixed length, so they would not need to be a flexible sub assembly? Just wondering if you're setting sub assemblies to flexible when they do not need to be.
The other question to ask is, why do they need to move in the SW model? Are you creating an animation or checking how things move in a new design? If you are just creating a drawing for shop assembly, I would not worry about having the assembly function as in real life, just set it to how the shop floor needs to understand the drawing and assemble the product.
This is a component and is set to flexible in its parent, as are the other subs that mate to this in the parent. And yes, I'm checking function.
Bill,
A component can't be set to flexible, only sub-assemblies.
Paul
Assuming Bill means the rods and bracket are an assembly, and set to flexible in the parent assembly.
When I can't get flexible subs to work, I dissolve them (into their components) in the parent assembly, and just mate them normally. Throw a sledgehammer at the problem kind of attack, but ends the frustration.
Mark,
You assume correctly. I'd maintain that a component could be a part or an assembly, but I understand what Paul means. I almost did dissolve everything, but I need to keep the structure the way it's going to be in production. I don't really feel like creating one assembly to test it and another to release it.
Flexible subs are a bit tricky since the mates in the sub solve in the parent assembly. It's possible you could have circular or over defining mates between the sub and parent. Sometimes a ctrl-q rebuild will fix things, sometimes two ctrl-q rebuilds in a row will fix then break it. When I use flexible sub assemblies, I try to leave as few degrees of freedom open in the sub. Don't do them too often.